Branch data Line data Source code
1 : : /*-------------------------------------------------------------------------
2 : : *
3 : : * nbtreadpage.c
4 : : * Leaf page reading for btree index scans.
5 : : *
6 : : * NOTES
7 : : * This file contains code to return items that satisfy the scan's
8 : : * search-type scan keys within caller-supplied btree leaf page.
9 : : *
10 : : * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group
11 : : * Portions Copyright (c) 1994, Regents of the University of California
12 : : *
13 : : * IDENTIFICATION
14 : : * src/backend/access/nbtree/nbtreadpage.c
15 : : *
16 : : *-------------------------------------------------------------------------
17 : : */
18 : :
19 : : #include "postgres.h"
20 : :
21 : : #include "access/nbtree.h"
22 : : #include "access/relscan.h"
23 : : #include "storage/predicate.h"
24 : : #include "utils/datum.h"
25 : : #include "utils/rel.h"
26 : :
27 : :
28 : : /*
29 : : * _bt_readpage state used across _bt_checkkeys calls for a page
30 : : */
31 : : typedef struct BTReadPageState
32 : : {
33 : : /* Input parameters, set by _bt_readpage for _bt_checkkeys */
34 : : ScanDirection dir; /* current scan direction */
35 : : OffsetNumber minoff; /* Lowest non-pivot tuple's offset */
36 : : OffsetNumber maxoff; /* Highest non-pivot tuple's offset */
37 : : IndexTuple finaltup; /* Needed by scans with array keys */
38 : : Page page; /* Page being read */
39 : : bool firstpage; /* page is first for primitive scan? */
40 : : bool forcenonrequired; /* treat all keys as nonrequired? */
41 : : int startikey; /* start comparisons from this scan key */
42 : :
43 : : /* Per-tuple input parameters, set by _bt_readpage for _bt_checkkeys */
44 : : OffsetNumber offnum; /* current tuple's page offset number */
45 : :
46 : : /* Output parameters, set by _bt_checkkeys for _bt_readpage */
47 : : OffsetNumber skip; /* Array keys "look ahead" skip offnum */
48 : : bool continuescan; /* Terminate ongoing (primitive) index scan? */
49 : :
50 : : /*
51 : : * Private _bt_checkkeys state used to manage "look ahead" optimization
52 : : * and primscan scheduling (only used during scans with array keys)
53 : : */
54 : : int16 rechecks;
55 : : int16 targetdistance;
56 : : int16 nskipadvances;
57 : :
58 : : } BTReadPageState;
59 : :
60 : :
61 : : static void _bt_set_startikey(IndexScanDesc scan, BTReadPageState *pstate);
62 : : static bool _bt_scanbehind_checkkeys(IndexScanDesc scan, ScanDirection dir,
63 : : IndexTuple finaltup);
64 : : static bool _bt_oppodir_checkkeys(IndexScanDesc scan, ScanDirection dir,
65 : : IndexTuple finaltup);
66 : : static void _bt_saveitem(BTScanOpaque so, int itemIndex,
67 : : OffsetNumber offnum, IndexTuple itup);
68 : : static int _bt_setuppostingitems(BTScanOpaque so, int itemIndex,
69 : : OffsetNumber offnum, const ItemPointerData *heapTid,
70 : : IndexTuple itup);
71 : : static inline void _bt_savepostingitem(BTScanOpaque so, int itemIndex,
72 : : OffsetNumber offnum,
73 : : ItemPointer heapTid, int tupleOffset);
74 : : static bool _bt_checkkeys(IndexScanDesc scan, BTReadPageState *pstate, bool arrayKeys,
75 : : IndexTuple tuple, int tupnatts);
76 : : static bool _bt_check_compare(IndexScanDesc scan, ScanDirection dir,
77 : : IndexTuple tuple, int tupnatts, TupleDesc tupdesc,
78 : : bool advancenonrequired, bool forcenonrequired,
79 : : bool *continuescan, int *ikey);
80 : : static bool _bt_check_rowcompare(ScanKey header,
81 : : IndexTuple tuple, int tupnatts, TupleDesc tupdesc,
82 : : ScanDirection dir, bool forcenonrequired, bool *continuescan);
83 : : static bool _bt_rowcompare_cmpresult(ScanKey subkey, int cmpresult);
84 : : static bool _bt_tuple_before_array_skeys(IndexScanDesc scan, ScanDirection dir,
85 : : IndexTuple tuple, TupleDesc tupdesc, int tupnatts,
86 : : bool readpagetup, int sktrig, bool *scanBehind);
87 : : static void _bt_checkkeys_look_ahead(IndexScanDesc scan, BTReadPageState *pstate,
88 : : int tupnatts, TupleDesc tupdesc);
89 : : static bool _bt_advance_array_keys(IndexScanDesc scan, BTReadPageState *pstate,
90 : : IndexTuple tuple, int tupnatts, TupleDesc tupdesc,
91 : : int sktrig, bool sktrig_required);
92 : : static bool _bt_advance_array_keys_increment(IndexScanDesc scan, ScanDirection dir,
93 : : bool *skip_array_set);
94 : : static bool _bt_array_increment(Relation rel, ScanKey skey, BTArrayKeyInfo *array);
95 : : static bool _bt_array_decrement(Relation rel, ScanKey skey, BTArrayKeyInfo *array);
96 : : static void _bt_array_set_low_or_high(Relation rel, ScanKey skey,
97 : : BTArrayKeyInfo *array, bool low_not_high);
98 : : static void _bt_skiparray_set_element(Relation rel, ScanKey skey, BTArrayKeyInfo *array,
99 : : int32 set_elem_result, Datum tupdatum, bool tupnull);
100 : : static void _bt_skiparray_set_isnull(Relation rel, ScanKey skey, BTArrayKeyInfo *array);
101 : : static inline int32 _bt_compare_array_skey(FmgrInfo *orderproc,
102 : : Datum tupdatum, bool tupnull,
103 : : Datum arrdatum, ScanKey cur);
104 : : static void _bt_binsrch_skiparray_skey(bool cur_elem_trig, ScanDirection dir,
105 : : Datum tupdatum, bool tupnull,
106 : : BTArrayKeyInfo *array, ScanKey cur,
107 : : int32 *set_elem_result);
108 : : #ifdef USE_ASSERT_CHECKING
109 : : static bool _bt_verify_keys_with_arraykeys(IndexScanDesc scan);
110 : : #endif
111 : :
112 : :
113 : : /*
114 : : * _bt_readpage() -- Load data from current index page into so->currPos
115 : : *
116 : : * Caller must have pinned and read-locked so->currPos.buf; the buffer's state
117 : : * is not changed here. Also, currPos.moreLeft and moreRight must be valid;
118 : : * they are updated as appropriate. All other fields of so->currPos are
119 : : * initialized from scratch here.
120 : : *
121 : : * We scan the current page starting at offnum and moving in the indicated
122 : : * direction. All items matching the scan keys are loaded into currPos.items.
123 : : * moreLeft or moreRight (as appropriate) is cleared if _bt_checkkeys reports
124 : : * that there can be no more matching tuples in the current scan direction
125 : : * (could just be for the current primitive index scan when scan has arrays).
126 : : *
127 : : * In the case of a parallel scan, caller must have called _bt_parallel_seize
128 : : * prior to calling this function; this function will invoke
129 : : * _bt_parallel_release before returning.
130 : : *
131 : : * Returns true if any matching items found on the page, false if none.
132 : : */
133 : : bool
134 : 10230682 : _bt_readpage(IndexScanDesc scan, ScanDirection dir, OffsetNumber offnum,
135 : : bool firstpage)
136 : : {
137 : 10230682 : Relation rel = scan->indexRelation;
138 : 10230682 : BTScanOpaque so = (BTScanOpaque) scan->opaque;
139 : : Page page;
140 : : BTPageOpaque opaque;
141 : : OffsetNumber minoff;
142 : : OffsetNumber maxoff;
143 : : BTReadPageState pstate;
144 : : bool arrayKeys,
145 : 10230682 : ignore_killed_tuples = scan->ignore_killed_tuples;
146 : : int itemIndex,
147 : : indnatts;
148 : :
149 : : /* save the page/buffer block number, along with its sibling links */
150 : 10230682 : page = BufferGetPage(so->currPos.buf);
151 : 10230682 : opaque = BTPageGetOpaque(page);
152 : 10230682 : so->currPos.currPage = BufferGetBlockNumber(so->currPos.buf);
153 : 10230682 : so->currPos.prevPage = opaque->btpo_prev;
154 : 10230682 : so->currPos.nextPage = opaque->btpo_next;
155 : : /* delay setting so->currPos.lsn until _bt_drop_lock_and_maybe_pin */
156 : 10230682 : pstate.dir = so->currPos.dir = dir;
157 : 10230682 : so->currPos.nextTupleOffset = 0;
158 : :
159 : : /* either moreRight or moreLeft should be set now (may be unset later) */
160 : : Assert(ScanDirectionIsForward(dir) ? so->currPos.moreRight :
161 : : so->currPos.moreLeft);
162 : : Assert(!P_IGNORE(opaque));
163 : : Assert(BTScanPosIsPinned(so->currPos));
164 : : Assert(!so->needPrimScan);
165 : :
166 : : /* initialize local variables */
167 : 10230682 : indnatts = IndexRelationGetNumberOfAttributes(rel);
168 : 10230682 : arrayKeys = so->numArrayKeys != 0;
169 [ + + ]: 10230682 : minoff = P_FIRSTDATAKEY(opaque);
170 : 10230682 : maxoff = PageGetMaxOffsetNumber(page);
171 : :
172 : : /* initialize page-level state that we'll pass to _bt_checkkeys */
173 : 10230682 : pstate.minoff = minoff;
174 : 10230682 : pstate.maxoff = maxoff;
175 : 10230682 : pstate.finaltup = NULL;
176 : 10230682 : pstate.page = page;
177 : 10230682 : pstate.firstpage = firstpage;
178 : 10230682 : pstate.forcenonrequired = false;
179 : 10230682 : pstate.startikey = 0;
180 : 10230682 : pstate.offnum = InvalidOffsetNumber;
181 : 10230682 : pstate.skip = InvalidOffsetNumber;
182 : 10230682 : pstate.continuescan = true; /* default assumption */
183 : 10230682 : pstate.rechecks = 0;
184 : 10230682 : pstate.targetdistance = 0;
185 : 10230682 : pstate.nskipadvances = 0;
186 : :
187 [ + + ]: 10230682 : if (scan->parallel_scan)
188 : : {
189 : : /* allow next/prev page to be read by other worker without delay */
190 [ + - ]: 890 : if (ScanDirectionIsForward(dir))
191 : 890 : _bt_parallel_release(scan, so->currPos.nextPage,
192 : : so->currPos.currPage);
193 : : else
194 : 0 : _bt_parallel_release(scan, so->currPos.prevPage,
195 : : so->currPos.currPage);
196 : : }
197 : :
198 : 10230682 : PredicateLockPage(rel, so->currPos.currPage, scan->xs_snapshot);
199 : :
200 [ + + ]: 10230682 : if (ScanDirectionIsForward(dir))
201 : : {
202 : : /* SK_SEARCHARRAY forward scans must provide high key up front */
203 [ + + ]: 10195759 : if (arrayKeys)
204 : : {
205 [ + + ]: 70267 : if (!P_RIGHTMOST(opaque))
206 : : {
207 : 22601 : ItemId iid = PageGetItemId(page, P_HIKEY);
208 : :
209 : 22601 : pstate.finaltup = (IndexTuple) PageGetItem(page, iid);
210 : :
211 [ + + ]: 22601 : if (unlikely(so->scanBehind) &&
212 [ + + ]: 1910 : !_bt_scanbehind_checkkeys(scan, dir, pstate.finaltup))
213 : : {
214 : : /* Schedule another primitive index scan after all */
215 : 276 : so->currPos.moreRight = false;
216 : 276 : so->needPrimScan = true;
217 [ - + ]: 276 : if (scan->parallel_scan)
218 : 0 : _bt_parallel_primscan_schedule(scan,
219 : : so->currPos.currPage);
220 : 276 : return false;
221 : : }
222 : : }
223 : :
224 : 69991 : so->scanBehind = so->oppositeDirCheck = false; /* reset */
225 : : }
226 : :
227 : : /*
228 : : * Consider pstate.startikey optimization once the ongoing primitive
229 : : * index scan has already read at least one page
230 : : */
231 [ + + + + ]: 10195483 : if (!pstate.firstpage && minoff < maxoff)
232 : 22498 : _bt_set_startikey(scan, &pstate);
233 : :
234 : : /* load items[] in ascending order */
235 : 10195483 : itemIndex = 0;
236 : :
237 : 10195483 : offnum = Max(offnum, minoff);
238 : :
239 [ + + ]: 38733349 : while (offnum <= maxoff)
240 : : {
241 : 36485606 : ItemId iid = PageGetItemId(page, offnum);
242 : : IndexTuple itup;
243 : : bool passes_quals;
244 : :
245 : : /*
246 : : * If the scan specifies not to return killed tuples, then we
247 : : * treat a killed tuple as not passing the qual
248 : : */
249 [ + + + + ]: 36485606 : if (ignore_killed_tuples && ItemIdIsDead(iid))
250 : : {
251 : 2155479 : offnum = OffsetNumberNext(offnum);
252 : 2155479 : continue;
253 : : }
254 : :
255 : 34330127 : itup = (IndexTuple) PageGetItem(page, iid);
256 : : Assert(!BTreeTupleIsPivot(itup));
257 : :
258 : 34330127 : pstate.offnum = offnum;
259 : 34330127 : passes_quals = _bt_checkkeys(scan, &pstate, arrayKeys,
260 : : itup, indnatts);
261 : :
262 : : /*
263 : : * Check if we need to skip ahead to a later tuple (only possible
264 : : * when the scan uses array keys)
265 : : */
266 [ + + + + : 34330127 : if (arrayKeys && OffsetNumberIsValid(pstate.skip))
+ - + + ]
267 : : {
268 : : Assert(!passes_quals && pstate.continuescan);
269 : : Assert(offnum < pstate.skip);
270 : : Assert(!pstate.forcenonrequired);
271 : :
272 : 18679 : offnum = pstate.skip;
273 : 18679 : pstate.skip = InvalidOffsetNumber;
274 : 18679 : continue;
275 : : }
276 : :
277 [ + + ]: 34311448 : if (passes_quals)
278 : : {
279 : : /* tuple passes all scan key conditions */
280 [ + + ]: 25939208 : if (!BTreeTupleIsPosting(itup))
281 : : {
282 : : /* Remember it */
283 : 25616321 : _bt_saveitem(so, itemIndex, offnum, itup);
284 : 25616321 : itemIndex++;
285 : : }
286 : : else
287 : : {
288 : : int tupleOffset;
289 : :
290 : : /* Set up posting list state (and remember first TID) */
291 : : tupleOffset =
292 : 322887 : _bt_setuppostingitems(so, itemIndex, offnum,
293 : 322887 : BTreeTupleGetPostingN(itup, 0),
294 : : itup);
295 : 322887 : itemIndex++;
296 : :
297 : : /* Remember all later TIDs (must be at least one) */
298 [ + + ]: 1953162 : for (int i = 1; i < BTreeTupleGetNPosting(itup); i++)
299 : : {
300 : 1630275 : _bt_savepostingitem(so, itemIndex, offnum,
301 : : BTreeTupleGetPostingN(itup, i),
302 : : tupleOffset);
303 : 1630275 : itemIndex++;
304 : : }
305 : : }
306 : : }
307 : : /* When !continuescan, there can't be any more matches, so stop */
308 [ + + ]: 34311448 : if (!pstate.continuescan)
309 : 7947740 : break;
310 : :
311 : 26363708 : offnum = OffsetNumberNext(offnum);
312 : : }
313 : :
314 : : /*
315 : : * We don't need to visit page to the right when the high key
316 : : * indicates that no more matches will be found there.
317 : : *
318 : : * Checking the high key like this works out more often than you might
319 : : * think. Leaf page splits pick a split point between the two most
320 : : * dissimilar tuples (this is weighed against the need to evenly share
321 : : * free space). Leaf pages with high key attribute values that can
322 : : * only appear on non-pivot tuples on the right sibling page are
323 : : * common.
324 : : */
325 [ + + + + : 10195483 : if (pstate.continuescan && !so->scanBehind && !P_RIGHTMOST(opaque))
+ + ]
326 : : {
327 : 74846 : ItemId iid = PageGetItemId(page, P_HIKEY);
328 : 74846 : IndexTuple itup = (IndexTuple) PageGetItem(page, iid);
329 : : int truncatt;
330 : :
331 : : /* Reset arrays, per _bt_set_startikey contract */
332 [ + + ]: 74846 : if (pstate.forcenonrequired)
333 : 1627 : _bt_start_array_keys(scan, dir);
334 : 74846 : pstate.forcenonrequired = false;
335 : 74846 : pstate.startikey = 0; /* _bt_set_startikey ignores P_HIKEY */
336 : :
337 [ + - ]: 74846 : truncatt = BTreeTupleGetNAtts(itup, rel);
338 : 74846 : _bt_checkkeys(scan, &pstate, arrayKeys, itup, truncatt);
339 : : }
340 : :
341 [ + + ]: 10195483 : if (!pstate.continuescan)
342 : 7986247 : so->currPos.moreRight = false;
343 : :
344 : : Assert(itemIndex <= MaxTIDsPerBTreePage);
345 : 10195483 : so->currPos.firstItem = 0;
346 : 10195483 : so->currPos.lastItem = itemIndex - 1;
347 : 10195483 : so->currPos.itemIndex = 0;
348 : : }
349 : : else
350 : : {
351 : : /* SK_SEARCHARRAY backward scans must provide final tuple up front */
352 [ + + ]: 34923 : if (arrayKeys)
353 : : {
354 [ + - + + ]: 52 : if (minoff <= maxoff && !P_LEFTMOST(opaque))
355 : : {
356 : 40 : ItemId iid = PageGetItemId(page, minoff);
357 : :
358 : 40 : pstate.finaltup = (IndexTuple) PageGetItem(page, iid);
359 : :
360 [ + + ]: 40 : if (unlikely(so->scanBehind) &&
361 [ + + ]: 8 : !_bt_scanbehind_checkkeys(scan, dir, pstate.finaltup))
362 : : {
363 : : /* Schedule another primitive index scan after all */
364 : 4 : so->currPos.moreLeft = false;
365 : 4 : so->needPrimScan = true;
366 [ - + ]: 4 : if (scan->parallel_scan)
367 : 0 : _bt_parallel_primscan_schedule(scan,
368 : : so->currPos.currPage);
369 : 4 : return false;
370 : : }
371 : : }
372 : :
373 : 48 : so->scanBehind = so->oppositeDirCheck = false; /* reset */
374 : : }
375 : :
376 : : /*
377 : : * Consider pstate.startikey optimization once the ongoing primitive
378 : : * index scan has already read at least one page
379 : : */
380 [ + + + - ]: 34919 : if (!pstate.firstpage && minoff < maxoff)
381 : 64 : _bt_set_startikey(scan, &pstate);
382 : :
383 : : /* load items[] in descending order */
384 : 34919 : itemIndex = MaxTIDsPerBTreePage;
385 : :
386 : 34919 : offnum = Min(offnum, maxoff);
387 : :
388 [ + + ]: 5638953 : while (offnum >= minoff)
389 : : {
390 : 5604134 : ItemId iid = PageGetItemId(page, offnum);
391 : : IndexTuple itup;
392 : : bool tuple_alive;
393 : : bool passes_quals;
394 : :
395 : : /*
396 : : * If the scan specifies not to return killed tuples, then we
397 : : * treat a killed tuple as not passing the qual. Most of the
398 : : * time, it's a win to not bother examining the tuple's index
399 : : * keys, but just skip to the next tuple (previous, actually,
400 : : * since we're scanning backwards). However, if this is the first
401 : : * tuple on the page, we do check the index keys, to prevent
402 : : * uselessly advancing to the page to the left. This is similar
403 : : * to the high key optimization used by forward scans.
404 : : */
405 [ + + + + ]: 5604134 : if (ignore_killed_tuples && ItemIdIsDead(iid))
406 : : {
407 [ + + ]: 281319 : if (offnum > minoff)
408 : : {
409 : 280848 : offnum = OffsetNumberPrev(offnum);
410 : 280848 : continue;
411 : : }
412 : :
413 : 471 : tuple_alive = false;
414 : : }
415 : : else
416 : 5322815 : tuple_alive = true;
417 : :
418 : 5323286 : itup = (IndexTuple) PageGetItem(page, iid);
419 : : Assert(!BTreeTupleIsPivot(itup));
420 : :
421 : 5323286 : pstate.offnum = offnum;
422 [ + + + + : 5323286 : if (arrayKeys && offnum == minoff && pstate.forcenonrequired)
+ + ]
423 : : {
424 : : /* Reset arrays, per _bt_set_startikey contract */
425 : 4 : pstate.forcenonrequired = false;
426 : 4 : pstate.startikey = 0;
427 : 4 : _bt_start_array_keys(scan, dir);
428 : : }
429 : 5323286 : passes_quals = _bt_checkkeys(scan, &pstate, arrayKeys,
430 : : itup, indnatts);
431 : :
432 [ + + + + ]: 5323286 : if (arrayKeys && so->scanBehind)
433 : : {
434 : : /*
435 : : * Done scanning this page, but not done with the current
436 : : * primscan.
437 : : *
438 : : * Note: Forward scans don't check this explicitly, since they
439 : : * prefer to reuse pstate.skip for this instead.
440 : : */
441 : : Assert(!passes_quals && pstate.continuescan);
442 : : Assert(!pstate.forcenonrequired);
443 : :
444 : 12 : break;
445 : : }
446 : :
447 : : /*
448 : : * Check if we need to skip ahead to a later tuple (only possible
449 : : * when the scan uses array keys)
450 : : */
451 [ + + + + : 5323274 : if (arrayKeys && OffsetNumberIsValid(pstate.skip))
+ - + + ]
452 : : {
453 : : Assert(!passes_quals && pstate.continuescan);
454 : : Assert(offnum > pstate.skip);
455 : : Assert(!pstate.forcenonrequired);
456 : :
457 : 24 : offnum = pstate.skip;
458 : 24 : pstate.skip = InvalidOffsetNumber;
459 : 24 : continue;
460 : : }
461 : :
462 [ + + + + ]: 5323250 : if (passes_quals && tuple_alive)
463 : : {
464 : : /* tuple passes all scan key conditions */
465 [ + + ]: 5321455 : if (!BTreeTupleIsPosting(itup))
466 : : {
467 : : /* Remember it */
468 : 5289352 : itemIndex--;
469 : 5289352 : _bt_saveitem(so, itemIndex, offnum, itup);
470 : : }
471 : : else
472 : : {
473 : 32103 : uint16 nitems = BTreeTupleGetNPosting(itup);
474 : : int tupleOffset;
475 : :
476 : : /* Set up posting list state (and remember last TID) */
477 : 32103 : itemIndex--;
478 : : tupleOffset =
479 : 32103 : _bt_setuppostingitems(so, itemIndex, offnum,
480 : 32103 : BTreeTupleGetPostingN(itup, nitems - 1),
481 : : itup);
482 : :
483 : : /* Remember all prior TIDs (must be at least one) */
484 [ + + ]: 102014 : for (int i = nitems - 2; i >= 0; i--)
485 : : {
486 : 69911 : itemIndex--;
487 : 69911 : _bt_savepostingitem(so, itemIndex, offnum,
488 : : BTreeTupleGetPostingN(itup, i),
489 : : tupleOffset);
490 : : }
491 : : }
492 : : }
493 : : /* When !continuescan, there can't be any more matches, so stop */
494 [ + + ]: 5323250 : if (!pstate.continuescan)
495 : 88 : break;
496 : :
497 : 5323162 : offnum = OffsetNumberPrev(offnum);
498 : : }
499 : :
500 : : /*
501 : : * We don't need to visit page to the left when no more matches will
502 : : * be found there
503 : : */
504 [ + + ]: 34919 : if (!pstate.continuescan)
505 : 88 : so->currPos.moreLeft = false;
506 : :
507 : : Assert(itemIndex >= 0);
508 : 34919 : so->currPos.firstItem = itemIndex;
509 : 34919 : so->currPos.lastItem = MaxTIDsPerBTreePage - 1;
510 : 34919 : so->currPos.itemIndex = MaxTIDsPerBTreePage - 1;
511 : : }
512 : :
513 : : /*
514 : : * If _bt_set_startikey told us to temporarily treat the scan's keys as
515 : : * nonrequired (possible only during scans with array keys), there must be
516 : : * no lasting consequences for the scan's array keys. The scan's arrays
517 : : * should now have exactly the same elements as they would have had if the
518 : : * nonrequired behavior had never been used. (In general, a scan's arrays
519 : : * are expected to track its progress through the index's key space.)
520 : : *
521 : : * We are required (by _bt_set_startikey) to call _bt_checkkeys against
522 : : * pstate.finaltup with pstate.forcenonrequired=false to allow the scan's
523 : : * arrays to recover. Assert that that step hasn't been missed.
524 : : */
525 : : Assert(!pstate.forcenonrequired);
526 : :
527 : 10230402 : return (so->currPos.firstItem <= so->currPos.lastItem);
528 : : }
529 : :
530 : : /*
531 : : * _bt_start_array_keys() -- Initialize array keys at start of a scan
532 : : *
533 : : * Set up the cur_elem counters and fill in the first sk_argument value for
534 : : * each array scankey.
535 : : */
536 : : void
537 : 70697 : _bt_start_array_keys(IndexScanDesc scan, ScanDirection dir)
538 : : {
539 : 70697 : Relation rel = scan->indexRelation;
540 : 70697 : BTScanOpaque so = (BTScanOpaque) scan->opaque;
541 : :
542 : : Assert(so->numArrayKeys);
543 : : Assert(so->qual_ok);
544 : :
545 [ + + ]: 142143 : for (int i = 0; i < so->numArrayKeys; i++)
546 : : {
547 : 71446 : BTArrayKeyInfo *array = &so->arrayKeys[i];
548 : 71446 : ScanKey skey = &so->keyData[array->scan_key];
549 : :
550 : : Assert(skey->sk_flags & SK_SEARCHARRAY);
551 : :
552 : 71446 : _bt_array_set_low_or_high(rel, skey, array,
553 : : ScanDirectionIsForward(dir));
554 : : }
555 : 70697 : so->scanBehind = so->oppositeDirCheck = false; /* reset */
556 : 70697 : }
557 : :
558 : : /*
559 : : * Determines an offset to the first scan key (an so->keyData[]-wise offset)
560 : : * that is _not_ guaranteed to be satisfied by every tuple from pstate.page,
561 : : * which is set in pstate.startikey for _bt_checkkeys calls for the page.
562 : : * This allows caller to save cycles on comparisons of a prefix of keys while
563 : : * reading pstate.page.
564 : : *
565 : : * Also determines if later calls to _bt_checkkeys (for pstate.page) should be
566 : : * forced to treat all required scan keys >= pstate.startikey as nonrequired
567 : : * (that is, if they're to be treated as if any SK_BT_REQFWD/SK_BT_REQBKWD
568 : : * markings that were set by preprocessing were not set at all, for the
569 : : * duration of _bt_checkkeys calls prior to the call for pstate.finaltup).
570 : : * This is indicated to caller by setting pstate.forcenonrequired.
571 : : *
572 : : * Call here at the start of reading a leaf page beyond the first one for the
573 : : * primitive index scan. We consider all non-pivot tuples, so it doesn't make
574 : : * sense to call here when only a subset of those tuples can ever be read.
575 : : * This is also a good idea on performance grounds; not calling here when on
576 : : * the first page (first for the current primitive scan) avoids wasting cycles
577 : : * during selective point queries. They typically don't stand to gain as much
578 : : * when we can set pstate.startikey, and are likely to notice the overhead of
579 : : * calling here. (Also, allowing pstate.forcenonrequired to be set on a
580 : : * primscan's first page would mislead _bt_advance_array_keys, which expects
581 : : * pstate.nskipadvances to be representative of every first page's key space.)
582 : : *
583 : : * Caller must call _bt_start_array_keys and reset startikey/forcenonrequired
584 : : * ahead of the finaltup _bt_checkkeys call when we set forcenonrequired=true.
585 : : * This will give _bt_checkkeys the opportunity to call _bt_advance_array_keys
586 : : * with sktrig_required=true, restoring the invariant that the scan's required
587 : : * arrays always track the scan's progress through the index's key space.
588 : : * Caller won't need to do this on the rightmost/leftmost page in the index
589 : : * (where pstate.finaltup isn't ever set), since forcenonrequired will never
590 : : * be set here in the first place.
591 : : */
592 : : static void
593 : 22562 : _bt_set_startikey(IndexScanDesc scan, BTReadPageState *pstate)
594 : : {
595 : 22562 : BTScanOpaque so = (BTScanOpaque) scan->opaque;
596 : 22562 : Relation rel = scan->indexRelation;
597 : 22562 : TupleDesc tupdesc = RelationGetDescr(rel);
598 : : ItemId iid;
599 : : IndexTuple firsttup,
600 : : lasttup;
601 : 22562 : int startikey = 0,
602 : 22562 : arrayidx = 0,
603 : : firstchangingattnum;
604 : 22562 : bool start_past_saop_eq = false;
605 : :
606 : : Assert(!so->scanBehind);
607 : : Assert(pstate->minoff < pstate->maxoff);
608 : : Assert(!pstate->firstpage);
609 : : Assert(pstate->startikey == 0);
610 : : Assert(!so->numArrayKeys || pstate->finaltup ||
611 : : P_RIGHTMOST(BTPageGetOpaque(pstate->page)) ||
612 : : P_LEFTMOST(BTPageGetOpaque(pstate->page)));
613 : :
614 [ + + ]: 22562 : if (so->numberOfKeys == 0)
615 : 8907 : return;
616 : :
617 : : /* minoff is an offset to the lowest non-pivot tuple on the page */
618 : 13655 : iid = PageGetItemId(pstate->page, pstate->minoff);
619 : 13655 : firsttup = (IndexTuple) PageGetItem(pstate->page, iid);
620 : :
621 : : /* maxoff is an offset to the highest non-pivot tuple on the page */
622 : 13655 : iid = PageGetItemId(pstate->page, pstate->maxoff);
623 : 13655 : lasttup = (IndexTuple) PageGetItem(pstate->page, iid);
624 : :
625 : : /* Determine the first attribute whose values change on caller's page */
626 : 13655 : firstchangingattnum = _bt_keep_natts_fast(rel, firsttup, lasttup);
627 : :
628 [ + + ]: 19301 : for (; startikey < so->numberOfKeys; startikey++)
629 : : {
630 : 15722 : ScanKey key = so->keyData + startikey;
631 : : BTArrayKeyInfo *array;
632 : : Datum firstdatum,
633 : : lastdatum;
634 : : bool firstnull,
635 : : lastnull;
636 : : int32 result;
637 : :
638 : : /*
639 : : * Determine if it's safe to set pstate.startikey to an offset to a
640 : : * key that comes after this key, by examining this key
641 : : */
642 [ - + ]: 15722 : if (key->sk_flags & SK_ROW_HEADER)
643 : : {
644 : : /* RowCompare inequality (header key) */
645 : 0 : ScanKey subkey = (ScanKey) DatumGetPointer(key->sk_argument);
646 : 0 : bool satisfied = false;
647 : :
648 : : for (;;)
649 : 0 : {
650 : : int cmpresult;
651 : 0 : bool firstsatisfies = false;
652 : :
653 [ # # ]: 0 : if (subkey->sk_attno > firstchangingattnum) /* >, not >= */
654 : 0 : break; /* unsafe, preceding attr has multiple
655 : : * distinct values */
656 : :
657 [ # # ]: 0 : if (subkey->sk_flags & SK_ISNULL)
658 : 0 : break; /* unsafe, unsatisfiable NULL subkey arg */
659 : :
660 : 0 : firstdatum = index_getattr(firsttup, subkey->sk_attno,
661 : : tupdesc, &firstnull);
662 : 0 : lastdatum = index_getattr(lasttup, subkey->sk_attno,
663 : : tupdesc, &lastnull);
664 : :
665 [ # # # # ]: 0 : if (firstnull || lastnull)
666 : : break; /* unsafe, NULL value won't satisfy subkey */
667 : :
668 : : /*
669 : : * Compare the first tuple's datum for this row compare member
670 : : */
671 : 0 : cmpresult = DatumGetInt32(FunctionCall2Coll(&subkey->sk_func,
672 : : subkey->sk_collation,
673 : : firstdatum,
674 : : subkey->sk_argument));
675 [ # # ]: 0 : if (subkey->sk_flags & SK_BT_DESC)
676 [ # # ]: 0 : INVERT_COMPARE_RESULT(cmpresult);
677 : :
678 [ # # # # ]: 0 : if (cmpresult != 0 || (subkey->sk_flags & SK_ROW_END))
679 : : {
680 : 0 : firstsatisfies = _bt_rowcompare_cmpresult(subkey,
681 : : cmpresult);
682 [ # # ]: 0 : if (!firstsatisfies)
683 : : {
684 : : /* Unsafe, firstdatum does not satisfy subkey */
685 : 0 : break;
686 : : }
687 : : }
688 : :
689 : : /*
690 : : * Compare the last tuple's datum for this row compare member
691 : : */
692 : 0 : cmpresult = DatumGetInt32(FunctionCall2Coll(&subkey->sk_func,
693 : : subkey->sk_collation,
694 : : lastdatum,
695 : : subkey->sk_argument));
696 [ # # ]: 0 : if (subkey->sk_flags & SK_BT_DESC)
697 [ # # ]: 0 : INVERT_COMPARE_RESULT(cmpresult);
698 : :
699 [ # # # # ]: 0 : if (cmpresult != 0 || (subkey->sk_flags & SK_ROW_END))
700 : : {
701 [ # # ]: 0 : if (!firstsatisfies)
702 : : {
703 : : /*
704 : : * It's only safe to set startikey beyond the row
705 : : * compare header key when both firsttup and lasttup
706 : : * satisfy the key as a whole based on the same
707 : : * deciding subkey/attribute. That can't happen now.
708 : : */
709 : 0 : break; /* unsafe */
710 : : }
711 : :
712 : 0 : satisfied = _bt_rowcompare_cmpresult(subkey, cmpresult);
713 : 0 : break; /* safe iff 'satisfied' is true */
714 : : }
715 : :
716 : : /* Move on to next row member/subkey */
717 [ # # ]: 0 : if (subkey->sk_flags & SK_ROW_END)
718 : 0 : break; /* defensive */
719 : 0 : subkey++;
720 : :
721 : : /*
722 : : * We deliberately don't check if the next subkey has the same
723 : : * strategy as this iteration's subkey (which happens when
724 : : * subkeys for both ASC and DESC columns are used together),
725 : : * nor if any subkey is marked required. This is safe because
726 : : * in general all prior index attributes must have only one
727 : : * distinct value (across all of the tuples on the page) in
728 : : * order for us to even consider any subkey's attribute.
729 : : */
730 : : }
731 : :
732 [ # # ]: 0 : if (satisfied)
733 : : {
734 : : /* Safe, row compare satisfied by every tuple on page */
735 : 5480 : continue;
736 : : }
737 : :
738 : 10076 : break; /* unsafe */
739 : : }
740 [ + + ]: 15722 : if (key->sk_strategy != BTEqualStrategyNumber)
741 : : {
742 : : /*
743 : : * Scalar inequality key.
744 : : *
745 : : * It's definitely safe for _bt_checkkeys to avoid assessing this
746 : : * inequality when the page's first and last non-pivot tuples both
747 : : * satisfy the inequality (since the same must also be true of all
748 : : * the tuples in between these two).
749 : : *
750 : : * Unlike the "=" case, it doesn't matter if this attribute has
751 : : * more than one distinct value (though it _is_ necessary for any
752 : : * and all _prior_ attributes to contain no more than one distinct
753 : : * value amongst all of the tuples from pstate.page).
754 : : */
755 [ + + ]: 2801 : if (key->sk_attno > firstchangingattnum) /* >, not >= */
756 : 230 : break; /* unsafe, preceding attr has multiple
757 : : * distinct values */
758 : :
759 : 2571 : firstdatum = index_getattr(firsttup, key->sk_attno, tupdesc, &firstnull);
760 : 2571 : lastdatum = index_getattr(lasttup, key->sk_attno, tupdesc, &lastnull);
761 : :
762 [ + + ]: 2571 : if (key->sk_flags & SK_ISNULL)
763 : : {
764 : : /* IS NOT NULL key */
765 : : Assert(key->sk_flags & SK_SEARCHNOTNULL);
766 : :
767 [ + - + - ]: 48 : if (firstnull || lastnull)
768 : : break; /* unsafe */
769 : :
770 : : /* Safe, IS NOT NULL key satisfied by every tuple */
771 : 48 : continue;
772 : : }
773 : :
774 : : /* Test firsttup */
775 [ + - ]: 2523 : if (firstnull ||
776 [ + - ]: 2523 : !DatumGetBool(FunctionCall2Coll(&key->sk_func,
777 : : key->sk_collation, firstdatum,
778 : : key->sk_argument)))
779 : : break; /* unsafe */
780 : :
781 : : /* Test lasttup */
782 [ + - ]: 2523 : if (lastnull ||
783 [ + + ]: 2523 : !DatumGetBool(FunctionCall2Coll(&key->sk_func,
784 : : key->sk_collation, lastdatum,
785 : : key->sk_argument)))
786 : : break; /* unsafe */
787 : :
788 : : /* Safe, scalar inequality satisfied by every tuple */
789 : 2457 : continue;
790 : : }
791 : :
792 : : /* Some = key (could be a scalar = key, could be an array = key) */
793 : : Assert(key->sk_strategy == BTEqualStrategyNumber);
794 : :
795 [ + + ]: 12921 : if (!(key->sk_flags & SK_SEARCHARRAY))
796 : : {
797 : : /*
798 : : * Scalar = key (possibly an IS NULL key).
799 : : *
800 : : * It is unsafe to set pstate.startikey to an ikey beyond this
801 : : * key, unless the = key is satisfied by every possible tuple on
802 : : * the page (possible only when attribute has just one distinct
803 : : * value among all tuples on the page).
804 : : */
805 [ + + ]: 10571 : if (key->sk_attno >= firstchangingattnum)
806 : 9360 : break; /* unsafe, multiple distinct attr values */
807 : :
808 : 1211 : firstdatum = index_getattr(firsttup, key->sk_attno, tupdesc,
809 : : &firstnull);
810 [ - + ]: 1211 : if (key->sk_flags & SK_ISNULL)
811 : : {
812 : : /* IS NULL key */
813 : : Assert(key->sk_flags & SK_SEARCHNULL);
814 : :
815 [ # # ]: 0 : if (!firstnull)
816 : 0 : break; /* unsafe */
817 : :
818 : : /* Safe, IS NULL key satisfied by every tuple */
819 : 0 : continue;
820 : : }
821 [ + - ]: 1211 : if (firstnull ||
822 [ + - ]: 1211 : !DatumGetBool(FunctionCall2Coll(&key->sk_func,
823 : : key->sk_collation, firstdatum,
824 : : key->sk_argument)))
825 : : break; /* unsafe */
826 : :
827 : : /* Safe, scalar = key satisfied by every tuple */
828 : 1211 : continue;
829 : : }
830 : :
831 : : /* = array key (could be a SAOP array, could be a skip array) */
832 : 2350 : array = &so->arrayKeys[arrayidx++];
833 : : Assert(array->scan_key == startikey);
834 [ + + ]: 2350 : if (array->num_elems != -1)
835 : : {
836 : : /*
837 : : * SAOP array = key.
838 : : *
839 : : * Handle this like we handle scalar = keys (though binary search
840 : : * for a matching element, to avoid relying on key's sk_argument).
841 : : */
842 [ + - ]: 377 : if (key->sk_attno >= firstchangingattnum)
843 : 377 : break; /* unsafe, multiple distinct attr values */
844 : :
845 : 0 : firstdatum = index_getattr(firsttup, key->sk_attno, tupdesc,
846 : : &firstnull);
847 : 0 : _bt_binsrch_array_skey(&so->orderProcs[startikey],
848 : : false, NoMovementScanDirection,
849 : : firstdatum, firstnull, array, key,
850 : : &result);
851 [ # # ]: 0 : if (result != 0)
852 : 0 : break; /* unsafe */
853 : :
854 : : /* Safe, SAOP = key satisfied by every tuple */
855 : 0 : start_past_saop_eq = true;
856 : 0 : continue;
857 : : }
858 : :
859 : : /*
860 : : * Skip array = key
861 : : */
862 : : Assert(key->sk_flags & SK_BT_SKIP);
863 [ + + ]: 1973 : if (array->null_elem)
864 : : {
865 : : /*
866 : : * Non-range skip array = key.
867 : : *
868 : : * Safe, non-range skip array "satisfied" by every tuple on page
869 : : * (safe even when "key->sk_attno > firstchangingattnum").
870 : : */
871 : 1764 : continue;
872 : : }
873 : :
874 : : /*
875 : : * Range skip array = key.
876 : : *
877 : : * Handle this like we handle scalar inequality keys (but avoid using
878 : : * key's sk_argument directly, as in the SAOP array case).
879 : : */
880 [ + + ]: 209 : if (key->sk_attno > firstchangingattnum) /* >, not >= */
881 : 32 : break; /* unsafe, preceding attr has multiple
882 : : * distinct values */
883 : :
884 : 177 : firstdatum = index_getattr(firsttup, key->sk_attno, tupdesc, &firstnull);
885 : 177 : lastdatum = index_getattr(lasttup, key->sk_attno, tupdesc, &lastnull);
886 : :
887 : : /* Test firsttup */
888 : 177 : _bt_binsrch_skiparray_skey(false, ForwardScanDirection,
889 : : firstdatum, firstnull, array, key,
890 : : &result);
891 [ - + ]: 177 : if (result != 0)
892 : 0 : break; /* unsafe */
893 : :
894 : : /* Test lasttup */
895 : 177 : _bt_binsrch_skiparray_skey(false, ForwardScanDirection,
896 : : lastdatum, lastnull, array, key,
897 : : &result);
898 [ + + ]: 177 : if (result != 0)
899 : 11 : break; /* unsafe */
900 : :
901 : : /* Safe, range skip array satisfied by every tuple on page */
902 : : }
903 : :
904 : : /*
905 : : * Use of forcenonrequired is typically undesirable, since it'll force
906 : : * _bt_readpage caller to read every tuple on the page -- even though, in
907 : : * general, it might well be possible to end the scan on an earlier tuple.
908 : : * However, caller must use forcenonrequired when start_past_saop_eq=true,
909 : : * since the usual required array behavior might fail to roll over to the
910 : : * SAOP array.
911 : : *
912 : : * We always prefer forcenonrequired=true during scans with skip arrays
913 : : * (except on the first page of each primitive index scan), though -- even
914 : : * when "startikey == 0". That way, _bt_advance_array_keys's low-order
915 : : * key precheck optimization can always be used (unless on the first page
916 : : * of the scan). It seems slightly preferable to check more tuples when
917 : : * that allows us to do significantly less skip array maintenance.
918 : : */
919 [ + - + + ]: 13655 : pstate->forcenonrequired = (start_past_saop_eq || so->skipScan);
920 : 13655 : pstate->startikey = startikey;
921 : :
922 : : /*
923 : : * _bt_readpage caller is required to call _bt_checkkeys against page's
924 : : * finaltup with forcenonrequired=false whenever we initially set
925 : : * forcenonrequired=true. That way the scan's arrays will reliably track
926 : : * its progress through the index's key space.
927 : : *
928 : : * We don't expect this when _bt_readpage caller has no finaltup due to
929 : : * its page being the rightmost (or the leftmost, during backwards scans).
930 : : * When we see that _bt_readpage has no finaltup, back out of everything.
931 : : */
932 : : Assert(!pstate->forcenonrequired || so->numArrayKeys);
933 [ + + + + ]: 13655 : if (pstate->forcenonrequired && !pstate->finaltup)
934 : : {
935 : 310 : pstate->forcenonrequired = false;
936 : 310 : pstate->startikey = 0;
937 : : }
938 : : }
939 : :
940 : : /*
941 : : * Test whether caller's finaltup tuple is still before the start of matches
942 : : * for the current array keys.
943 : : *
944 : : * Called at the start of reading a page during a scan with array keys, though
945 : : * only when the so->scanBehind flag was set on the scan's prior page.
946 : : *
947 : : * Returns false if the tuple is still before the start of matches. When that
948 : : * happens, caller should cut its losses and start a new primitive index scan.
949 : : * Otherwise returns true.
950 : : */
951 : : static bool
952 : 1918 : _bt_scanbehind_checkkeys(IndexScanDesc scan, ScanDirection dir,
953 : : IndexTuple finaltup)
954 : : {
955 : 1918 : Relation rel = scan->indexRelation;
956 : 1918 : TupleDesc tupdesc = RelationGetDescr(rel);
957 : 1918 : BTScanOpaque so = (BTScanOpaque) scan->opaque;
958 [ + + ]: 1918 : int nfinaltupatts = BTreeTupleGetNAtts(finaltup, rel);
959 : : bool scanBehind;
960 : :
961 : : Assert(so->numArrayKeys);
962 : :
963 [ + + ]: 1918 : if (_bt_tuple_before_array_skeys(scan, dir, finaltup, tupdesc,
964 : : nfinaltupatts, false, 0, &scanBehind))
965 : 280 : return false;
966 : :
967 : : /*
968 : : * If scanBehind was set, all of the untruncated attribute values from
969 : : * finaltup that correspond to an array match the array's current element,
970 : : * but there are other keys associated with truncated suffix attributes.
971 : : * Array advancement must have incremented the scan's arrays on the
972 : : * previous page, resulting in a set of array keys that happen to be an
973 : : * exact match for the current page high key's untruncated prefix values.
974 : : *
975 : : * This page definitely doesn't contain tuples that the scan will need to
976 : : * return. The next page may or may not contain relevant tuples. Handle
977 : : * this by cutting our losses and starting a new primscan.
978 : : */
979 [ - + ]: 1638 : if (scanBehind)
980 : 0 : return false;
981 : :
982 [ + + ]: 1638 : if (!so->oppositeDirCheck)
983 : 1564 : return true;
984 : :
985 : 74 : return _bt_oppodir_checkkeys(scan, dir, finaltup);
986 : : }
987 : :
988 : : /*
989 : : * Test whether an indextuple fails to satisfy an inequality required in the
990 : : * opposite direction only.
991 : : *
992 : : * Caller's finaltup tuple is the page high key (for forwards scans), or the
993 : : * first non-pivot tuple (for backwards scans). Called during scans with
994 : : * required array keys and required opposite-direction inequalities.
995 : : *
996 : : * Returns false if an inequality scan key required in the opposite direction
997 : : * only isn't satisfied (and any earlier required scan keys are satisfied).
998 : : * Otherwise returns true.
999 : : *
1000 : : * An unsatisfied inequality required in the opposite direction only might
1001 : : * well enable skipping over many leaf pages, provided another _bt_first call
1002 : : * takes place. This type of unsatisfied inequality won't usually cause
1003 : : * _bt_checkkeys to stop the scan to consider array advancement/starting a new
1004 : : * primitive index scan.
1005 : : */
1006 : : static bool
1007 : 2930 : _bt_oppodir_checkkeys(IndexScanDesc scan, ScanDirection dir,
1008 : : IndexTuple finaltup)
1009 : : {
1010 : 2930 : Relation rel = scan->indexRelation;
1011 : 2930 : TupleDesc tupdesc = RelationGetDescr(rel);
1012 : 2930 : BTScanOpaque so = (BTScanOpaque) scan->opaque;
1013 [ + - ]: 2930 : int nfinaltupatts = BTreeTupleGetNAtts(finaltup, rel);
1014 : : bool continuescan;
1015 : 2930 : ScanDirection flipped = -dir;
1016 : 2930 : int ikey = 0;
1017 : :
1018 : : Assert(so->numArrayKeys);
1019 : :
1020 : 2930 : _bt_check_compare(scan, flipped, finaltup, nfinaltupatts, tupdesc, false,
1021 : : false, &continuescan,
1022 : : &ikey);
1023 : :
1024 [ + + + + ]: 2930 : if (!continuescan && so->keyData[ikey].sk_strategy != BTEqualStrategyNumber)
1025 : 1 : return false;
1026 : :
1027 : 2929 : return true;
1028 : : }
1029 : :
1030 : : /* Save an index item into so->currPos.items[itemIndex] */
1031 : : static void
1032 : 30905673 : _bt_saveitem(BTScanOpaque so, int itemIndex,
1033 : : OffsetNumber offnum, IndexTuple itup)
1034 : : {
1035 : 30905673 : BTScanPosItem *currItem = &so->currPos.items[itemIndex];
1036 : :
1037 : : Assert(!BTreeTupleIsPivot(itup) && !BTreeTupleIsPosting(itup));
1038 : :
1039 : 30905673 : currItem->heapTid = itup->t_tid;
1040 : 30905673 : currItem->indexOffset = offnum;
1041 [ + + ]: 30905673 : if (so->currTuples)
1042 : : {
1043 : 14375789 : Size itupsz = IndexTupleSize(itup);
1044 : :
1045 : 14375789 : currItem->tupleOffset = so->currPos.nextTupleOffset;
1046 : 14375789 : memcpy(so->currTuples + so->currPos.nextTupleOffset, itup, itupsz);
1047 : 14375789 : so->currPos.nextTupleOffset += MAXALIGN(itupsz);
1048 : : }
1049 : 30905673 : }
1050 : :
1051 : : /*
1052 : : * Setup state to save TIDs/items from a single posting list tuple.
1053 : : *
1054 : : * Saves an index item into so->currPos.items[itemIndex] for TID that is
1055 : : * returned to scan first. Second or subsequent TIDs for posting list should
1056 : : * be saved by calling _bt_savepostingitem().
1057 : : *
1058 : : * Returns an offset into tuple storage space that main tuple is stored at if
1059 : : * needed.
1060 : : */
1061 : : static int
1062 : 354990 : _bt_setuppostingitems(BTScanOpaque so, int itemIndex, OffsetNumber offnum,
1063 : : const ItemPointerData *heapTid, IndexTuple itup)
1064 : : {
1065 : 354990 : BTScanPosItem *currItem = &so->currPos.items[itemIndex];
1066 : :
1067 : : Assert(BTreeTupleIsPosting(itup));
1068 : :
1069 : 354990 : currItem->heapTid = *heapTid;
1070 : 354990 : currItem->indexOffset = offnum;
1071 [ + + ]: 354990 : if (so->currTuples)
1072 : : {
1073 : : /* Save base IndexTuple (truncate posting list) */
1074 : : IndexTuple base;
1075 : 118438 : Size itupsz = BTreeTupleGetPostingOffset(itup);
1076 : :
1077 : 118438 : itupsz = MAXALIGN(itupsz);
1078 : 118438 : currItem->tupleOffset = so->currPos.nextTupleOffset;
1079 : 118438 : base = (IndexTuple) (so->currTuples + so->currPos.nextTupleOffset);
1080 : 118438 : memcpy(base, itup, itupsz);
1081 : : /* Defensively reduce work area index tuple header size */
1082 : 118438 : base->t_info &= ~INDEX_SIZE_MASK;
1083 : 118438 : base->t_info |= itupsz;
1084 : 118438 : so->currPos.nextTupleOffset += itupsz;
1085 : :
1086 : 118438 : return currItem->tupleOffset;
1087 : : }
1088 : :
1089 : 236552 : return 0;
1090 : : }
1091 : :
1092 : : /*
1093 : : * Save an index item into so->currPos.items[itemIndex] for current posting
1094 : : * tuple.
1095 : : *
1096 : : * Assumes that _bt_setuppostingitems() has already been called for current
1097 : : * posting list tuple. Caller passes its return value as tupleOffset.
1098 : : */
1099 : : static inline void
1100 : 1700186 : _bt_savepostingitem(BTScanOpaque so, int itemIndex, OffsetNumber offnum,
1101 : : ItemPointer heapTid, int tupleOffset)
1102 : : {
1103 : 1700186 : BTScanPosItem *currItem = &so->currPos.items[itemIndex];
1104 : :
1105 : 1700186 : currItem->heapTid = *heapTid;
1106 : 1700186 : currItem->indexOffset = offnum;
1107 : :
1108 : : /*
1109 : : * Have index-only scans return the same base IndexTuple for every TID
1110 : : * that originates from the same posting list
1111 : : */
1112 [ + + ]: 1700186 : if (so->currTuples)
1113 : 662588 : currItem->tupleOffset = tupleOffset;
1114 : 1700186 : }
1115 : :
1116 : : #define LOOK_AHEAD_REQUIRED_RECHECKS 3
1117 : : #define LOOK_AHEAD_DEFAULT_DISTANCE 5
1118 : : #define NSKIPADVANCES_THRESHOLD 3
1119 : :
1120 : : /*
1121 : : * Test whether an indextuple satisfies all the scankey conditions.
1122 : : *
1123 : : * Returns true if so, false if not. If not,
1124 : : * we also determine whether there's any need to continue the scan beyond
1125 : : * this tuple, and set pstate.continuescan accordingly. See comments for
1126 : : * _bt_preprocess_keys() about how this is done.
1127 : : *
1128 : : * Forward scan callers can pass a high key tuple in the hopes of having
1129 : : * us set pstate.continuescan to false, avoiding an unnecessary visit to
1130 : : * the page to the right.
1131 : : *
1132 : : * Advances the scan's array keys when necessary for arrayKeys=true callers.
1133 : : * Scans without any array keys must always pass arrayKeys=false.
1134 : : *
1135 : : * Also stops and starts primitive index scans for arrayKeys=true callers.
1136 : : * Scans with array keys are required to set up page state that helps us with
1137 : : * this. The page's finaltup tuple (the page high key for a forward scan, or
1138 : : * the page's first non-pivot tuple for a backward scan) must be set in
1139 : : * pstate.finaltup ahead of the first call here for the page. Set it to
1140 : : * NULL for rightmost page (or the leftmost page for backwards scans).
1141 : : *
1142 : : * scan: index scan descriptor (containing a search-type scankey)
1143 : : * pstate: page level input and output parameters
1144 : : * arrayKeys: should we advance the scan's array keys if necessary?
1145 : : * tuple: index tuple to test
1146 : : * tupnatts: number of attributes in tupnatts (high key may be truncated)
1147 : : */
1148 : : static bool
1149 : 39728259 : _bt_checkkeys(IndexScanDesc scan, BTReadPageState *pstate, bool arrayKeys,
1150 : : IndexTuple tuple, int tupnatts)
1151 : : {
1152 : 39728259 : TupleDesc tupdesc = RelationGetDescr(scan->indexRelation);
1153 : 39728259 : BTScanOpaque so PG_USED_FOR_ASSERTS_ONLY = (BTScanOpaque) scan->opaque;
1154 : 39728259 : ScanDirection dir = pstate->dir;
1155 : 39728259 : int ikey = pstate->startikey;
1156 : : bool res;
1157 : :
1158 : : Assert(BTreeTupleGetNAtts(tuple, scan->indexRelation) == tupnatts);
1159 : : Assert(!so->needPrimScan && !so->scanBehind && !so->oppositeDirCheck);
1160 : : Assert(arrayKeys || so->numArrayKeys == 0);
1161 : :
1162 : 39728259 : res = _bt_check_compare(scan, dir, tuple, tupnatts, tupdesc, arrayKeys,
1163 : 39728259 : pstate->forcenonrequired, &pstate->continuescan,
1164 : : &ikey);
1165 : :
1166 : : /*
1167 : : * If _bt_check_compare relied on the pstate.startikey optimization, call
1168 : : * again (in assert-enabled builds) to verify it didn't affect our answer.
1169 : : *
1170 : : * Note: we can't do this when !pstate.forcenonrequired, since any arrays
1171 : : * before pstate.startikey won't have advanced on this page at all.
1172 : : */
1173 : : Assert(!pstate->forcenonrequired || arrayKeys);
1174 : : #ifdef USE_ASSERT_CHECKING
1175 : : if (pstate->startikey > 0 && !pstate->forcenonrequired)
1176 : : {
1177 : : bool dres,
1178 : : dcontinuescan;
1179 : : int dikey = 0;
1180 : :
1181 : : /* Pass advancenonrequired=false to avoid array side-effects */
1182 : : dres = _bt_check_compare(scan, dir, tuple, tupnatts, tupdesc, false,
1183 : : pstate->forcenonrequired, &dcontinuescan,
1184 : : &dikey);
1185 : : Assert(res == dres);
1186 : : Assert(pstate->continuescan == dcontinuescan);
1187 : :
1188 : : /*
1189 : : * Should also get the same ikey result. We need a slightly weaker
1190 : : * assertion during arrayKeys calls, since they might be using an
1191 : : * array that couldn't be marked required during preprocessing.
1192 : : */
1193 : : Assert(arrayKeys || ikey == dikey);
1194 : : Assert(ikey <= dikey);
1195 : : }
1196 : : #endif
1197 : :
1198 : : /*
1199 : : * Only one _bt_check_compare call is required in the common case where
1200 : : * there are no equality strategy array scan keys. With array keys, we
1201 : : * can only accept _bt_check_compare's answer unreservedly when it set
1202 : : * pstate.continuescan=true.
1203 : : */
1204 [ + + + + ]: 39728259 : if (!arrayKeys || pstate->continuescan)
1205 : 39122763 : return res;
1206 : :
1207 : : /*
1208 : : * _bt_check_compare call set continuescan=false in the presence of
1209 : : * equality type array keys. This could mean that the tuple is just past
1210 : : * the end of matches for the current array keys.
1211 : : *
1212 : : * It's also possible that the scan is still _before_ the _start_ of
1213 : : * tuples matching the current set of array keys. Check for that first.
1214 : : */
1215 : : Assert(!pstate->forcenonrequired);
1216 [ + + ]: 605496 : if (_bt_tuple_before_array_skeys(scan, dir, tuple, tupdesc, tupnatts, true,
1217 : : ikey, NULL))
1218 : : {
1219 : : /* Override _bt_check_compare, continue primitive scan */
1220 : 78276 : pstate->continuescan = true;
1221 : :
1222 : : /*
1223 : : * We will end up here repeatedly given a group of tuples > the
1224 : : * previous array keys and < the now-current keys (for a backwards
1225 : : * scan it's just the same, though the operators swap positions).
1226 : : *
1227 : : * We must avoid allowing this linear search process to scan very many
1228 : : * tuples from well before the start of tuples matching the current
1229 : : * array keys (or from well before the point where we'll once again
1230 : : * have to advance the scan's array keys).
1231 : : *
1232 : : * We keep the overhead under control by speculatively "looking ahead"
1233 : : * to later still-unscanned items from this same leaf page. We'll
1234 : : * only attempt this once the number of tuples that the linear search
1235 : : * process has examined starts to get out of hand.
1236 : : */
1237 : 78276 : pstate->rechecks++;
1238 [ + + ]: 78276 : if (pstate->rechecks >= LOOK_AHEAD_REQUIRED_RECHECKS)
1239 : : {
1240 : : /* See if we should skip ahead within the current leaf page */
1241 : 34488 : _bt_checkkeys_look_ahead(scan, pstate, tupnatts, tupdesc);
1242 : :
1243 : : /*
1244 : : * Might have set pstate.skip to a later page offset. When that
1245 : : * happens then _bt_readpage caller will inexpensively skip ahead
1246 : : * to a later tuple from the same page (the one just after the
1247 : : * tuple we successfully "looked ahead" to).
1248 : : */
1249 : : }
1250 : :
1251 : : /* This indextuple doesn't match the current qual, in any case */
1252 : 78276 : return false;
1253 : : }
1254 : :
1255 : : /*
1256 : : * Caller's tuple is >= the current set of array keys and other equality
1257 : : * constraint scan keys (or <= if this is a backwards scan). It's now
1258 : : * clear that we _must_ advance any required array keys in lockstep with
1259 : : * the scan.
1260 : : */
1261 : 527220 : return _bt_advance_array_keys(scan, pstate, tuple, tupnatts, tupdesc,
1262 : : ikey, true);
1263 : : }
1264 : :
1265 : : /*
1266 : : * Test whether an indextuple satisfies current scan condition.
1267 : : *
1268 : : * Return true if so, false if not. If not, also sets *continuescan to false
1269 : : * when it's also not possible for any later tuples to pass the current qual
1270 : : * (with the scan's current set of array keys, in the current scan direction),
1271 : : * in addition to setting *ikey to the so->keyData[] subscript/offset for the
1272 : : * unsatisfied scan key (needed when caller must consider advancing the scan's
1273 : : * array keys).
1274 : : *
1275 : : * This is a subroutine for _bt_checkkeys. We provisionally assume that
1276 : : * reaching the end of the current set of required keys (in particular the
1277 : : * current required array keys) ends the ongoing (primitive) index scan.
1278 : : * Callers without array keys should just end the scan right away when they
1279 : : * find that continuescan has been set to false here by us. Things are more
1280 : : * complicated for callers with array keys.
1281 : : *
1282 : : * Callers with array keys must first consider advancing the arrays when
1283 : : * continuescan has been set to false here by us. They must then consider if
1284 : : * it really does make sense to end the current (primitive) index scan, in
1285 : : * light of everything that is known at that point. (In general when we set
1286 : : * continuescan=false for these callers it must be treated as provisional.)
1287 : : *
1288 : : * We deal with advancing unsatisfied non-required arrays directly, though.
1289 : : * This is safe, since by definition non-required keys can't end the scan.
1290 : : * This is just how we determine if non-required arrays are just unsatisfied
1291 : : * by the current array key, or if they're truly unsatisfied (that is, if
1292 : : * they're unsatisfied by every possible array key).
1293 : : *
1294 : : * Pass advancenonrequired=false to avoid all array related side effects.
1295 : : * This allows _bt_advance_array_keys caller to avoid infinite recursion.
1296 : : *
1297 : : * Pass forcenonrequired=true to instruct us to treat all keys as nonrequired.
1298 : : * This is used to make it safe to temporarily stop properly maintaining the
1299 : : * scan's required arrays. _bt_checkkeys caller (_bt_readpage, actually)
1300 : : * determines a prefix of keys that must satisfy every possible corresponding
1301 : : * index attribute value from its page, which is passed to us via *ikey arg
1302 : : * (this is the first key that might be unsatisfied by tuples on the page).
1303 : : * Obviously, we won't maintain any array keys from before *ikey, so it's
1304 : : * quite possible for such arrays to "fall behind" the index's keyspace.
1305 : : * Caller will need to "catch up" by passing forcenonrequired=true (alongside
1306 : : * an *ikey=0) once the page's finaltup is reached.
1307 : : *
1308 : : * Note: it's safe to pass an *ikey > 0 with forcenonrequired=false, but only
1309 : : * when caller determines that it won't affect array maintenance.
1310 : : */
1311 : : static bool
1312 : 40163998 : _bt_check_compare(IndexScanDesc scan, ScanDirection dir,
1313 : : IndexTuple tuple, int tupnatts, TupleDesc tupdesc,
1314 : : bool advancenonrequired, bool forcenonrequired,
1315 : : bool *continuescan, int *ikey)
1316 : : {
1317 : 40163998 : BTScanOpaque so = (BTScanOpaque) scan->opaque;
1318 : :
1319 : 40163998 : *continuescan = true; /* default assumption */
1320 : :
1321 [ + + ]: 76562775 : for (; *ikey < so->numberOfKeys; (*ikey)++)
1322 : : {
1323 : 45261426 : ScanKey key = so->keyData + *ikey;
1324 : : Datum datum;
1325 : : bool isNull;
1326 : 45261426 : bool requiredSameDir = false,
1327 : 45261426 : requiredOppositeDirOnly = false;
1328 : :
1329 : : /*
1330 : : * Check if the key is required in the current scan direction, in the
1331 : : * opposite scan direction _only_, or in neither direction (except
1332 : : * when we're forced to treat all scan keys as nonrequired)
1333 : : */
1334 [ + + ]: 45261426 : if (forcenonrequired)
1335 : : {
1336 : : /* treating scan's keys as non-required */
1337 : : }
1338 [ + + + + ]: 44952066 : else if (((key->sk_flags & SK_BT_REQFWD) && ScanDirectionIsForward(dir)) ||
1339 [ + + + + ]: 9116091 : ((key->sk_flags & SK_BT_REQBKWD) && ScanDirectionIsBackward(dir)))
1340 : 35852451 : requiredSameDir = true;
1341 [ + + - + ]: 9099615 : else if (((key->sk_flags & SK_BT_REQFWD) && ScanDirectionIsBackward(dir)) ||
1342 [ + - + - ]: 3801707 : ((key->sk_flags & SK_BT_REQBKWD) && ScanDirectionIsForward(dir)))
1343 : 9099615 : requiredOppositeDirOnly = true;
1344 : :
1345 [ + + ]: 45261426 : if (key->sk_attno > tupnatts)
1346 : : {
1347 : : /*
1348 : : * This attribute is truncated (must be high key). The value for
1349 : : * this attribute in the first non-pivot tuple on the page to the
1350 : : * right could be any possible value. Assume that truncated
1351 : : * attribute passes the qual.
1352 : : */
1353 : : Assert(BTreeTupleIsPivot(tuple));
1354 : 11974054 : continue;
1355 : : }
1356 : :
1357 : : /*
1358 : : * A skip array scan key uses one of several sentinel values. We just
1359 : : * fall back on _bt_tuple_before_array_skeys when we see such a value.
1360 : : */
1361 [ + + ]: 45259723 : if (key->sk_flags & (SK_BT_MINVAL | SK_BT_MAXVAL |
1362 : : SK_BT_NEXT | SK_BT_PRIOR))
1363 : : {
1364 : : Assert(key->sk_flags & SK_SEARCHARRAY);
1365 : : Assert(key->sk_flags & SK_BT_SKIP);
1366 : : Assert(requiredSameDir || forcenonrequired);
1367 : :
1368 : : /*
1369 : : * Cannot fall back on _bt_tuple_before_array_skeys when we're
1370 : : * treating the scan's keys as nonrequired, though. Just handle
1371 : : * this like any other non-required equality-type array key.
1372 : : */
1373 [ + + ]: 17240 : if (forcenonrequired)
1374 : 8862649 : return _bt_advance_array_keys(scan, NULL, tuple, tupnatts,
1375 : : tupdesc, *ikey, false);
1376 : :
1377 : 15888 : *continuescan = false;
1378 : 15888 : return false;
1379 : : }
1380 : :
1381 : : /* row-comparison keys need special processing */
1382 [ + + ]: 45242483 : if (key->sk_flags & SK_ROW_HEADER)
1383 : : {
1384 [ + + ]: 1636 : if (_bt_check_rowcompare(key, tuple, tupnatts, tupdesc, dir,
1385 : : forcenonrequired, continuescan))
1386 : 1592 : continue;
1387 : 44 : return false;
1388 : : }
1389 : :
1390 : 45240847 : datum = index_getattr(tuple,
1391 : 45240847 : key->sk_attno,
1392 : : tupdesc,
1393 : : &isNull);
1394 : :
1395 [ + + ]: 45240847 : if (key->sk_flags & SK_ISNULL)
1396 : : {
1397 : : /* Handle IS NULL/NOT NULL tests */
1398 [ + + ]: 11982607 : if (key->sk_flags & SK_SEARCHNULL)
1399 : : {
1400 [ + + ]: 12093 : if (isNull)
1401 : 293 : continue; /* tuple satisfies this qual */
1402 : : }
1403 : : else
1404 : : {
1405 : : Assert(key->sk_flags & SK_SEARCHNOTNULL);
1406 : : Assert(!(key->sk_flags & SK_BT_SKIP));
1407 [ + + ]: 11970514 : if (!isNull)
1408 : 11970466 : continue; /* tuple satisfies this qual */
1409 : : }
1410 : :
1411 : : /*
1412 : : * Tuple fails this qual. If it's a required qual for the current
1413 : : * scan direction, then we can conclude no further tuples will
1414 : : * pass, either.
1415 : : */
1416 [ + + ]: 11848 : if (requiredSameDir)
1417 : 136 : *continuescan = false;
1418 [ - + ]: 11712 : else if (unlikely(key->sk_flags & SK_BT_SKIP))
1419 : : {
1420 : : /*
1421 : : * If we're treating scan keys as nonrequired, and encounter a
1422 : : * skip array scan key whose current element is NULL, then it
1423 : : * must be a non-range skip array. It must be satisfied, so
1424 : : * there's no need to call _bt_advance_array_keys to check.
1425 : : */
1426 : : Assert(forcenonrequired && *ikey > 0);
1427 : 0 : continue;
1428 : : }
1429 : :
1430 : : /*
1431 : : * This indextuple doesn't match the qual.
1432 : : */
1433 : 11848 : return false;
1434 : : }
1435 : :
1436 [ + + ]: 33258240 : if (isNull)
1437 : : {
1438 : : /*
1439 : : * Scalar scan key isn't satisfied by NULL tuple value.
1440 : : *
1441 : : * If we're treating scan keys as nonrequired, and key is for a
1442 : : * skip array, then we must attempt to advance the array to NULL
1443 : : * (if we're successful then the tuple might match the qual).
1444 : : */
1445 [ - + - - : 152 : if (unlikely(forcenonrequired && key->sk_flags & SK_BT_SKIP))
- + ]
1446 : 0 : return _bt_advance_array_keys(scan, NULL, tuple, tupnatts,
1447 : : tupdesc, *ikey, false);
1448 : :
1449 [ - + ]: 152 : if (key->sk_flags & SK_BT_NULLS_FIRST)
1450 : : {
1451 : : /*
1452 : : * Since NULLs are sorted before non-NULLs, we know we have
1453 : : * reached the lower limit of the range of values for this
1454 : : * index attr. On a backward scan, we can stop if this qual
1455 : : * is one of the "must match" subset. We can stop regardless
1456 : : * of whether the qual is > or <, so long as it's required,
1457 : : * because it's not possible for any future tuples to pass. On
1458 : : * a forward scan, however, we must keep going, because we may
1459 : : * have initially positioned to the start of the index.
1460 : : * (_bt_advance_array_keys also relies on this behavior during
1461 : : * forward scans.)
1462 : : */
1463 [ # # # # : 0 : if ((requiredSameDir || requiredOppositeDirOnly) &&
# # ]
1464 : : ScanDirectionIsBackward(dir))
1465 : 0 : *continuescan = false;
1466 : : }
1467 : : else
1468 : : {
1469 : : /*
1470 : : * Since NULLs are sorted after non-NULLs, we know we have
1471 : : * reached the upper limit of the range of values for this
1472 : : * index attr. On a forward scan, we can stop if this qual is
1473 : : * one of the "must match" subset. We can stop regardless of
1474 : : * whether the qual is > or <, so long as it's required,
1475 : : * because it's not possible for any future tuples to pass. On
1476 : : * a backward scan, however, we must keep going, because we
1477 : : * may have initially positioned to the end of the index.
1478 : : * (_bt_advance_array_keys also relies on this behavior during
1479 : : * backward scans.)
1480 : : */
1481 [ + + + - : 152 : if ((requiredSameDir || requiredOppositeDirOnly) &&
+ + ]
1482 : : ScanDirectionIsForward(dir))
1483 : 148 : *continuescan = false;
1484 : : }
1485 : :
1486 : : /*
1487 : : * This indextuple doesn't match the qual.
1488 : : */
1489 : 152 : return false;
1490 : : }
1491 : :
1492 [ + + ]: 33258088 : if (!DatumGetBool(FunctionCall2Coll(&key->sk_func, key->sk_collation,
1493 : : datum, key->sk_argument)))
1494 : : {
1495 : : /*
1496 : : * Tuple fails this qual. If it's a required qual for the current
1497 : : * scan direction, then we can conclude no further tuples will
1498 : : * pass, either.
1499 : : */
1500 [ + + ]: 8833365 : if (requiredSameDir)
1501 : 8556098 : *continuescan = false;
1502 : :
1503 : : /*
1504 : : * If this is a non-required equality-type array key, the tuple
1505 : : * needs to be checked against every possible array key. Handle
1506 : : * this by "advancing" the scan key's array to a matching value
1507 : : * (if we're successful then the tuple might match the qual).
1508 : : */
1509 [ + + ]: 277267 : else if (advancenonrequired &&
1510 [ + + ]: 272305 : key->sk_strategy == BTEqualStrategyNumber &&
1511 [ + + ]: 223392 : (key->sk_flags & SK_SEARCHARRAY))
1512 : 4679 : return _bt_advance_array_keys(scan, NULL, tuple, tupnatts,
1513 : : tupdesc, *ikey, false);
1514 : :
1515 : : /*
1516 : : * This indextuple doesn't match the qual.
1517 : : */
1518 : 8828686 : return false;
1519 : : }
1520 : : }
1521 : :
1522 : : /* If we get here, the tuple passes all index quals. */
1523 : 31301349 : return true;
1524 : : }
1525 : :
1526 : : /*
1527 : : * Test whether an indextuple satisfies a row-comparison scan condition.
1528 : : *
1529 : : * Return true if so, false if not. If not, also clear *continuescan if
1530 : : * it's not possible for any future tuples in the current scan direction
1531 : : * to pass the qual.
1532 : : *
1533 : : * This is a subroutine for _bt_checkkeys/_bt_check_compare. Caller passes us
1534 : : * a row compare header key taken from so->keyData[].
1535 : : *
1536 : : * Row value comparisons can be described in terms of logical expansions that
1537 : : * use only scalar operators. Consider the following example row comparison:
1538 : : *
1539 : : * "(a, b, c) > (7, 'bar', 62)"
1540 : : *
1541 : : * This can be evaluated as:
1542 : : *
1543 : : * "(a = 7 AND b = 'bar' AND c > 62) OR (a = 7 AND b > 'bar') OR (a > 7)".
1544 : : *
1545 : : * Notice that this condition is satisfied by _all_ rows that satisfy "a > 7",
1546 : : * and by a subset of all rows that satisfy "a >= 7" (possibly all such rows).
1547 : : * It _can't_ be satisfied by other rows (where "a < 7" or where "a IS NULL").
1548 : : * A row comparison header key can therefore often be treated as if it was a
1549 : : * simple scalar inequality on the row compare's most significant column.
1550 : : * (For example, _bt_advance_array_keys and most preprocessing routines treat
1551 : : * row compares like any other same-strategy inequality on the same column.)
1552 : : *
1553 : : * Things get more complicated for our row compare given a row where "a = 7".
1554 : : * Note that a row compare isn't necessarily satisfied by _every_ tuple that
1555 : : * appears between the first and last satisfied tuple returned by the scan,
1556 : : * due to the way that its lower-order subkeys are only conditionally applied.
1557 : : * A forwards scan that uses our example qual might initially return a tuple
1558 : : * "(a, b, c) = (7, 'zebra', 54)". But it won't subsequently return a tuple
1559 : : * "(a, b, c) = (7, NULL, 1)" located to the right of the first matching tuple
1560 : : * (assume that "b" was declared NULLS LAST here). The scan will only return
1561 : : * additional matches upon reaching tuples where "a > 7". If you rereview our
1562 : : * example row comparison's logical expansion, you'll understand why this is.
1563 : : * (Here we assume that all subkeys could be marked required, guaranteeing
1564 : : * that row comparison order matches index order. This is the common case.)
1565 : : *
1566 : : * Note that a row comparison header key behaves _exactly_ the same as a
1567 : : * similar scalar inequality key on the row's most significant column once the
1568 : : * scan reaches the point where it no longer needs to evaluate lower-order
1569 : : * subkeys (or before the point where it starts needing to evaluate them).
1570 : : * For example, once a forwards scan that uses our example qual reaches the
1571 : : * first tuple "a > 7", we'll behave in just the same way as our caller would
1572 : : * behave with a similar scalar inequality "a > 7" for the remainder of the
1573 : : * scan (assuming that the scan never changes direction/never goes backwards).
1574 : : * We'll even set continuescan=false according to exactly the same rules as
1575 : : * the ones our caller applies with simple scalar inequalities, including the
1576 : : * rules it applies when NULL tuple values don't satisfy an inequality qual.
1577 : : */
1578 : : static bool
1579 : 1636 : _bt_check_rowcompare(ScanKey header, IndexTuple tuple, int tupnatts,
1580 : : TupleDesc tupdesc, ScanDirection dir,
1581 : : bool forcenonrequired, bool *continuescan)
1582 : : {
1583 : 1636 : ScanKey subkey = (ScanKey) DatumGetPointer(header->sk_argument);
1584 : 1636 : int32 cmpresult = 0;
1585 : : bool result;
1586 : :
1587 : : /* First subkey should be same as the header says */
1588 : : Assert(header->sk_flags & SK_ROW_HEADER);
1589 : : Assert(subkey->sk_attno == header->sk_attno);
1590 : : Assert(subkey->sk_strategy == header->sk_strategy);
1591 : :
1592 : : /* Loop over columns of the row condition */
1593 : : for (;;)
1594 : 160 : {
1595 : : Datum datum;
1596 : : bool isNull;
1597 : :
1598 : : Assert(subkey->sk_flags & SK_ROW_MEMBER);
1599 : :
1600 : : /* When a NULL row member is compared, the row never matches */
1601 [ + + ]: 1796 : if (subkey->sk_flags & SK_ISNULL)
1602 : : {
1603 : : /*
1604 : : * Unlike the simple-scankey case, this isn't a disallowed case
1605 : : * (except when it's the first row element that has the NULL arg).
1606 : : * But it can never match. If all the earlier row comparison
1607 : : * columns are required for the scan direction, we can stop the
1608 : : * scan, because there can't be another tuple that will succeed.
1609 : : */
1610 : : Assert(subkey != (ScanKey) DatumGetPointer(header->sk_argument));
1611 : 8 : subkey--;
1612 [ + - ]: 8 : if (forcenonrequired)
1613 : : {
1614 : : /* treating scan's keys as non-required */
1615 : : }
1616 [ + + + - ]: 8 : else if ((subkey->sk_flags & SK_BT_REQFWD) &&
1617 : : ScanDirectionIsForward(dir))
1618 : 4 : *continuescan = false;
1619 [ + - + - ]: 4 : else if ((subkey->sk_flags & SK_BT_REQBKWD) &&
1620 : : ScanDirectionIsBackward(dir))
1621 : 4 : *continuescan = false;
1622 : 44 : return false;
1623 : : }
1624 : :
1625 [ + + ]: 1788 : if (subkey->sk_attno > tupnatts)
1626 : : {
1627 : : /*
1628 : : * This attribute is truncated (must be high key). The value for
1629 : : * this attribute in the first non-pivot tuple on the page to the
1630 : : * right could be any possible value. Assume that truncated
1631 : : * attribute passes the qual.
1632 : : */
1633 : : Assert(BTreeTupleIsPivot(tuple));
1634 : 4 : return true;
1635 : : }
1636 : :
1637 : 1784 : datum = index_getattr(tuple,
1638 : 1784 : subkey->sk_attno,
1639 : : tupdesc,
1640 : : &isNull);
1641 : :
1642 [ + + ]: 1784 : if (isNull)
1643 : : {
1644 : : int reqflags;
1645 : :
1646 [ + - ]: 32 : if (forcenonrequired)
1647 : : {
1648 : : /* treating scan's keys as non-required */
1649 : : }
1650 [ - + ]: 32 : else if (subkey->sk_flags & SK_BT_NULLS_FIRST)
1651 : : {
1652 : : /*
1653 : : * Since NULLs are sorted before non-NULLs, we know we have
1654 : : * reached the lower limit of the range of values for this
1655 : : * index attr. On a backward scan, we can stop if this qual
1656 : : * is one of the "must match" subset. However, on a forwards
1657 : : * scan, we must keep going, because we may have initially
1658 : : * positioned to the start of the index.
1659 : : *
1660 : : * All required NULLS FIRST > row members can use NULL tuple
1661 : : * values to end backwards scans, just like with other values.
1662 : : * A qual "WHERE (a, b, c) > (9, 42, 'foo')" can terminate a
1663 : : * backwards scan upon reaching the index's rightmost "a = 9"
1664 : : * tuple whose "b" column contains a NULL (if not sooner).
1665 : : * Since "b" is NULLS FIRST, we can treat its NULLs as "<" 42.
1666 : : */
1667 : 0 : reqflags = SK_BT_REQBKWD;
1668 : :
1669 : : /*
1670 : : * When a most significant required NULLS FIRST < row compare
1671 : : * member sees NULL tuple values during a backwards scan, it
1672 : : * signals the end of matches for the whole row compare/scan.
1673 : : * A qual "WHERE (a, b, c) < (9, 42, 'foo')" will terminate a
1674 : : * backwards scan upon reaching the rightmost tuple whose "a"
1675 : : * column has a NULL. The "a" NULL value is "<" 9, and yet
1676 : : * our < row compare will still end the scan. (This isn't
1677 : : * safe with later/lower-order row members. Notice that it
1678 : : * can only happen with an "a" NULL some time after the scan
1679 : : * completely stops needing to use its "b" and "c" members.)
1680 : : */
1681 [ # # ]: 0 : if (subkey == (ScanKey) DatumGetPointer(header->sk_argument))
1682 : 0 : reqflags |= SK_BT_REQFWD; /* safe, first row member */
1683 : :
1684 [ # # # # ]: 0 : if ((subkey->sk_flags & reqflags) &&
1685 : : ScanDirectionIsBackward(dir))
1686 : 0 : *continuescan = false;
1687 : : }
1688 : : else
1689 : : {
1690 : : /*
1691 : : * Since NULLs are sorted after non-NULLs, we know we have
1692 : : * reached the upper limit of the range of values for this
1693 : : * index attr. On a forward scan, we can stop if this qual is
1694 : : * one of the "must match" subset. However, on a backward
1695 : : * scan, we must keep going, because we may have initially
1696 : : * positioned to the end of the index.
1697 : : *
1698 : : * All required NULLS LAST < row members can use NULL tuple
1699 : : * values to end forwards scans, just like with other values.
1700 : : * A qual "WHERE (a, b, c) < (9, 42, 'foo')" can terminate a
1701 : : * forwards scan upon reaching the index's leftmost "a = 9"
1702 : : * tuple whose "b" column contains a NULL (if not sooner).
1703 : : * Since "b" is NULLS LAST, we can treat its NULLs as ">" 42.
1704 : : */
1705 : 32 : reqflags = SK_BT_REQFWD;
1706 : :
1707 : : /*
1708 : : * When a most significant required NULLS LAST > row compare
1709 : : * member sees NULL tuple values during a forwards scan, it
1710 : : * signals the end of matches for the whole row compare/scan.
1711 : : * A qual "WHERE (a, b, c) > (9, 42, 'foo')" will terminate a
1712 : : * forwards scan upon reaching the leftmost tuple whose "a"
1713 : : * column has a NULL. The "a" NULL value is ">" 9, and yet
1714 : : * our > row compare will end the scan. (This isn't safe with
1715 : : * later/lower-order row members. Notice that it can only
1716 : : * happen with an "a" NULL some time after the scan completely
1717 : : * stops needing to use its "b" and "c" members.)
1718 : : */
1719 [ - + ]: 32 : if (subkey == (ScanKey) DatumGetPointer(header->sk_argument))
1720 : 0 : reqflags |= SK_BT_REQBKWD; /* safe, first row member */
1721 : :
1722 [ - + - - ]: 32 : if ((subkey->sk_flags & reqflags) &&
1723 : : ScanDirectionIsForward(dir))
1724 : 0 : *continuescan = false;
1725 : : }
1726 : :
1727 : : /*
1728 : : * In any case, this indextuple doesn't match the qual.
1729 : : */
1730 : 32 : return false;
1731 : : }
1732 : :
1733 : : /* Perform the test --- three-way comparison not bool operator */
1734 : 1752 : cmpresult = DatumGetInt32(FunctionCall2Coll(&subkey->sk_func,
1735 : : subkey->sk_collation,
1736 : : datum,
1737 : : subkey->sk_argument));
1738 : :
1739 [ - + ]: 1752 : if (subkey->sk_flags & SK_BT_DESC)
1740 [ # # ]: 0 : INVERT_COMPARE_RESULT(cmpresult);
1741 : :
1742 : : /* Done comparing if unequal, else advance to next column */
1743 [ + + ]: 1752 : if (cmpresult != 0)
1744 : 1592 : break;
1745 : :
1746 [ - + ]: 160 : if (subkey->sk_flags & SK_ROW_END)
1747 : 0 : break;
1748 : 160 : subkey++;
1749 : : }
1750 : :
1751 : : /* Final subkey/column determines if row compare is satisfied */
1752 : 1592 : result = _bt_rowcompare_cmpresult(subkey, cmpresult);
1753 : :
1754 [ + + + - ]: 1592 : if (!result && !forcenonrequired)
1755 : : {
1756 : : /*
1757 : : * Tuple fails this qual. If it's a required qual for the current
1758 : : * scan direction, then we can conclude no further tuples will pass,
1759 : : * either. Note we have to look at the deciding column, not
1760 : : * necessarily the first or last column of the row condition.
1761 : : */
1762 [ + - + - ]: 4 : if ((subkey->sk_flags & SK_BT_REQFWD) &&
1763 : : ScanDirectionIsForward(dir))
1764 : 4 : *continuescan = false;
1765 [ # # # # ]: 0 : else if ((subkey->sk_flags & SK_BT_REQBKWD) &&
1766 : : ScanDirectionIsBackward(dir))
1767 : 0 : *continuescan = false;
1768 : : }
1769 : :
1770 : 1592 : return result;
1771 : : }
1772 : :
1773 : : /*
1774 : : * Call here when a row compare member returns a non-zero result, or with the
1775 : : * result for the final ROW_END row compare member (no matter the cmpresult).
1776 : : *
1777 : : * cmpresult indicates the overall result of the row comparison (must already
1778 : : * be commuted for DESC subkeys), and subkey is the deciding row member.
1779 : : */
1780 : : static bool
1781 : 1592 : _bt_rowcompare_cmpresult(ScanKey subkey, int cmpresult)
1782 : : {
1783 : : bool satisfied;
1784 : :
1785 : : Assert(subkey->sk_flags & SK_ROW_MEMBER);
1786 : :
1787 [ + + + + : 1592 : switch (subkey->sk_strategy)
- ]
1788 : : {
1789 : 124 : case BTLessStrategyNumber:
1790 : 124 : satisfied = (cmpresult < 0);
1791 : 124 : break;
1792 : 1056 : case BTLessEqualStrategyNumber:
1793 : 1056 : satisfied = (cmpresult <= 0);
1794 : 1056 : break;
1795 : 164 : case BTGreaterEqualStrategyNumber:
1796 : 164 : satisfied = (cmpresult >= 0);
1797 : 164 : break;
1798 : 248 : case BTGreaterStrategyNumber:
1799 : 248 : satisfied = (cmpresult > 0);
1800 : 248 : break;
1801 : 0 : default:
1802 : : /* EQ and NE cases aren't allowed here */
1803 [ # # ]: 0 : elog(ERROR, "unexpected strategy number %d", subkey->sk_strategy);
1804 : : satisfied = false; /* keep compiler quiet */
1805 : : break;
1806 : : }
1807 : :
1808 : 1592 : return satisfied;
1809 : : }
1810 : :
1811 : : /*
1812 : : * _bt_tuple_before_array_skeys() -- too early to advance required arrays?
1813 : : *
1814 : : * We always compare the tuple using the current array keys (which we assume
1815 : : * are already set in so->keyData[]). readpagetup indicates if tuple is the
1816 : : * scan's current _bt_readpage-wise tuple.
1817 : : *
1818 : : * readpagetup callers must only call here when _bt_check_compare already set
1819 : : * continuescan=false. We help these callers deal with _bt_check_compare's
1820 : : * inability to distinguish between the < and > cases (it uses equality
1821 : : * operator scan keys, whereas we use 3-way ORDER procs). These callers pass
1822 : : * a _bt_check_compare-set sktrig value that indicates which scan key
1823 : : * triggered the call (!readpagetup callers just pass us sktrig=0 instead).
1824 : : * This information allows us to avoid wastefully checking earlier scan keys
1825 : : * that were already deemed to have been satisfied inside _bt_check_compare.
1826 : : *
1827 : : * Returns false when caller's tuple is >= the current required equality scan
1828 : : * keys (or <=, in the case of backwards scans). This happens to readpagetup
1829 : : * callers when the scan has reached the point of needing its array keys
1830 : : * advanced; caller will need to advance required and non-required arrays at
1831 : : * scan key offsets >= sktrig, plus scan keys < sktrig iff sktrig rolls over.
1832 : : * (When we return false to readpagetup callers, tuple can only be == current
1833 : : * required equality scan keys when caller's sktrig indicates that the arrays
1834 : : * need to be advanced due to an unsatisfied required inequality key trigger.)
1835 : : *
1836 : : * Returns true when caller passes a tuple that is < the current set of
1837 : : * equality keys for the most significant non-equal required scan key/column
1838 : : * (or > the keys, during backwards scans). This happens to readpagetup
1839 : : * callers when tuple is still before the start of matches for the scan's
1840 : : * required equality strategy scan keys. (sktrig can't have indicated that an
1841 : : * inequality strategy scan key wasn't satisfied in _bt_check_compare when we
1842 : : * return true. In fact, we automatically return false when passed such an
1843 : : * inequality sktrig by readpagetup callers -- _bt_check_compare's initial
1844 : : * continuescan=false doesn't really need to be confirmed here by us.)
1845 : : *
1846 : : * !readpagetup callers optionally pass us *scanBehind, which tracks whether
1847 : : * any missing truncated attributes might have affected array advancement
1848 : : * (compared to what would happen if it was shown the first non-pivot tuple on
1849 : : * the page to the right of caller's finaltup/high key tuple instead). It's
1850 : : * only possible that we'll set *scanBehind to true when caller passes us a
1851 : : * pivot tuple (with truncated -inf attributes) that we return false for.
1852 : : */
1853 : : static bool
1854 : 699423 : _bt_tuple_before_array_skeys(IndexScanDesc scan, ScanDirection dir,
1855 : : IndexTuple tuple, TupleDesc tupdesc, int tupnatts,
1856 : : bool readpagetup, int sktrig, bool *scanBehind)
1857 : : {
1858 : 699423 : BTScanOpaque so = (BTScanOpaque) scan->opaque;
1859 : :
1860 : : Assert(so->numArrayKeys);
1861 : : Assert(so->numberOfKeys);
1862 : : Assert(sktrig == 0 || readpagetup);
1863 : : Assert(!readpagetup || scanBehind == NULL);
1864 : :
1865 [ + + ]: 699423 : if (scanBehind)
1866 : 59995 : *scanBehind = false;
1867 : :
1868 [ + + ]: 705635 : for (int ikey = sktrig; ikey < so->numberOfKeys; ikey++)
1869 : : {
1870 : 701331 : ScanKey cur = so->keyData + ikey;
1871 : : Datum tupdatum;
1872 : : bool tupnull;
1873 : : int32 result;
1874 : :
1875 : : /* readpagetup calls require one ORDER proc comparison (at most) */
1876 : : Assert(!readpagetup || ikey == sktrig);
1877 : :
1878 : : /*
1879 : : * Once we reach a non-required scan key, we're completely done.
1880 : : *
1881 : : * Note: we deliberately don't consider the scan direction here.
1882 : : * _bt_advance_array_keys caller requires that we track *scanBehind
1883 : : * without concern for scan direction.
1884 : : */
1885 [ - + ]: 701331 : if ((cur->sk_flags & (SK_BT_REQFWD | SK_BT_REQBKWD)) == 0)
1886 : : {
1887 : : Assert(!readpagetup);
1888 : : Assert(ikey > sktrig || ikey == 0);
1889 : 695119 : return false;
1890 : : }
1891 : :
1892 [ + + ]: 701331 : if (cur->sk_attno > tupnatts)
1893 : : {
1894 : : Assert(!readpagetup);
1895 : :
1896 : : /*
1897 : : * When we reach a high key's truncated attribute, assume that the
1898 : : * tuple attribute's value is >= the scan's equality constraint
1899 : : * scan keys (but set *scanBehind to let interested callers know
1900 : : * that a truncated attribute might have affected our answer).
1901 : : */
1902 [ + - ]: 23 : if (scanBehind)
1903 : 23 : *scanBehind = true;
1904 : :
1905 : 23 : return false;
1906 : : }
1907 : :
1908 : : /*
1909 : : * Deal with inequality strategy scan keys that _bt_check_compare set
1910 : : * continuescan=false for
1911 : : */
1912 [ + + ]: 701308 : if (cur->sk_strategy != BTEqualStrategyNumber)
1913 : : {
1914 : : /*
1915 : : * When _bt_check_compare indicated that a required inequality
1916 : : * scan key wasn't satisfied, there's no need to verify anything;
1917 : : * caller always calls _bt_advance_array_keys with this sktrig.
1918 : : */
1919 [ + + ]: 426 : if (readpagetup)
1920 : 232 : return false;
1921 : :
1922 : : /*
1923 : : * Otherwise we can't give up, since we must check all required
1924 : : * scan keys (required in either direction) in order to correctly
1925 : : * track *scanBehind for caller
1926 : : */
1927 : 194 : continue;
1928 : : }
1929 : :
1930 : 700882 : tupdatum = index_getattr(tuple, cur->sk_attno, tupdesc, &tupnull);
1931 : :
1932 [ + + ]: 700882 : if (likely(!(cur->sk_flags & (SK_BT_MINVAL | SK_BT_MAXVAL))))
1933 : : {
1934 : : /* Scankey has a valid/comparable sk_argument value */
1935 : 697604 : result = _bt_compare_array_skey(&so->orderProcs[ikey],
1936 : : tupdatum, tupnull,
1937 : : cur->sk_argument, cur);
1938 : :
1939 [ + + ]: 697604 : if (result == 0)
1940 : : {
1941 : : /*
1942 : : * Interpret result in a way that takes NEXT/PRIOR into
1943 : : * account
1944 : : */
1945 [ + + ]: 10760 : if (cur->sk_flags & SK_BT_NEXT)
1946 : 4722 : result = -1;
1947 [ + + ]: 6038 : else if (cur->sk_flags & SK_BT_PRIOR)
1948 : 20 : result = 1;
1949 : :
1950 : : Assert(result == 0 || (cur->sk_flags & SK_BT_SKIP));
1951 : : }
1952 : : }
1953 : : else
1954 : : {
1955 : 3278 : BTArrayKeyInfo *array = NULL;
1956 : :
1957 : : /*
1958 : : * Current array element/array = scan key value is a sentinel
1959 : : * value that represents the lowest (or highest) possible value
1960 : : * that's still within the range of the array.
1961 : : *
1962 : : * Like _bt_first, we only see MINVAL keys during forwards scans
1963 : : * (and similarly only see MAXVAL keys during backwards scans).
1964 : : * Even if the scan's direction changes, we'll stop at some higher
1965 : : * order key before we can ever reach any MAXVAL (or MINVAL) keys.
1966 : : * (However, unlike _bt_first we _can_ get to keys marked either
1967 : : * NEXT or PRIOR, regardless of the scan's current direction.)
1968 : : */
1969 : : Assert(ScanDirectionIsForward(dir) ?
1970 : : !(cur->sk_flags & SK_BT_MAXVAL) :
1971 : : !(cur->sk_flags & SK_BT_MINVAL));
1972 : :
1973 : : /*
1974 : : * There are no valid sk_argument values in MINVAL/MAXVAL keys.
1975 : : * Check if tupdatum is within the range of skip array instead.
1976 : : */
1977 [ + - ]: 3552 : for (int arrayidx = 0; arrayidx < so->numArrayKeys; arrayidx++)
1978 : : {
1979 : 3552 : array = &so->arrayKeys[arrayidx];
1980 [ + + ]: 3552 : if (array->scan_key == ikey)
1981 : 3278 : break;
1982 : : }
1983 : :
1984 : 3278 : _bt_binsrch_skiparray_skey(false, dir, tupdatum, tupnull,
1985 : : array, cur, &result);
1986 : :
1987 [ + + ]: 3278 : if (result == 0)
1988 : : {
1989 : : /*
1990 : : * tupdatum satisfies both low_compare and high_compare, so
1991 : : * it's time to advance the array keys.
1992 : : *
1993 : : * Note: It's possible that the skip array will "advance" from
1994 : : * its MINVAL (or MAXVAL) representation to an alternative,
1995 : : * logically equivalent representation of the same value: a
1996 : : * representation where the = key gets a valid datum in its
1997 : : * sk_argument. This is only possible when low_compare uses
1998 : : * the >= strategy (or high_compare uses the <= strategy).
1999 : : */
2000 : 3271 : return false;
2001 : : }
2002 : : }
2003 : :
2004 : : /*
2005 : : * Does this comparison indicate that caller must _not_ advance the
2006 : : * scan's arrays just yet?
2007 : : */
2008 [ + + + + : 697611 : if ((ScanDirectionIsForward(dir) && result < 0) ||
+ + ]
2009 [ + + ]: 2168 : (ScanDirectionIsBackward(dir) && result > 0))
2010 : 108599 : return true;
2011 : :
2012 : : /*
2013 : : * Does this comparison indicate that caller should now advance the
2014 : : * scan's arrays? (Must be if we get here during a readpagetup call.)
2015 : : */
2016 [ + + + + ]: 589012 : if (readpagetup || result != 0)
2017 : : {
2018 : : Assert(result != 0);
2019 : 582994 : return false;
2020 : : }
2021 : :
2022 : : /*
2023 : : * Inconclusive -- need to check later scan keys, too.
2024 : : *
2025 : : * This must be a finaltup precheck, or a call made from an assertion.
2026 : : */
2027 : : Assert(result == 0);
2028 : : }
2029 : :
2030 : : Assert(!readpagetup);
2031 : :
2032 : 4304 : return false;
2033 : : }
2034 : :
2035 : : /*
2036 : : * Determine if a scan with array keys should skip over uninteresting tuples.
2037 : : *
2038 : : * This is a subroutine for _bt_checkkeys, called when _bt_readpage's linear
2039 : : * search process has scanned an excessive number of tuples whose key space is
2040 : : * "between arrays". (The linear search process is started after _bt_readpage
2041 : : * finishes reading an initial group of matching tuples. It locates the start
2042 : : * of the first group of tuples matching the next set of required array keys.)
2043 : : *
2044 : : * When look ahead is successful, we set pstate.skip which
2045 : : * instructs _bt_readpage to skip ahead to that tuple next (could be past the
2046 : : * end of the scan's leaf page). Pages where the optimization is effective
2047 : : * will generally still need to skip several times. Each call here performs
2048 : : * only a single "look ahead" comparison of a later tuple, whose distance from
2049 : : * the current tuple is determined by heuristics.
2050 : : */
2051 : : static void
2052 : 34488 : _bt_checkkeys_look_ahead(IndexScanDesc scan, BTReadPageState *pstate,
2053 : : int tupnatts, TupleDesc tupdesc)
2054 : : {
2055 : 34488 : ScanDirection dir = pstate->dir;
2056 : : OffsetNumber aheadoffnum;
2057 : : IndexTuple ahead;
2058 : :
2059 : : Assert(!pstate->forcenonrequired);
2060 : :
2061 : : /* Avoid looking ahead when comparing the page high key */
2062 [ - + ]: 34488 : if (pstate->offnum < pstate->minoff)
2063 : 0 : return;
2064 : :
2065 : : /*
2066 : : * Don't look ahead when there aren't enough tuples remaining on the page
2067 : : * (in the current scan direction) for it to be worth our while
2068 : : */
2069 [ + + ]: 34488 : if (ScanDirectionIsForward(dir) &&
2070 [ + + ]: 34436 : pstate->offnum >= pstate->maxoff - LOOK_AHEAD_DEFAULT_DISTANCE)
2071 : 540 : return;
2072 [ + + ]: 33948 : else if (ScanDirectionIsBackward(dir) &&
2073 [ + + ]: 52 : pstate->offnum <= pstate->minoff + LOOK_AHEAD_DEFAULT_DISTANCE)
2074 : 16 : return;
2075 : :
2076 : : /*
2077 : : * The look ahead distance starts small, and ramps up as each call here
2078 : : * allows _bt_readpage to skip over more tuples
2079 : : */
2080 [ + + ]: 33932 : if (!pstate->targetdistance)
2081 : 7147 : pstate->targetdistance = LOOK_AHEAD_DEFAULT_DISTANCE;
2082 [ + - ]: 26785 : else if (pstate->targetdistance < MaxIndexTuplesPerPage / 2)
2083 : 26785 : pstate->targetdistance *= 2;
2084 : :
2085 : : /* Don't read past the end (or before the start) of the page, though */
2086 [ + + ]: 33932 : if (ScanDirectionIsForward(dir))
2087 : 33896 : aheadoffnum = Min((int) pstate->maxoff,
2088 : : (int) pstate->offnum + pstate->targetdistance);
2089 : : else
2090 : 36 : aheadoffnum = Max((int) pstate->minoff,
2091 : : (int) pstate->offnum - pstate->targetdistance);
2092 : :
2093 : 33932 : ahead = (IndexTuple) PageGetItem(pstate->page,
2094 : 33932 : PageGetItemId(pstate->page, aheadoffnum));
2095 [ + + ]: 33932 : if (_bt_tuple_before_array_skeys(scan, dir, ahead, tupdesc, tupnatts,
2096 : : false, 0, NULL))
2097 : : {
2098 : : /*
2099 : : * Success -- instruct _bt_readpage to skip ahead to very next tuple
2100 : : * after the one we determined was still before the current array keys
2101 : : */
2102 [ + + ]: 18414 : if (ScanDirectionIsForward(dir))
2103 : 18390 : pstate->skip = aheadoffnum + 1;
2104 : : else
2105 : 24 : pstate->skip = aheadoffnum - 1;
2106 : : }
2107 : : else
2108 : : {
2109 : : /*
2110 : : * Failure -- "ahead" tuple is too far ahead (we were too aggressive).
2111 : : *
2112 : : * Reset the number of rechecks, and aggressively reduce the target
2113 : : * distance (we're much more aggressive here than we were when the
2114 : : * distance was initially ramped up).
2115 : : */
2116 : 15518 : pstate->rechecks = 0;
2117 [ + + ]: 15518 : pstate->targetdistance = Max(pstate->targetdistance / 8, 1);
2118 : : }
2119 : : }
2120 : :
2121 : : /*
2122 : : * _bt_advance_array_keys() -- Advance array elements using a tuple
2123 : : *
2124 : : * The scan always gets a new qual as a consequence of calling here (except
2125 : : * when we determine that the top-level scan has run out of matching tuples).
2126 : : * All later _bt_check_compare calls also use the same new qual that was first
2127 : : * used here (at least until the next call here advances the keys once again).
2128 : : * It's convenient to structure _bt_check_compare rechecks of caller's tuple
2129 : : * (using the new qual) as one the steps of advancing the scan's array keys,
2130 : : * so this function works as a wrapper around _bt_check_compare.
2131 : : *
2132 : : * Like _bt_check_compare, we'll set pstate.continuescan on behalf of the
2133 : : * caller, and return a boolean indicating if caller's tuple satisfies the
2134 : : * scan's new qual. But unlike _bt_check_compare, we set so->needPrimScan
2135 : : * when we set continuescan=false, indicating if a new primitive index scan
2136 : : * has been scheduled (otherwise, the top-level scan has run out of tuples in
2137 : : * the current scan direction).
2138 : : *
2139 : : * Caller must use _bt_tuple_before_array_skeys to determine if the current
2140 : : * place in the scan is >= the current array keys _before_ calling here.
2141 : : * We're responsible for ensuring that caller's tuple is <= the newly advanced
2142 : : * required array keys once we return. We try to find an exact match, but
2143 : : * failing that we'll advance the array keys to whatever set of array elements
2144 : : * comes next in the key space for the current scan direction. Required array
2145 : : * keys "ratchet forwards" (or backwards). They can only advance as the scan
2146 : : * itself advances through the index/key space.
2147 : : *
2148 : : * (The rules are the same for backwards scans, except that the operators are
2149 : : * flipped: just replace the precondition's >= operator with a <=, and the
2150 : : * postcondition's <= operator with a >=. In other words, just swap the
2151 : : * precondition with the postcondition.)
2152 : : *
2153 : : * We also deal with "advancing" non-required arrays here (or arrays that are
2154 : : * treated as non-required for the duration of a _bt_readpage call). Callers
2155 : : * whose sktrig scan key is non-required specify sktrig_required=false. These
2156 : : * calls are the only exception to the general rule about always advancing the
2157 : : * required array keys (the scan may not even have a required array). These
2158 : : * callers should just pass a NULL pstate (since there is never any question
2159 : : * of stopping the scan). No call to _bt_tuple_before_array_skeys is required
2160 : : * ahead of these calls (it's already clear that any required scan keys must
2161 : : * be satisfied by caller's tuple).
2162 : : *
2163 : : * Note that we deal with non-array required equality strategy scan keys as
2164 : : * degenerate single element arrays here. Obviously, they can never really
2165 : : * advance in the way that real arrays can, but they must still affect how we
2166 : : * advance real array scan keys (exactly like true array equality scan keys).
2167 : : * We have to keep around a 3-way ORDER proc for these (using the "=" operator
2168 : : * won't do), since in general whether the tuple is < or > _any_ unsatisfied
2169 : : * required equality key influences how the scan's real arrays must advance.
2170 : : *
2171 : : * Note also that we may sometimes need to advance the array keys when the
2172 : : * existing required array keys (and other required equality keys) are already
2173 : : * an exact match for every corresponding value from caller's tuple. We must
2174 : : * do this for inequalities that _bt_check_compare set continuescan=false for.
2175 : : * They'll advance the array keys here, just like any other scan key that
2176 : : * _bt_check_compare stops on. (This can even happen _after_ we advance the
2177 : : * array keys, in which case we'll advance the array keys a second time. That
2178 : : * way _bt_checkkeys caller always has its required arrays advance to the
2179 : : * maximum possible extent that its tuple will allow.)
2180 : : */
2181 : : static bool
2182 : 533399 : _bt_advance_array_keys(IndexScanDesc scan, BTReadPageState *pstate,
2183 : : IndexTuple tuple, int tupnatts, TupleDesc tupdesc,
2184 : : int sktrig, bool sktrig_required)
2185 : : {
2186 : 533399 : BTScanOpaque so = (BTScanOpaque) scan->opaque;
2187 : 533399 : Relation rel = scan->indexRelation;
2188 [ + + ]: 533399 : ScanDirection dir = pstate ? pstate->dir : ForwardScanDirection;
2189 : 533399 : int arrayidx = 0;
2190 : 533399 : bool beyond_end_advance = false,
2191 : 533399 : skip_array_advanced = false,
2192 : 533399 : has_required_opposite_direction_only = false,
2193 : 533399 : all_required_satisfied = true,
2194 : 533399 : all_satisfied = true;
2195 : :
2196 : : Assert(!so->needPrimScan && !so->scanBehind && !so->oppositeDirCheck);
2197 : : Assert(_bt_verify_keys_with_arraykeys(scan));
2198 : :
2199 [ + + ]: 533399 : if (sktrig_required)
2200 : : {
2201 : : /*
2202 : : * Precondition array state assertion
2203 : : */
2204 : : Assert(!_bt_tuple_before_array_skeys(scan, dir, tuple, tupdesc,
2205 : : tupnatts, false, 0, NULL));
2206 : :
2207 : : /*
2208 : : * Once we return we'll have a new set of required array keys, so
2209 : : * reset state used by "look ahead" optimization
2210 : : */
2211 : 527368 : pstate->rechecks = 0;
2212 : 527368 : pstate->targetdistance = 0;
2213 : : }
2214 [ + - ]: 6031 : else if (sktrig < so->numberOfKeys - 1 &&
2215 [ + - ]: 6031 : !(so->keyData[so->numberOfKeys - 1].sk_flags & SK_SEARCHARRAY))
2216 : : {
2217 : 6031 : int least_sign_ikey = so->numberOfKeys - 1;
2218 : : bool continuescan;
2219 : :
2220 : : /*
2221 : : * Optimization: perform a precheck of the least significant key
2222 : : * during !sktrig_required calls when it isn't already our sktrig
2223 : : * (provided the precheck key is not itself an array).
2224 : : *
2225 : : * When the precheck works out we'll avoid an expensive binary search
2226 : : * of sktrig's array (plus any other arrays before least_sign_ikey).
2227 : : */
2228 : : Assert(so->keyData[sktrig].sk_flags & SK_SEARCHARRAY);
2229 [ + + ]: 6031 : if (!_bt_check_compare(scan, dir, tuple, tupnatts, tupdesc, false,
2230 : : false, &continuescan,
2231 : : &least_sign_ikey))
2232 : 1839 : return false;
2233 : : }
2234 : :
2235 [ + + ]: 1178909 : for (int ikey = 0; ikey < so->numberOfKeys; ikey++)
2236 : : {
2237 : 651193 : ScanKey cur = so->keyData + ikey;
2238 : 651193 : BTArrayKeyInfo *array = NULL;
2239 : : Datum tupdatum;
2240 : 651193 : bool required = false,
2241 : : tupnull;
2242 : : int32 result;
2243 : 651193 : int set_elem = 0;
2244 : :
2245 [ + + ]: 651193 : if (cur->sk_strategy == BTEqualStrategyNumber)
2246 : : {
2247 : : /* Manage array state */
2248 [ + + ]: 619106 : if (cur->sk_flags & SK_SEARCHARRAY)
2249 : : {
2250 : 538914 : array = &so->arrayKeys[arrayidx++];
2251 : : Assert(array->scan_key == ikey);
2252 : : }
2253 : : }
2254 : : else
2255 : : {
2256 : : /*
2257 : : * Are any inequalities required in the opposite direction only
2258 : : * present here?
2259 : : */
2260 [ + - ]: 32087 : if (((ScanDirectionIsForward(dir) &&
2261 [ + + - + ]: 32087 : (cur->sk_flags & (SK_BT_REQBKWD))) ||
2262 : 0 : (ScanDirectionIsBackward(dir) &&
2263 [ # # ]: 0 : (cur->sk_flags & (SK_BT_REQFWD)))))
2264 : 10391 : has_required_opposite_direction_only = true;
2265 : : }
2266 : :
2267 : : /* Optimization: skip over known-satisfied scan keys */
2268 [ + + ]: 651193 : if (ikey < sktrig)
2269 : 50475 : continue;
2270 : :
2271 [ + - ]: 640555 : if (cur->sk_flags & (SK_BT_REQFWD | SK_BT_REQBKWD))
2272 : : {
2273 : 640555 : required = true;
2274 : :
2275 [ + + ]: 640555 : if (cur->sk_attno > tupnatts)
2276 : : {
2277 : : /* Set this just like _bt_tuple_before_array_skeys */
2278 : : Assert(sktrig < ikey);
2279 : 1710 : so->scanBehind = true;
2280 : : }
2281 : : }
2282 : :
2283 : : /*
2284 : : * Handle a required non-array scan key that the initial call to
2285 : : * _bt_check_compare indicated triggered array advancement, if any.
2286 : : *
2287 : : * The non-array scan key's strategy will be <, <=, or = during a
2288 : : * forwards scan (or any one of =, >=, or > during a backwards scan).
2289 : : * It follows that the corresponding tuple attribute's value must now
2290 : : * be either > or >= the scan key value (for backwards scans it must
2291 : : * be either < or <= that value).
2292 : : *
2293 : : * If this is a required equality strategy scan key, this is just an
2294 : : * optimization; _bt_tuple_before_array_skeys already confirmed that
2295 : : * this scan key places us ahead of caller's tuple. There's no need
2296 : : * to repeat that work now. (The same underlying principle also gets
2297 : : * applied by the cur_elem_trig optimization used to speed up searches
2298 : : * for the next array element.)
2299 : : *
2300 : : * If this is a required inequality strategy scan key, we _must_ rely
2301 : : * on _bt_check_compare like this; we aren't capable of directly
2302 : : * evaluating required inequality strategy scan keys here, on our own.
2303 : : */
2304 [ + + + + ]: 640555 : if (ikey == sktrig && !array)
2305 : : {
2306 : : Assert(sktrig_required && required && all_required_satisfied);
2307 : :
2308 : : /* Use "beyond end" advancement. See below for an explanation. */
2309 : 4658 : beyond_end_advance = true;
2310 : 4658 : all_satisfied = all_required_satisfied = false;
2311 : :
2312 : 4658 : continue;
2313 : : }
2314 : :
2315 : : /*
2316 : : * Nothing more for us to do with an inequality strategy scan key that
2317 : : * wasn't the one that _bt_check_compare stopped on, though.
2318 : : *
2319 : : * Note: if our later call to _bt_check_compare (to recheck caller's
2320 : : * tuple) sets continuescan=false due to finding this same inequality
2321 : : * unsatisfied (possible when it's required in the scan direction),
2322 : : * we'll deal with it via a recursive "second pass" call.
2323 : : */
2324 [ + + ]: 635897 : else if (cur->sk_strategy != BTEqualStrategyNumber)
2325 : 31707 : continue;
2326 : :
2327 : : /*
2328 : : * Nothing for us to do with an equality strategy scan key that isn't
2329 : : * marked required, either -- unless it's a non-required array
2330 : : */
2331 [ - + - - ]: 604190 : else if (!required && !array)
2332 : 0 : continue;
2333 : :
2334 : : /*
2335 : : * Here we perform steps for all array scan keys after a required
2336 : : * array scan key whose binary search triggered "beyond end of array
2337 : : * element" array advancement due to encountering a tuple attribute
2338 : : * value > the closest matching array key (or < for backwards scans).
2339 : : */
2340 [ + + ]: 604190 : if (beyond_end_advance)
2341 : : {
2342 [ + + ]: 1172 : if (array)
2343 : 681 : _bt_array_set_low_or_high(rel, cur, array,
2344 : : ScanDirectionIsBackward(dir));
2345 : :
2346 : 1172 : continue;
2347 : : }
2348 : :
2349 : : /*
2350 : : * Here we perform steps for all array scan keys after a required
2351 : : * array scan key whose tuple attribute was < the closest matching
2352 : : * array key when we dealt with it (or > for backwards scans).
2353 : : *
2354 : : * This earlier required array key already puts us ahead of caller's
2355 : : * tuple in the key space (for the current scan direction). We must
2356 : : * make sure that subsequent lower-order array keys do not put us too
2357 : : * far ahead (ahead of tuples that have yet to be seen by our caller).
2358 : : * For example, when a tuple "(a, b) = (42, 5)" advances the array
2359 : : * keys on "a" from 40 to 45, we must also set "b" to whatever the
2360 : : * first array element for "b" is. It would be wrong to allow "b" to
2361 : : * be set based on the tuple value.
2362 : : *
2363 : : * Perform the same steps with truncated high key attributes. You can
2364 : : * think of this as a "binary search" for the element closest to the
2365 : : * value -inf. Again, the arrays must never get ahead of the scan.
2366 : : */
2367 [ + + + + ]: 603018 : if (!all_required_satisfied || cur->sk_attno > tupnatts)
2368 : : {
2369 [ + + ]: 2300 : if (array)
2370 : 464 : _bt_array_set_low_or_high(rel, cur, array,
2371 : : ScanDirectionIsForward(dir));
2372 : :
2373 : 2300 : continue;
2374 : : }
2375 : :
2376 : : /*
2377 : : * Search in scankey's array for the corresponding tuple attribute
2378 : : * value from caller's tuple
2379 : : */
2380 : 600718 : tupdatum = index_getattr(tuple, cur->sk_attno, tupdesc, &tupnull);
2381 : :
2382 [ + + ]: 600718 : if (array)
2383 : : {
2384 [ + + + + ]: 528231 : bool cur_elem_trig = (sktrig_required && ikey == sktrig);
2385 : :
2386 : : /*
2387 : : * "Binary search" by checking if tupdatum/tupnull are within the
2388 : : * range of the skip array
2389 : : */
2390 [ + + ]: 528231 : if (array->num_elems == -1)
2391 : 99633 : _bt_binsrch_skiparray_skey(cur_elem_trig, dir,
2392 : : tupdatum, tupnull, array, cur,
2393 : : &result);
2394 : :
2395 : : /*
2396 : : * Binary search for the closest match from the SAOP array
2397 : : */
2398 : : else
2399 : 428598 : set_elem = _bt_binsrch_array_skey(&so->orderProcs[ikey],
2400 : : cur_elem_trig, dir,
2401 : : tupdatum, tupnull, array, cur,
2402 : : &result);
2403 : : }
2404 : : else
2405 : : {
2406 : : Assert(required);
2407 : :
2408 : : /*
2409 : : * This is a required non-array equality strategy scan key, which
2410 : : * we'll treat as a degenerate single element array.
2411 : : *
2412 : : * This scan key's imaginary "array" can't really advance, but it
2413 : : * can still roll over like any other array. (Actually, this is
2414 : : * no different to real single value arrays, which never advance
2415 : : * without rolling over -- they can never truly advance, either.)
2416 : : */
2417 : 72487 : result = _bt_compare_array_skey(&so->orderProcs[ikey],
2418 : : tupdatum, tupnull,
2419 : : cur->sk_argument, cur);
2420 : : }
2421 : :
2422 : : /*
2423 : : * Consider "beyond end of array element" array advancement.
2424 : : *
2425 : : * When the tuple attribute value is > the closest matching array key
2426 : : * (or < in the backwards scan case), we need to ratchet this array
2427 : : * forward (backward) by one increment, so that caller's tuple ends up
2428 : : * being < final array value instead (or > final array value instead).
2429 : : * This process has to work for all of the arrays, not just this one:
2430 : : * it must "carry" to higher-order arrays when the set_elem that we
2431 : : * just found happens to be the final one for the scan's direction.
2432 : : * Incrementing (decrementing) set_elem itself isn't good enough.
2433 : : *
2434 : : * Our approach is to provisionally use set_elem as if it was an exact
2435 : : * match now, then set each later/less significant array to whatever
2436 : : * its final element is. Once outside the loop we'll then "increment
2437 : : * this array's set_elem" by calling _bt_advance_array_keys_increment.
2438 : : * That way the process rolls over to higher order arrays as needed.
2439 : : *
2440 : : * Under this scheme any required arrays only ever ratchet forwards
2441 : : * (or backwards), and always do so to the maximum possible extent
2442 : : * that we can know will be safe without seeing the scan's next tuple.
2443 : : * We don't need any special handling for required scan keys that lack
2444 : : * a real array to advance, nor for redundant scan keys that couldn't
2445 : : * be eliminated by _bt_preprocess_keys. It won't matter if some of
2446 : : * our "true" array scan keys (or even all of them) are non-required.
2447 : : */
2448 [ + + + - : 600718 : if (sktrig_required && required &&
+ + ]
2449 [ + + + + ]: 596526 : ((ScanDirectionIsForward(dir) && result > 0) ||
2450 [ + + ]: 1144 : (ScanDirectionIsBackward(dir) && result < 0)))
2451 : 22871 : beyond_end_advance = true;
2452 : :
2453 : : Assert(all_required_satisfied && all_satisfied);
2454 [ + + ]: 600718 : if (result != 0)
2455 : : {
2456 : : /*
2457 : : * Track whether caller's tuple satisfies our new post-advancement
2458 : : * qual, for required scan keys, as well as for the entire set of
2459 : : * interesting scan keys (all required scan keys plus non-required
2460 : : * array scan keys are considered interesting.)
2461 : : */
2462 : 100124 : all_satisfied = false;
2463 [ + + + - ]: 100124 : if (sktrig_required && required)
2464 : 96280 : all_required_satisfied = false;
2465 : : else
2466 : : {
2467 : : /*
2468 : : * There's no need to advance the arrays using the best
2469 : : * available match for a non-required array. Give up now.
2470 : : * (Though note that sktrig_required calls still have to do
2471 : : * all the usual post-advancement steps, including the recheck
2472 : : * call to _bt_check_compare.)
2473 : : */
2474 : : break;
2475 : : }
2476 : : }
2477 : :
2478 : : /* Advance array keys, even when we don't have an exact match */
2479 [ + + ]: 596874 : if (array)
2480 : : {
2481 [ + + ]: 524387 : if (array->num_elems == -1)
2482 : : {
2483 : : /* Skip array's new element is tupdatum (or MINVAL/MAXVAL) */
2484 : 95789 : _bt_skiparray_set_element(rel, cur, array, result,
2485 : : tupdatum, tupnull);
2486 : 95789 : skip_array_advanced = true;
2487 : : }
2488 [ + + ]: 428598 : else if (array->cur_elem != set_elem)
2489 : : {
2490 : : /* SAOP array's new element is set_elem datum */
2491 : 415873 : array->cur_elem = set_elem;
2492 : 415873 : cur->sk_argument = array->elem_values[set_elem];
2493 : : }
2494 : : }
2495 : : }
2496 : :
2497 : : /*
2498 : : * Advance the array keys incrementally whenever "beyond end of array
2499 : : * element" array advancement happens, so that advancement will carry to
2500 : : * higher-order arrays (might exhaust all the scan's arrays instead, which
2501 : : * ends the top-level scan).
2502 : : */
2503 [ + + ]: 531560 : if (beyond_end_advance &&
2504 [ + + ]: 27529 : !_bt_advance_array_keys_increment(scan, dir, &skip_array_advanced))
2505 : 12962 : goto end_toplevel_scan;
2506 : :
2507 : : Assert(_bt_verify_keys_with_arraykeys(scan));
2508 : :
2509 : : /*
2510 : : * Maintain a page-level count of the number of times the scan's array
2511 : : * keys advanced in a way that affected at least one skip array
2512 : : */
2513 [ + + + + ]: 518598 : if (sktrig_required && skip_array_advanced)
2514 : 99086 : pstate->nskipadvances++;
2515 : :
2516 : : /*
2517 : : * Does tuple now satisfy our new qual? Recheck with _bt_check_compare.
2518 : : *
2519 : : * Calls triggered by an unsatisfied required scan key, whose tuple now
2520 : : * satisfies all required scan keys, but not all nonrequired array keys,
2521 : : * will still require a recheck call to _bt_check_compare. They'll still
2522 : : * need its "second pass" handling of required inequality scan keys.
2523 : : * (Might have missed a still-unsatisfied required inequality scan key
2524 : : * that caller didn't detect as the sktrig scan key during its initial
2525 : : * _bt_check_compare call that used the old/original qual.)
2526 : : *
2527 : : * Calls triggered by an unsatisfied nonrequired array scan key never need
2528 : : * "second pass" handling of required inequalities (nor any other handling
2529 : : * of any required scan key). All that matters is whether caller's tuple
2530 : : * satisfies the new qual, so it's safe to just skip the _bt_check_compare
2531 : : * recheck when we've already determined that it can only return 'false'.
2532 : : *
2533 : : * Note: In practice most scan keys are marked required by preprocessing,
2534 : : * if necessary by generating a preceding skip array. We nevertheless
2535 : : * often handle array keys marked required as if they were nonrequired.
2536 : : * This behavior is requested by our _bt_check_compare caller, though only
2537 : : * when it is passed "forcenonrequired=true" by _bt_checkkeys.
2538 : : */
2539 [ + + + + ]: 518598 : if ((sktrig_required && all_required_satisfied) ||
2540 [ + + + + ]: 92168 : (!sktrig_required && all_satisfied))
2541 : : {
2542 : 426778 : int nsktrig = sktrig + 1;
2543 : : bool continuescan;
2544 : :
2545 : : Assert(all_required_satisfied);
2546 : :
2547 : : /* Recheck _bt_check_compare on behalf of caller */
2548 [ + + ]: 426778 : if (_bt_check_compare(scan, dir, tuple, tupnatts, tupdesc, false,
2549 : : !sktrig_required, &continuescan,
2550 : 426778 : &nsktrig) &&
2551 [ + + ]: 421668 : !so->scanBehind)
2552 : : {
2553 : : /* This tuple satisfies the new qual */
2554 : : Assert(all_satisfied && continuescan);
2555 : :
2556 [ + + ]: 420029 : if (pstate)
2557 : 419681 : pstate->continuescan = true;
2558 : :
2559 : 420177 : return true;
2560 : : }
2561 : :
2562 : : /*
2563 : : * Consider "second pass" handling of required inequalities.
2564 : : *
2565 : : * It's possible that our _bt_check_compare call indicated that the
2566 : : * scan should end due to some unsatisfied inequality that wasn't
2567 : : * initially recognized as such by us. Handle this by calling
2568 : : * ourselves recursively, this time indicating that the trigger is the
2569 : : * inequality that we missed first time around (and using a set of
2570 : : * required array/equality keys that are now exact matches for tuple).
2571 : : *
2572 : : * We make a strong, general guarantee that every _bt_checkkeys call
2573 : : * here will advance the array keys to the maximum possible extent
2574 : : * that we can know to be safe based on caller's tuple alone. If we
2575 : : * didn't perform this step, then that guarantee wouldn't quite hold.
2576 : : */
2577 [ + + ]: 6749 : if (unlikely(!continuescan))
2578 : : {
2579 : : bool satisfied PG_USED_FOR_ASSERTS_ONLY;
2580 : :
2581 : : Assert(sktrig_required);
2582 : : Assert(so->keyData[nsktrig].sk_strategy != BTEqualStrategyNumber);
2583 : :
2584 : : /*
2585 : : * The tuple must use "beyond end" advancement during the
2586 : : * recursive call, so we cannot possibly end up back here when
2587 : : * recursing. We'll consume a small, fixed amount of stack space.
2588 : : */
2589 : : Assert(!beyond_end_advance);
2590 : :
2591 : : /* Advance the array keys a second time using same tuple */
2592 : 148 : satisfied = _bt_advance_array_keys(scan, pstate, tuple, tupnatts,
2593 : : tupdesc, nsktrig, true);
2594 : :
2595 : : /* This tuple doesn't satisfy the inequality */
2596 : : Assert(!satisfied);
2597 : 148 : return false;
2598 : : }
2599 : :
2600 : : /*
2601 : : * Some non-required scan key (from new qual) still not satisfied.
2602 : : *
2603 : : * All scan keys required in the current scan direction must still be
2604 : : * satisfied, though, so we can trust all_required_satisfied below.
2605 : : */
2606 : : }
2607 : :
2608 : : /*
2609 : : * When we were called just to deal with "advancing" non-required arrays,
2610 : : * this is as far as we can go (cannot stop the scan for these callers)
2611 : : */
2612 [ + + ]: 98421 : if (!sktrig_required)
2613 : : {
2614 : : /* Caller's tuple doesn't match any qual */
2615 : 3844 : return false;
2616 : : }
2617 : :
2618 : : /*
2619 : : * Postcondition array state assertion (for still-unsatisfied tuples).
2620 : : *
2621 : : * By here we have established that the scan's required arrays (scan must
2622 : : * have at least one required array) advanced, without becoming exhausted.
2623 : : *
2624 : : * Caller's tuple is now < the newly advanced array keys (or > when this
2625 : : * is a backwards scan), except in the case where we only got this far due
2626 : : * to an unsatisfied non-required scan key. Verify that with an assert.
2627 : : *
2628 : : * Note: we don't just quit at this point when all required scan keys were
2629 : : * found to be satisfied because we need to consider edge-cases involving
2630 : : * scan keys required in the opposite direction only; those aren't tracked
2631 : : * by all_required_satisfied.
2632 : : */
2633 : : Assert(_bt_tuple_before_array_skeys(scan, dir, tuple, tupdesc, tupnatts,
2634 : : false, 0, NULL) ==
2635 : : !all_required_satisfied);
2636 : :
2637 : : /*
2638 : : * We generally permit primitive index scans to continue onto the next
2639 : : * sibling page when the page's finaltup satisfies all required scan keys
2640 : : * at the point where we're between pages.
2641 : : *
2642 : : * If caller's tuple is also the page's finaltup, and we see that required
2643 : : * scan keys still aren't satisfied, start a new primitive index scan.
2644 : : */
2645 [ + + + + ]: 94577 : if (!all_required_satisfied && pstate->finaltup == tuple)
2646 : 468 : goto new_prim_scan;
2647 : :
2648 : : /*
2649 : : * Proactively check finaltup (don't wait until finaltup is reached by the
2650 : : * scan) when it might well turn out to not be satisfied later on.
2651 : : *
2652 : : * Note: if so->scanBehind hasn't already been set for finaltup by us,
2653 : : * it'll be set during this call to _bt_tuple_before_array_skeys. Either
2654 : : * way, it'll be set correctly (for the whole page) after this point.
2655 : : */
2656 [ + + + + : 152186 : if (!all_required_satisfied && pstate->finaltup &&
+ + ]
2657 [ + + ]: 116154 : _bt_tuple_before_array_skeys(scan, dir, pstate->finaltup, tupdesc,
2658 : 116154 : BTreeTupleGetNAtts(pstate->finaltup, rel),
2659 : : false, 0, &so->scanBehind))
2660 : 11629 : goto new_prim_scan;
2661 : :
2662 : : /*
2663 : : * When we encounter a truncated finaltup high key attribute, we're
2664 : : * optimistic about the chances of its corresponding required scan key
2665 : : * being satisfied when we go on to recheck it against tuples from this
2666 : : * page's right sibling leaf page. We consider truncated attributes to be
2667 : : * satisfied by required scan keys, which allows the primitive index scan
2668 : : * to continue to the next leaf page. We must set so->scanBehind to true
2669 : : * to remember that the last page's finaltup had "satisfied" required scan
2670 : : * keys for one or more truncated attribute values (scan keys required in
2671 : : * _either_ scan direction).
2672 : : *
2673 : : * There is a chance that _bt_readpage (which checks so->scanBehind) will
2674 : : * find that even the sibling leaf page's finaltup is < the new array
2675 : : * keys. When that happens, our optimistic policy will have incurred a
2676 : : * single extra leaf page access that could have been avoided.
2677 : : *
2678 : : * A pessimistic policy would give backward scans a gratuitous advantage
2679 : : * over forward scans. We'd punish forward scans for applying more
2680 : : * accurate information from the high key, rather than just using the
2681 : : * final non-pivot tuple as finaltup, in the style of backward scans.
2682 : : * Being pessimistic would also give some scans with non-required arrays a
2683 : : * perverse advantage over similar scans that use required arrays instead.
2684 : : *
2685 : : * This is similar to our scan-level heuristics, below. They also set
2686 : : * scanBehind to speculatively continue the primscan onto the next page.
2687 : : */
2688 [ + + ]: 82480 : if (so->scanBehind)
2689 : : {
2690 : : /* Truncated high key -- _bt_scanbehind_checkkeys recheck scheduled */
2691 : : }
2692 : :
2693 : : /*
2694 : : * Handle inequalities marked required in the opposite scan direction.
2695 : : * They can also signal that we should start a new primitive index scan.
2696 : : *
2697 : : * It's possible that the scan is now positioned where "matching" tuples
2698 : : * begin, and that caller's tuple satisfies all scan keys required in the
2699 : : * current scan direction. But if caller's tuple still doesn't satisfy
2700 : : * other scan keys that are required in the opposite scan direction only
2701 : : * (e.g., a required >= strategy scan key when scan direction is forward),
2702 : : * it's still possible that there are many leaf pages before the page that
2703 : : * _bt_first could skip straight to. Groveling through all those pages
2704 : : * will always give correct answers, but it can be very inefficient. We
2705 : : * must avoid needlessly scanning extra pages.
2706 : : *
2707 : : * Separately, it's possible that _bt_check_compare set continuescan=false
2708 : : * for a scan key that's required in the opposite direction only. This is
2709 : : * a special case, that happens only when _bt_check_compare sees that the
2710 : : * inequality encountered a NULL value. This signals the end of non-NULL
2711 : : * values in the current scan direction, which is reason enough to end the
2712 : : * (primitive) scan. If this happens at the start of a large group of
2713 : : * NULL values, then we shouldn't expect to be called again until after
2714 : : * the scan has already read indefinitely-many leaf pages full of tuples
2715 : : * with NULL suffix values. (_bt_first is expected to skip over the group
2716 : : * of NULLs by applying a similar "deduce NOT NULL" rule of its own, which
2717 : : * involves consing up an explicit SK_SEARCHNOTNULL key.)
2718 : : *
2719 : : * Apply a test against finaltup to detect and recover from the problem:
2720 : : * if even finaltup doesn't satisfy such an inequality, we just skip by
2721 : : * starting a new primitive index scan. When we skip, we know for sure
2722 : : * that all of the tuples on the current page following caller's tuple are
2723 : : * also before the _bt_first-wise start of tuples for our new qual. That
2724 : : * at least suggests many more skippable pages beyond the current page.
2725 : : * (when so->scanBehind and so->oppositeDirCheck are set, this'll happen
2726 : : * when we test the next page's finaltup/high key instead.)
2727 : : */
2728 [ + + + + ]: 80818 : else if (has_required_opposite_direction_only && pstate->finaltup &&
2729 [ + + ]: 2856 : unlikely(!_bt_oppodir_checkkeys(scan, dir, pstate->finaltup)))
2730 : 1 : goto new_prim_scan;
2731 : :
2732 : 80817 : continue_scan:
2733 : :
2734 : : /*
2735 : : * Stick with the ongoing primitive index scan for now.
2736 : : *
2737 : : * It's possible that later tuples will also turn out to have values that
2738 : : * are still < the now-current array keys (or > the current array keys).
2739 : : * Our caller will handle this by performing what amounts to a linear
2740 : : * search of the page, implemented by calling _bt_check_compare and then
2741 : : * _bt_tuple_before_array_skeys for each tuple.
2742 : : *
2743 : : * This approach has various advantages over a binary search of the page.
2744 : : * Repeated binary searches of the page (one binary search for every array
2745 : : * advancement) won't outperform a continuous linear search. While there
2746 : : * are workloads that a naive linear search won't handle well, our caller
2747 : : * has a "look ahead" fallback mechanism to deal with that problem.
2748 : : */
2749 : 83074 : pstate->continuescan = true; /* Override _bt_check_compare */
2750 : 83074 : so->needPrimScan = false; /* _bt_readpage has more tuples to check */
2751 : :
2752 [ + + ]: 83074 : if (so->scanBehind)
2753 : : {
2754 : : /*
2755 : : * Remember if recheck needs to call _bt_oppodir_checkkeys for next
2756 : : * page's finaltup (see above comments about "Handle inequalities
2757 : : * marked required in the opposite scan direction" for why).
2758 : : */
2759 : 2257 : so->oppositeDirCheck = has_required_opposite_direction_only;
2760 : :
2761 : : /*
2762 : : * skip by setting "look ahead" mechanism's offnum for forwards scans
2763 : : * (backwards scans check scanBehind flag directly instead)
2764 : : */
2765 [ + + ]: 2257 : if (ScanDirectionIsForward(dir))
2766 : 2245 : pstate->skip = pstate->maxoff + 1;
2767 : : }
2768 : :
2769 : : /* Caller's tuple doesn't match the new qual */
2770 : 83074 : return false;
2771 : :
2772 : 12098 : new_prim_scan:
2773 : :
2774 : : Assert(pstate->finaltup); /* not on rightmost/leftmost page */
2775 : :
2776 : : /*
2777 : : * Looks like another primitive index scan is required. But consider
2778 : : * continuing the current primscan based on scan-level heuristics.
2779 : : *
2780 : : * Continue the ongoing primitive scan (and schedule a recheck for when
2781 : : * the scan arrives on the next sibling leaf page) when it has already
2782 : : * read at least one leaf page before the one we're reading now. This
2783 : : * makes primscan scheduling more efficient when scanning subsets of an
2784 : : * index with many distinct attribute values matching many array elements.
2785 : : * It encourages fewer, larger primitive scans where that makes sense.
2786 : : * This will in turn encourage _bt_readpage to apply the pstate.startikey
2787 : : * optimization more often.
2788 : : *
2789 : : * Also continue the ongoing primitive index scan when it is still on the
2790 : : * first page if there have been more than NSKIPADVANCES_THRESHOLD calls
2791 : : * here that each advanced at least one of the scan's skip arrays
2792 : : * (deliberately ignore advancements that only affected SAOP arrays here).
2793 : : * A page that cycles through this many skip array elements is quite
2794 : : * likely to neighbor similar pages, that we'll also need to read.
2795 : : *
2796 : : * Note: These heuristics aren't as aggressive as you might think. We're
2797 : : * conservative about allowing a primitive scan to step from the first
2798 : : * leaf page it reads to the page's sibling page (we only allow it on
2799 : : * first pages whose finaltup strongly suggests that it'll work out, as
2800 : : * well as first pages that have a large number of skip array advances).
2801 : : * Clearing this first page finaltup hurdle is a strong signal in itself.
2802 : : *
2803 : : * Note: The NSKIPADVANCES_THRESHOLD heuristic exists only to avoid
2804 : : * pathological cases. Specifically, cases where a skip scan should just
2805 : : * behave like a traditional full index scan, but ends up "skipping" again
2806 : : * and again, descending to the prior leaf page's direct sibling leaf page
2807 : : * each time. This misbehavior would otherwise be possible during scans
2808 : : * that never quite manage to "clear the first page finaltup hurdle".
2809 : : */
2810 [ + + + + ]: 12098 : if (!pstate->firstpage || pstate->nskipadvances > NSKIPADVANCES_THRESHOLD)
2811 : : {
2812 : : /* Schedule a recheck once on the next (or previous) page */
2813 : 595 : so->scanBehind = true;
2814 : :
2815 : : /* Continue the current primitive scan after all */
2816 : 595 : goto continue_scan;
2817 : : }
2818 : :
2819 : : /*
2820 : : * End this primitive index scan, but schedule another.
2821 : : *
2822 : : * Note: We make a soft assumption that the current scan direction will
2823 : : * also be used within _bt_next, when it is asked to step off this page.
2824 : : * It is up to _bt_next to cancel this scheduled primitive index scan
2825 : : * whenever it steps to a page in the direction opposite currPos.dir.
2826 : : */
2827 : 11503 : pstate->continuescan = false; /* Tell _bt_readpage we're done... */
2828 : 11503 : so->needPrimScan = true; /* ...but call _bt_first again */
2829 : :
2830 [ + + ]: 11503 : if (scan->parallel_scan)
2831 : 24 : _bt_parallel_primscan_schedule(scan, so->currPos.currPage);
2832 : :
2833 : : /* Caller's tuple doesn't match the new qual */
2834 : 11503 : return false;
2835 : :
2836 : 12962 : end_toplevel_scan:
2837 : :
2838 : : /*
2839 : : * End the current primitive index scan, but don't schedule another.
2840 : : *
2841 : : * This ends the entire top-level scan in the current scan direction.
2842 : : *
2843 : : * Note: The scan's arrays (including any non-required arrays) are now in
2844 : : * their final positions for the current scan direction. If the scan
2845 : : * direction happens to change, then the arrays will already be in their
2846 : : * first positions for what will then be the current scan direction.
2847 : : */
2848 : 12962 : pstate->continuescan = false; /* Tell _bt_readpage we're done... */
2849 : 12962 : so->needPrimScan = false; /* ...and don't call _bt_first again */
2850 : :
2851 : : /* Caller's tuple doesn't match any qual */
2852 : 12962 : return false;
2853 : : }
2854 : :
2855 : : /*
2856 : : * _bt_advance_array_keys_increment() -- Advance to next set of array elements
2857 : : *
2858 : : * Advances the array keys by a single increment in the current scan
2859 : : * direction. When there are multiple array keys this can roll over from the
2860 : : * lowest order array to higher order arrays.
2861 : : *
2862 : : * Returns true if there is another set of values to consider, false if not.
2863 : : * On true result, the scankeys are initialized with the next set of values.
2864 : : * On false result, the scankeys stay the same, and the array keys are not
2865 : : * advanced (every array remains at its final element for scan direction).
2866 : : */
2867 : : static bool
2868 : 27529 : _bt_advance_array_keys_increment(IndexScanDesc scan, ScanDirection dir,
2869 : : bool *skip_array_set)
2870 : : {
2871 : 27529 : Relation rel = scan->indexRelation;
2872 : 27529 : BTScanOpaque so = (BTScanOpaque) scan->opaque;
2873 : :
2874 : : /*
2875 : : * We must advance the last array key most quickly, since it will
2876 : : * correspond to the lowest-order index column among the available
2877 : : * qualifications
2878 : : */
2879 [ + + ]: 41417 : for (int i = so->numArrayKeys - 1; i >= 0; i--)
2880 : : {
2881 : 28455 : BTArrayKeyInfo *array = &so->arrayKeys[i];
2882 : 28455 : ScanKey skey = &so->keyData[array->scan_key];
2883 : :
2884 [ + + ]: 28455 : if (array->num_elems == -1)
2885 : 15524 : *skip_array_set = true;
2886 : :
2887 [ + + ]: 28455 : if (ScanDirectionIsForward(dir))
2888 : : {
2889 [ + + ]: 27847 : if (_bt_array_increment(rel, skey, array))
2890 : 13983 : return true;
2891 : : }
2892 : : else
2893 : : {
2894 [ + + ]: 608 : if (_bt_array_decrement(rel, skey, array))
2895 : 584 : return true;
2896 : : }
2897 : :
2898 : : /*
2899 : : * Couldn't increment (or decrement) array. Handle array roll over.
2900 : : *
2901 : : * Start over at the array's lowest sorting value (or its highest
2902 : : * value, for backward scans)...
2903 : : */
2904 : 13888 : _bt_array_set_low_or_high(rel, skey, array,
2905 : : ScanDirectionIsForward(dir));
2906 : :
2907 : : /* ...then increment (or decrement) next most significant array */
2908 : : }
2909 : :
2910 : : /*
2911 : : * The array keys are now exhausted.
2912 : : *
2913 : : * Restore the array keys to the state they were in immediately before we
2914 : : * were called. This ensures that the arrays only ever ratchet in the
2915 : : * current scan direction.
2916 : : *
2917 : : * Without this, scans could overlook matching tuples when the scan
2918 : : * direction gets reversed just before btgettuple runs out of items to
2919 : : * return, but just after _bt_readpage prepares all the items from the
2920 : : * scan's final page in so->currPos. When we're on the final page it is
2921 : : * typical for so->currPos to get invalidated once btgettuple finally
2922 : : * returns false, which'll effectively invalidate the scan's array keys.
2923 : : * That hasn't happened yet, though -- and in general it may never happen.
2924 : : */
2925 : 12962 : _bt_start_array_keys(scan, -dir);
2926 : :
2927 : 12962 : return false;
2928 : : }
2929 : :
2930 : : /*
2931 : : * _bt_array_increment() -- increment array scan key's sk_argument
2932 : : *
2933 : : * Return value indicates whether caller's array was successfully incremented.
2934 : : * Cannot increment an array whose current element is already the final one.
2935 : : */
2936 : : static bool
2937 : 27847 : _bt_array_increment(Relation rel, ScanKey skey, BTArrayKeyInfo *array)
2938 : : {
2939 : 27847 : bool oflow = false;
2940 : : Datum inc_sk_argument;
2941 : :
2942 : : Assert(skey->sk_flags & SK_SEARCHARRAY);
2943 : : Assert(!(skey->sk_flags & (SK_BT_MINVAL | SK_BT_NEXT | SK_BT_PRIOR)));
2944 : :
2945 : : /* SAOP array? */
2946 [ + + ]: 27847 : if (array->num_elems != -1)
2947 : : {
2948 : : Assert(!(skey->sk_flags & (SK_BT_SKIP | SK_BT_MINVAL | SK_BT_MAXVAL)));
2949 [ + + ]: 12907 : if (array->cur_elem < array->num_elems - 1)
2950 : : {
2951 : : /*
2952 : : * Just increment current element, and assign its datum to skey
2953 : : * (only skip arrays need us to free existing sk_argument memory)
2954 : : */
2955 : 59 : array->cur_elem++;
2956 : 59 : skey->sk_argument = array->elem_values[array->cur_elem];
2957 : :
2958 : : /* Successfully incremented array */
2959 : 59 : return true;
2960 : : }
2961 : :
2962 : : /* Cannot increment past final array element */
2963 : 12848 : return false;
2964 : : }
2965 : :
2966 : : /* Nope, this is a skip array */
2967 : : Assert(skey->sk_flags & SK_BT_SKIP);
2968 : :
2969 : : /*
2970 : : * The sentinel value that represents the maximum value within the range
2971 : : * of a skip array (often just +inf) is never incrementable
2972 : : */
2973 [ + + ]: 14940 : if (skey->sk_flags & SK_BT_MAXVAL)
2974 : 429 : return false;
2975 : :
2976 : : /*
2977 : : * When the current array element is NULL, and the highest sorting value
2978 : : * in the index is also NULL, we cannot increment past the final element
2979 : : */
2980 [ + + + + ]: 14511 : if ((skey->sk_flags & SK_ISNULL) && !(skey->sk_flags & SK_BT_NULLS_FIRST))
2981 : 567 : return false;
2982 : :
2983 : : /*
2984 : : * Opclasses without skip support "increment" the scan key's current
2985 : : * element by setting the NEXT flag. The true next value is determined by
2986 : : * repositioning to the first index tuple > existing sk_argument/current
2987 : : * array element. Note that this works in the usual way when the scan key
2988 : : * is already marked ISNULL (i.e. when the current element is NULL).
2989 : : */
2990 [ + + ]: 13944 : if (!array->sksup)
2991 : : {
2992 : : /* Successfully "incremented" array */
2993 : 7990 : skey->sk_flags |= SK_BT_NEXT;
2994 : 7990 : return true;
2995 : : }
2996 : :
2997 : : /*
2998 : : * Opclasses with skip support directly increment sk_argument
2999 : : */
3000 [ + + ]: 5954 : if (skey->sk_flags & SK_ISNULL)
3001 : : {
3002 : : Assert(skey->sk_flags & SK_BT_NULLS_FIRST);
3003 : :
3004 : : /*
3005 : : * Existing sk_argument/array element is NULL (for an IS NULL qual).
3006 : : *
3007 : : * "Increment" from NULL to the low_elem value provided by opclass
3008 : : * skip support routine.
3009 : : */
3010 : 24 : skey->sk_flags &= ~(SK_SEARCHNULL | SK_ISNULL);
3011 : 48 : skey->sk_argument = datumCopy(array->sksup->low_elem,
3012 : 24 : array->attbyval, array->attlen);
3013 : 24 : return true;
3014 : : }
3015 : :
3016 : : /*
3017 : : * Ask opclass support routine to provide incremented copy of existing
3018 : : * non-NULL sk_argument
3019 : : */
3020 : 5930 : inc_sk_argument = array->sksup->increment(rel, skey->sk_argument, &oflow);
3021 [ + + ]: 5930 : if (unlikely(oflow))
3022 : : {
3023 : : /* inc_sk_argument has undefined value (so no pfree) */
3024 [ + - + + ]: 20 : if (array->null_elem && !(skey->sk_flags & SK_BT_NULLS_FIRST))
3025 : : {
3026 : 8 : _bt_skiparray_set_isnull(rel, skey, array);
3027 : :
3028 : : /* Successfully "incremented" array to NULL */
3029 : 8 : return true;
3030 : : }
3031 : :
3032 : : /* Cannot increment past final array element */
3033 : 12 : return false;
3034 : : }
3035 : :
3036 : : /*
3037 : : * Successfully incremented sk_argument to a non-NULL value. Make sure
3038 : : * that the incremented value is still within the range of the array.
3039 : : */
3040 [ + + ]: 5910 : if (array->high_compare &&
3041 [ + + ]: 28 : !DatumGetBool(FunctionCall2Coll(&array->high_compare->sk_func,
3042 : 28 : array->high_compare->sk_collation,
3043 : : inc_sk_argument,
3044 : 28 : array->high_compare->sk_argument)))
3045 : : {
3046 : : /* Keep existing sk_argument after all */
3047 [ - + ]: 8 : if (!array->attbyval)
3048 : 0 : pfree(DatumGetPointer(inc_sk_argument));
3049 : :
3050 : : /* Cannot increment past final array element */
3051 : 8 : return false;
3052 : : }
3053 : :
3054 : : /* Accept value returned by opclass increment callback */
3055 [ - + - - ]: 5902 : if (!array->attbyval && skey->sk_argument)
3056 : 0 : pfree(DatumGetPointer(skey->sk_argument));
3057 : 5902 : skey->sk_argument = inc_sk_argument;
3058 : :
3059 : : /* Successfully incremented array */
3060 : 5902 : return true;
3061 : : }
3062 : :
3063 : : /*
3064 : : * _bt_array_decrement() -- decrement array scan key's sk_argument
3065 : : *
3066 : : * Return value indicates whether caller's array was successfully decremented.
3067 : : * Cannot decrement an array whose current element is already the first one.
3068 : : */
3069 : : static bool
3070 : 608 : _bt_array_decrement(Relation rel, ScanKey skey, BTArrayKeyInfo *array)
3071 : : {
3072 : 608 : bool uflow = false;
3073 : : Datum dec_sk_argument;
3074 : :
3075 : : Assert(skey->sk_flags & SK_SEARCHARRAY);
3076 : : Assert(!(skey->sk_flags & (SK_BT_MAXVAL | SK_BT_NEXT | SK_BT_PRIOR)));
3077 : :
3078 : : /* SAOP array? */
3079 [ + + ]: 608 : if (array->num_elems != -1)
3080 : : {
3081 : : Assert(!(skey->sk_flags & (SK_BT_SKIP | SK_BT_MINVAL | SK_BT_MAXVAL)));
3082 [ + + ]: 24 : if (array->cur_elem > 0)
3083 : : {
3084 : : /*
3085 : : * Just decrement current element, and assign its datum to skey
3086 : : * (only skip arrays need us to free existing sk_argument memory)
3087 : : */
3088 : 4 : array->cur_elem--;
3089 : 4 : skey->sk_argument = array->elem_values[array->cur_elem];
3090 : :
3091 : : /* Successfully decremented array */
3092 : 4 : return true;
3093 : : }
3094 : :
3095 : : /* Cannot decrement to before first array element */
3096 : 20 : return false;
3097 : : }
3098 : :
3099 : : /* Nope, this is a skip array */
3100 : : Assert(skey->sk_flags & SK_BT_SKIP);
3101 : :
3102 : : /*
3103 : : * The sentinel value that represents the minimum value within the range
3104 : : * of a skip array (often just -inf) is never decrementable
3105 : : */
3106 [ - + ]: 584 : if (skey->sk_flags & SK_BT_MINVAL)
3107 : 0 : return false;
3108 : :
3109 : : /*
3110 : : * When the current array element is NULL, and the lowest sorting value in
3111 : : * the index is also NULL, we cannot decrement before first array element
3112 : : */
3113 [ + + - + ]: 584 : if ((skey->sk_flags & SK_ISNULL) && (skey->sk_flags & SK_BT_NULLS_FIRST))
3114 : 0 : return false;
3115 : :
3116 : : /*
3117 : : * Opclasses without skip support "decrement" the scan key's current
3118 : : * element by setting the PRIOR flag. The true prior value is determined
3119 : : * by repositioning to the last index tuple < existing sk_argument/current
3120 : : * array element. Note that this works in the usual way when the scan key
3121 : : * is already marked ISNULL (i.e. when the current element is NULL).
3122 : : */
3123 [ + + ]: 584 : if (!array->sksup)
3124 : : {
3125 : : /* Successfully "decremented" array */
3126 : 8 : skey->sk_flags |= SK_BT_PRIOR;
3127 : 8 : return true;
3128 : : }
3129 : :
3130 : : /*
3131 : : * Opclasses with skip support directly decrement sk_argument
3132 : : */
3133 [ + + ]: 576 : if (skey->sk_flags & SK_ISNULL)
3134 : : {
3135 : : Assert(!(skey->sk_flags & SK_BT_NULLS_FIRST));
3136 : :
3137 : : /*
3138 : : * Existing sk_argument/array element is NULL (for an IS NULL qual).
3139 : : *
3140 : : * "Decrement" from NULL to the high_elem value provided by opclass
3141 : : * skip support routine.
3142 : : */
3143 : 4 : skey->sk_flags &= ~(SK_SEARCHNULL | SK_ISNULL);
3144 : 8 : skey->sk_argument = datumCopy(array->sksup->high_elem,
3145 : 4 : array->attbyval, array->attlen);
3146 : 4 : return true;
3147 : : }
3148 : :
3149 : : /*
3150 : : * Ask opclass support routine to provide decremented copy of existing
3151 : : * non-NULL sk_argument
3152 : : */
3153 : 572 : dec_sk_argument = array->sksup->decrement(rel, skey->sk_argument, &uflow);
3154 [ - + ]: 572 : if (unlikely(uflow))
3155 : : {
3156 : : /* dec_sk_argument has undefined value (so no pfree) */
3157 [ # # # # ]: 0 : if (array->null_elem && (skey->sk_flags & SK_BT_NULLS_FIRST))
3158 : : {
3159 : 0 : _bt_skiparray_set_isnull(rel, skey, array);
3160 : :
3161 : : /* Successfully "decremented" array to NULL */
3162 : 0 : return true;
3163 : : }
3164 : :
3165 : : /* Cannot decrement to before first array element */
3166 : 0 : return false;
3167 : : }
3168 : :
3169 : : /*
3170 : : * Successfully decremented sk_argument to a non-NULL value. Make sure
3171 : : * that the decremented value is still within the range of the array.
3172 : : */
3173 [ + + ]: 572 : if (array->low_compare &&
3174 [ + + ]: 8 : !DatumGetBool(FunctionCall2Coll(&array->low_compare->sk_func,
3175 : 8 : array->low_compare->sk_collation,
3176 : : dec_sk_argument,
3177 : 8 : array->low_compare->sk_argument)))
3178 : : {
3179 : : /* Keep existing sk_argument after all */
3180 [ - + ]: 4 : if (!array->attbyval)
3181 : 0 : pfree(DatumGetPointer(dec_sk_argument));
3182 : :
3183 : : /* Cannot decrement to before first array element */
3184 : 4 : return false;
3185 : : }
3186 : :
3187 : : /* Accept value returned by opclass decrement callback */
3188 [ - + - - ]: 568 : if (!array->attbyval && skey->sk_argument)
3189 : 0 : pfree(DatumGetPointer(skey->sk_argument));
3190 : 568 : skey->sk_argument = dec_sk_argument;
3191 : :
3192 : : /* Successfully decremented array */
3193 : 568 : return true;
3194 : : }
3195 : :
3196 : : /*
3197 : : * _bt_array_set_low_or_high() -- Set array scan key to lowest/highest element
3198 : : *
3199 : : * Caller also passes associated scan key, which will have its argument set to
3200 : : * the lowest/highest array value in passing.
3201 : : */
3202 : : static void
3203 : 86908 : _bt_array_set_low_or_high(Relation rel, ScanKey skey, BTArrayKeyInfo *array,
3204 : : bool low_not_high)
3205 : : {
3206 : : Assert(skey->sk_flags & SK_SEARCHARRAY);
3207 : :
3208 [ + + ]: 86908 : if (array->num_elems != -1)
3209 : : {
3210 : : /* set low or high element for SAOP array */
3211 : 80549 : int set_elem = 0;
3212 : :
3213 : : Assert(!(skey->sk_flags & SK_BT_SKIP));
3214 : :
3215 [ + + ]: 80549 : if (!low_not_high)
3216 : 12866 : set_elem = array->num_elems - 1;
3217 : :
3218 : : /*
3219 : : * Just copy over array datum (only skip arrays require freeing and
3220 : : * allocating memory for sk_argument)
3221 : : */
3222 : 80549 : array->cur_elem = set_elem;
3223 : 80549 : skey->sk_argument = array->elem_values[set_elem];
3224 : :
3225 : 80549 : return;
3226 : : }
3227 : :
3228 : : /* set low or high element for skip array */
3229 : : Assert(skey->sk_flags & SK_BT_SKIP);
3230 : : Assert(array->num_elems == -1);
3231 : :
3232 : : /* Free memory previously allocated for sk_argument if needed */
3233 [ + + + + ]: 6359 : if (!array->attbyval && skey->sk_argument)
3234 : 1358 : pfree(DatumGetPointer(skey->sk_argument));
3235 : :
3236 : : /* Reset flags */
3237 : 6359 : skey->sk_argument = (Datum) 0;
3238 : 6359 : skey->sk_flags &= ~(SK_SEARCHNULL | SK_ISNULL |
3239 : : SK_BT_MINVAL | SK_BT_MAXVAL |
3240 : : SK_BT_NEXT | SK_BT_PRIOR);
3241 : :
3242 [ + + ]: 6359 : if (array->null_elem &&
3243 [ + + ]: 5161 : (low_not_high == ((skey->sk_flags & SK_BT_NULLS_FIRST) != 0)))
3244 : : {
3245 : : /* Requested element (either lowest or highest) has the value NULL */
3246 : 1194 : skey->sk_flags |= (SK_SEARCHNULL | SK_ISNULL);
3247 : : }
3248 [ + + ]: 5165 : else if (low_not_high)
3249 : : {
3250 : : /* Setting array to lowest element (according to low_compare) */
3251 : 4683 : skey->sk_flags |= SK_BT_MINVAL;
3252 : : }
3253 : : else
3254 : : {
3255 : : /* Setting array to highest element (according to high_compare) */
3256 : 482 : skey->sk_flags |= SK_BT_MAXVAL;
3257 : : }
3258 : : }
3259 : :
3260 : : /*
3261 : : * _bt_skiparray_set_element() -- Set skip array scan key's sk_argument
3262 : : *
3263 : : * Caller passes set_elem_result returned by _bt_binsrch_skiparray_skey for
3264 : : * caller's tupdatum/tupnull.
3265 : : *
3266 : : * We copy tupdatum/tupnull into skey's sk_argument iff set_elem_result == 0.
3267 : : * Otherwise, we set skey to either the lowest or highest value that's within
3268 : : * the range of caller's skip array (whichever is the best available match to
3269 : : * tupdatum/tupnull that is still within the range of the skip array according
3270 : : * to _bt_binsrch_skiparray_skey/set_elem_result).
3271 : : */
3272 : : static void
3273 : 95789 : _bt_skiparray_set_element(Relation rel, ScanKey skey, BTArrayKeyInfo *array,
3274 : : int32 set_elem_result, Datum tupdatum, bool tupnull)
3275 : : {
3276 : : Assert(skey->sk_flags & SK_BT_SKIP);
3277 : : Assert(skey->sk_flags & SK_SEARCHARRAY);
3278 : :
3279 [ + + ]: 95789 : if (set_elem_result)
3280 : : {
3281 : : /* tupdatum/tupnull is out of the range of the skip array */
3282 : : Assert(!array->null_elem);
3283 : :
3284 : 429 : _bt_array_set_low_or_high(rel, skey, array, set_elem_result < 0);
3285 : 429 : return;
3286 : : }
3287 : :
3288 : : /* Advance skip array to tupdatum (or tupnull) value */
3289 [ + + ]: 95360 : if (unlikely(tupnull))
3290 : : {
3291 : 24 : _bt_skiparray_set_isnull(rel, skey, array);
3292 : 24 : return;
3293 : : }
3294 : :
3295 : : /* Free memory previously allocated for sk_argument if needed */
3296 [ + + + + ]: 95336 : if (!array->attbyval && skey->sk_argument)
3297 : 39540 : pfree(DatumGetPointer(skey->sk_argument));
3298 : :
3299 : : /* tupdatum becomes new sk_argument/new current element */
3300 : 95336 : skey->sk_flags &= ~(SK_SEARCHNULL | SK_ISNULL |
3301 : : SK_BT_MINVAL | SK_BT_MAXVAL |
3302 : : SK_BT_NEXT | SK_BT_PRIOR);
3303 : 95336 : skey->sk_argument = datumCopy(tupdatum, array->attbyval, array->attlen);
3304 : : }
3305 : :
3306 : : /*
3307 : : * _bt_skiparray_set_isnull() -- set skip array scan key to NULL
3308 : : */
3309 : : static void
3310 : 32 : _bt_skiparray_set_isnull(Relation rel, ScanKey skey, BTArrayKeyInfo *array)
3311 : : {
3312 : : Assert(skey->sk_flags & SK_BT_SKIP);
3313 : : Assert(skey->sk_flags & SK_SEARCHARRAY);
3314 : : Assert(array->null_elem && !array->low_compare && !array->high_compare);
3315 : :
3316 : : /* Free memory previously allocated for sk_argument if needed */
3317 [ + + + - ]: 32 : if (!array->attbyval && skey->sk_argument)
3318 : 4 : pfree(DatumGetPointer(skey->sk_argument));
3319 : :
3320 : : /* NULL becomes new sk_argument/new current element */
3321 : 32 : skey->sk_argument = (Datum) 0;
3322 : 32 : skey->sk_flags &= ~(SK_BT_MINVAL | SK_BT_MAXVAL |
3323 : : SK_BT_NEXT | SK_BT_PRIOR);
3324 : 32 : skey->sk_flags |= (SK_SEARCHNULL | SK_ISNULL);
3325 : 32 : }
3326 : :
3327 : : /*
3328 : : * _bt_compare_array_skey() -- apply array comparison function
3329 : : *
3330 : : * Compares caller's tuple attribute value to a scan key/array element.
3331 : : * Helper function used during binary searches of SK_SEARCHARRAY arrays.
3332 : : *
3333 : : * This routine returns:
3334 : : * <0 if tupdatum < arrdatum;
3335 : : * 0 if tupdatum == arrdatum;
3336 : : * >0 if tupdatum > arrdatum.
3337 : : *
3338 : : * This is essentially the same interface as _bt_compare: both functions
3339 : : * compare the value that they're searching for to a binary search pivot.
3340 : : * However, unlike _bt_compare, this function's "tuple argument" comes first,
3341 : : * while its "array/scankey argument" comes second.
3342 : : */
3343 : : static inline int32
3344 : 1186266 : _bt_compare_array_skey(FmgrInfo *orderproc,
3345 : : Datum tupdatum, bool tupnull,
3346 : : Datum arrdatum, ScanKey cur)
3347 : : {
3348 : 1186266 : int32 result = 0;
3349 : :
3350 : : Assert(cur->sk_strategy == BTEqualStrategyNumber);
3351 : : Assert(!(cur->sk_flags & (SK_BT_MINVAL | SK_BT_MAXVAL)));
3352 : :
3353 [ + + ]: 1186266 : if (tupnull) /* NULL tupdatum */
3354 : : {
3355 [ + + ]: 158 : if (cur->sk_flags & SK_ISNULL)
3356 : 94 : result = 0; /* NULL "=" NULL */
3357 [ - + ]: 64 : else if (cur->sk_flags & SK_BT_NULLS_FIRST)
3358 : 0 : result = -1; /* NULL "<" NOT_NULL */
3359 : : else
3360 : 64 : result = 1; /* NULL ">" NOT_NULL */
3361 : : }
3362 [ + + ]: 1186108 : else if (cur->sk_flags & SK_ISNULL) /* NOT_NULL tupdatum, NULL arrdatum */
3363 : : {
3364 [ + + ]: 20360 : if (cur->sk_flags & SK_BT_NULLS_FIRST)
3365 : 36 : result = 1; /* NOT_NULL ">" NULL */
3366 : : else
3367 : 20324 : result = -1; /* NOT_NULL "<" NULL */
3368 : : }
3369 : : else
3370 : : {
3371 : : /*
3372 : : * Like _bt_compare, we need to be careful of cross-type comparisons,
3373 : : * so the left value has to be the value that came from an index tuple
3374 : : */
3375 : 1165748 : result = DatumGetInt32(FunctionCall2Coll(orderproc, cur->sk_collation,
3376 : : tupdatum, arrdatum));
3377 : :
3378 : : /*
3379 : : * We flip the sign by following the obvious rule: flip whenever the
3380 : : * column is a DESC column.
3381 : : *
3382 : : * _bt_compare does it the wrong way around (flip when *ASC*) in order
3383 : : * to compensate for passing its orderproc arguments backwards. We
3384 : : * don't need to play these games because we find it natural to pass
3385 : : * tupdatum as the left value (and arrdatum as the right value).
3386 : : */
3387 [ + + ]: 1165748 : if (cur->sk_flags & SK_BT_DESC)
3388 [ + + ]: 30332 : INVERT_COMPARE_RESULT(result);
3389 : : }
3390 : :
3391 : 1186266 : return result;
3392 : : }
3393 : :
3394 : : /*
3395 : : * _bt_binsrch_array_skey() -- Binary search for next matching array key
3396 : : *
3397 : : * Returns an index to the first array element >= caller's tupdatum argument.
3398 : : * This convention is more natural for forwards scan callers, but that can't
3399 : : * really matter to backwards scan callers. Both callers require handling for
3400 : : * the case where the match we return is < tupdatum, and symmetric handling
3401 : : * for the case where our best match is > tupdatum.
3402 : : *
3403 : : * Also sets *set_elem_result to the result _bt_compare_array_skey returned
3404 : : * when we used it to compare the matching array element to tupdatum/tupnull.
3405 : : *
3406 : : * cur_elem_trig indicates if array advancement was triggered by this array's
3407 : : * scan key, and that the array is for a required scan key. We can apply this
3408 : : * information to find the next matching array element in the current scan
3409 : : * direction using far fewer comparisons (fewer on average, compared to naive
3410 : : * binary search). This scheme takes advantage of an important property of
3411 : : * required arrays: required arrays always advance in lockstep with the index
3412 : : * scan's progress through the index's key space.
3413 : : */
3414 : : int
3415 : 428618 : _bt_binsrch_array_skey(FmgrInfo *orderproc,
3416 : : bool cur_elem_trig, ScanDirection dir,
3417 : : Datum tupdatum, bool tupnull,
3418 : : BTArrayKeyInfo *array, ScanKey cur,
3419 : : int32 *set_elem_result)
3420 : : {
3421 : 428618 : int low_elem = 0,
3422 : 428618 : mid_elem = -1,
3423 : 428618 : high_elem = array->num_elems - 1,
3424 : 428618 : result = 0;
3425 : : Datum arrdatum;
3426 : :
3427 : : Assert(cur->sk_flags & SK_SEARCHARRAY);
3428 : : Assert(!(cur->sk_flags & SK_BT_SKIP));
3429 : : Assert(!(cur->sk_flags & SK_ISNULL)); /* SAOP arrays never have NULLs */
3430 : : Assert(cur->sk_strategy == BTEqualStrategyNumber);
3431 : :
3432 [ + + ]: 428618 : if (cur_elem_trig)
3433 : : {
3434 : : Assert(!ScanDirectionIsNoMovement(dir));
3435 : : Assert(cur->sk_flags & SK_BT_REQFWD);
3436 : :
3437 : : /*
3438 : : * When the scan key that triggered array advancement is a required
3439 : : * array scan key, it is now certain that the current array element
3440 : : * (plus all prior elements relative to the current scan direction)
3441 : : * cannot possibly be at or ahead of the corresponding tuple value.
3442 : : * (_bt_checkkeys must have called _bt_tuple_before_array_skeys, which
3443 : : * makes sure this is true as a condition of advancing the arrays.)
3444 : : *
3445 : : * This makes it safe to exclude array elements up to and including
3446 : : * the former-current array element from our search.
3447 : : *
3448 : : * Separately, when array advancement was triggered by a required scan
3449 : : * key, the array element immediately after the former-current element
3450 : : * is often either an exact tupdatum match, or a "close by" near-match
3451 : : * (a near-match tupdatum is one whose key space falls _between_ the
3452 : : * former-current and new-current array elements). We'll detect both
3453 : : * cases via an optimistic comparison of the new search lower bound
3454 : : * (or new search upper bound in the case of backwards scans).
3455 : : */
3456 [ + + ]: 428405 : if (ScanDirectionIsForward(dir))
3457 : : {
3458 : 428365 : low_elem = array->cur_elem + 1; /* old cur_elem exhausted */
3459 : :
3460 : : /* Compare prospective new cur_elem (also the new lower bound) */
3461 [ + + ]: 428365 : if (high_elem >= low_elem)
3462 : : {
3463 : 415693 : arrdatum = array->elem_values[low_elem];
3464 : 415693 : result = _bt_compare_array_skey(orderproc, tupdatum, tupnull,
3465 : : arrdatum, cur);
3466 : :
3467 [ + + ]: 415693 : if (result <= 0)
3468 : : {
3469 : : /* Optimistic comparison optimization worked out */
3470 : 415636 : *set_elem_result = result;
3471 : 415636 : return low_elem;
3472 : : }
3473 : 57 : mid_elem = low_elem;
3474 : 57 : low_elem++; /* this cur_elem exhausted, too */
3475 : : }
3476 : :
3477 [ + + ]: 12729 : if (high_elem < low_elem)
3478 : : {
3479 : : /* Caller needs to perform "beyond end" array advancement */
3480 : 12676 : *set_elem_result = 1;
3481 : 12676 : return high_elem;
3482 : : }
3483 : : }
3484 : : else
3485 : : {
3486 : 40 : high_elem = array->cur_elem - 1; /* old cur_elem exhausted */
3487 : :
3488 : : /* Compare prospective new cur_elem (also the new upper bound) */
3489 [ + + ]: 40 : if (high_elem >= low_elem)
3490 : : {
3491 : 28 : arrdatum = array->elem_values[high_elem];
3492 : 28 : result = _bt_compare_array_skey(orderproc, tupdatum, tupnull,
3493 : : arrdatum, cur);
3494 : :
3495 [ + + ]: 28 : if (result >= 0)
3496 : : {
3497 : : /* Optimistic comparison optimization worked out */
3498 : 20 : *set_elem_result = result;
3499 : 20 : return high_elem;
3500 : : }
3501 : 8 : mid_elem = high_elem;
3502 : 8 : high_elem--; /* this cur_elem exhausted, too */
3503 : : }
3504 : :
3505 [ + - ]: 20 : if (high_elem < low_elem)
3506 : : {
3507 : : /* Caller needs to perform "beyond end" array advancement */
3508 : 20 : *set_elem_result = -1;
3509 : 20 : return low_elem;
3510 : : }
3511 : : }
3512 : : }
3513 : :
3514 [ + + ]: 467 : while (high_elem > low_elem)
3515 : : {
3516 : 293 : mid_elem = low_elem + ((high_elem - low_elem) / 2);
3517 : 293 : arrdatum = array->elem_values[mid_elem];
3518 : :
3519 : 293 : result = _bt_compare_array_skey(orderproc, tupdatum, tupnull,
3520 : : arrdatum, cur);
3521 : :
3522 [ + + ]: 293 : if (result == 0)
3523 : : {
3524 : : /*
3525 : : * It's safe to quit as soon as we see an equal array element.
3526 : : * This often saves an extra comparison or two...
3527 : : */
3528 : 92 : low_elem = mid_elem;
3529 : 92 : break;
3530 : : }
3531 : :
3532 [ + + ]: 201 : if (result > 0)
3533 : 180 : low_elem = mid_elem + 1;
3534 : : else
3535 : 21 : high_elem = mid_elem;
3536 : : }
3537 : :
3538 : : /*
3539 : : * ...but our caller also cares about how its searched-for tuple datum
3540 : : * compares to the low_elem datum. Must always set *set_elem_result with
3541 : : * the result of that comparison specifically.
3542 : : */
3543 [ + + ]: 266 : if (low_elem != mid_elem)
3544 : 161 : result = _bt_compare_array_skey(orderproc, tupdatum, tupnull,
3545 : 161 : array->elem_values[low_elem], cur);
3546 : :
3547 : 266 : *set_elem_result = result;
3548 : :
3549 : 266 : return low_elem;
3550 : : }
3551 : :
3552 : : /*
3553 : : * _bt_binsrch_skiparray_skey() -- "Binary search" within a skip array
3554 : : *
3555 : : * Does not return an index into the array, since skip arrays don't really
3556 : : * contain elements (they generate their array elements procedurally instead).
3557 : : * Our interface matches that of _bt_binsrch_array_skey in every other way.
3558 : : *
3559 : : * Sets *set_elem_result just like _bt_binsrch_array_skey would with a true
3560 : : * array. The value 0 indicates that tupdatum/tupnull is within the range of
3561 : : * the skip array. We return -1 when tupdatum/tupnull is lower that any value
3562 : : * within the range of the array, and 1 when it is higher than every value.
3563 : : * Caller should pass *set_elem_result to _bt_skiparray_set_element to advance
3564 : : * the array.
3565 : : *
3566 : : * cur_elem_trig indicates if array advancement was triggered by this array's
3567 : : * scan key. We use this to optimize-away comparisons that are known by our
3568 : : * caller to be unnecessary from context, just like _bt_binsrch_array_skey.
3569 : : */
3570 : : static void
3571 : 103265 : _bt_binsrch_skiparray_skey(bool cur_elem_trig, ScanDirection dir,
3572 : : Datum tupdatum, bool tupnull,
3573 : : BTArrayKeyInfo *array, ScanKey cur,
3574 : : int32 *set_elem_result)
3575 : : {
3576 : : Assert(cur->sk_flags & SK_BT_SKIP);
3577 : : Assert(cur->sk_flags & SK_SEARCHARRAY);
3578 : : Assert(cur->sk_flags & SK_BT_REQFWD);
3579 : : Assert(array->num_elems == -1);
3580 : : Assert(!ScanDirectionIsNoMovement(dir));
3581 : :
3582 [ + + ]: 103265 : if (array->null_elem)
3583 : : {
3584 : : Assert(!array->low_compare && !array->high_compare);
3585 : :
3586 : 86210 : *set_elem_result = 0;
3587 : 86210 : return;
3588 : : }
3589 : :
3590 [ + + ]: 17055 : if (tupnull) /* NULL tupdatum */
3591 : : {
3592 [ - + ]: 16 : if (cur->sk_flags & SK_BT_NULLS_FIRST)
3593 : 0 : *set_elem_result = -1; /* NULL "<" NOT_NULL */
3594 : : else
3595 : 16 : *set_elem_result = 1; /* NULL ">" NOT_NULL */
3596 : 16 : return;
3597 : : }
3598 : :
3599 : : /*
3600 : : * Array inequalities determine whether tupdatum is within the range of
3601 : : * caller's skip array
3602 : : */
3603 : 17039 : *set_elem_result = 0;
3604 [ + + ]: 17039 : if (ScanDirectionIsForward(dir))
3605 : : {
3606 : : /*
3607 : : * Evaluate low_compare first (unless cur_elem_trig tells us that it
3608 : : * cannot possibly fail to be satisfied), then evaluate high_compare
3609 : : */
3610 [ + + + + ]: 17007 : if (!cur_elem_trig && array->low_compare &&
3611 [ - + ]: 469 : !DatumGetBool(FunctionCall2Coll(&array->low_compare->sk_func,
3612 : 469 : array->low_compare->sk_collation,
3613 : : tupdatum,
3614 : 469 : array->low_compare->sk_argument)))
3615 : 0 : *set_elem_result = -1;
3616 [ + + ]: 17007 : else if (array->high_compare &&
3617 [ + + ]: 6279 : !DatumGetBool(FunctionCall2Coll(&array->high_compare->sk_func,
3618 : 6279 : array->high_compare->sk_collation,
3619 : : tupdatum,
3620 : 6279 : array->high_compare->sk_argument)))
3621 : 4275 : *set_elem_result = 1;
3622 : : }
3623 : : else
3624 : : {
3625 : : /*
3626 : : * Evaluate high_compare first (unless cur_elem_trig tells us that it
3627 : : * cannot possibly fail to be satisfied), then evaluate low_compare
3628 : : */
3629 [ + + + + ]: 32 : if (!cur_elem_trig && array->high_compare &&
3630 [ - + ]: 4 : !DatumGetBool(FunctionCall2Coll(&array->high_compare->sk_func,
3631 : 4 : array->high_compare->sk_collation,
3632 : : tupdatum,
3633 : 4 : array->high_compare->sk_argument)))
3634 : 0 : *set_elem_result = 1;
3635 [ + + ]: 32 : else if (array->low_compare &&
3636 [ - + ]: 16 : !DatumGetBool(FunctionCall2Coll(&array->low_compare->sk_func,
3637 : 16 : array->low_compare->sk_collation,
3638 : : tupdatum,
3639 : 16 : array->low_compare->sk_argument)))
3640 : 0 : *set_elem_result = -1;
3641 : : }
3642 : :
3643 : : /*
3644 : : * Assert that any keys that were assumed to be satisfied already (due to
3645 : : * caller passing cur_elem_trig=true) really are satisfied as expected
3646 : : */
3647 : : #ifdef USE_ASSERT_CHECKING
3648 : : if (cur_elem_trig)
3649 : : {
3650 : : if (ScanDirectionIsForward(dir) && array->low_compare)
3651 : : Assert(DatumGetBool(FunctionCall2Coll(&array->low_compare->sk_func,
3652 : : array->low_compare->sk_collation,
3653 : : tupdatum,
3654 : : array->low_compare->sk_argument)));
3655 : :
3656 : : if (ScanDirectionIsBackward(dir) && array->high_compare)
3657 : : Assert(DatumGetBool(FunctionCall2Coll(&array->high_compare->sk_func,
3658 : : array->high_compare->sk_collation,
3659 : : tupdatum,
3660 : : array->high_compare->sk_argument)));
3661 : : }
3662 : : #endif
3663 : : }
3664 : :
3665 : : #ifdef USE_ASSERT_CHECKING
3666 : : /*
3667 : : * Verify that the scan's "so->keyData[]" scan keys are in agreement with
3668 : : * its array key state
3669 : : */
3670 : : static bool
3671 : : _bt_verify_keys_with_arraykeys(IndexScanDesc scan)
3672 : : {
3673 : : BTScanOpaque so = (BTScanOpaque) scan->opaque;
3674 : : int last_sk_attno = InvalidAttrNumber,
3675 : : arrayidx = 0;
3676 : : bool nonrequiredseen = false;
3677 : :
3678 : : if (!so->qual_ok)
3679 : : return false;
3680 : :
3681 : : for (int ikey = 0; ikey < so->numberOfKeys; ikey++)
3682 : : {
3683 : : ScanKey cur = so->keyData + ikey;
3684 : : BTArrayKeyInfo *array;
3685 : :
3686 : : if (cur->sk_strategy != BTEqualStrategyNumber ||
3687 : : !(cur->sk_flags & SK_SEARCHARRAY))
3688 : : continue;
3689 : :
3690 : : array = &so->arrayKeys[arrayidx++];
3691 : : if (array->scan_key != ikey)
3692 : : return false;
3693 : :
3694 : : if (array->num_elems == 0 || array->num_elems < -1)
3695 : : return false;
3696 : :
3697 : : if (array->num_elems != -1 &&
3698 : : cur->sk_argument != array->elem_values[array->cur_elem])
3699 : : return false;
3700 : : if (cur->sk_flags & (SK_BT_REQFWD | SK_BT_REQBKWD))
3701 : : {
3702 : : if (last_sk_attno > cur->sk_attno)
3703 : : return false;
3704 : : if (nonrequiredseen)
3705 : : return false;
3706 : : }
3707 : : else
3708 : : nonrequiredseen = true;
3709 : :
3710 : : last_sk_attno = cur->sk_attno;
3711 : : }
3712 : :
3713 : : if (arrayidx != so->numArrayKeys)
3714 : : return false;
3715 : :
3716 : : return true;
3717 : : }
3718 : : #endif
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