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1 : : /*-------------------------------------------------------------------------
2 : : *
3 : : * tableam.h
4 : : * POSTGRES table access method definitions.
5 : : *
6 : : *
7 : : * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group
8 : : * Portions Copyright (c) 1994, Regents of the University of California
9 : : *
10 : : * src/include/access/tableam.h
11 : : *
12 : : * NOTES
13 : : * See tableam.sgml for higher level documentation.
14 : : *
15 : : *-------------------------------------------------------------------------
16 : : */
17 : : #ifndef TABLEAM_H
18 : : #define TABLEAM_H
19 : :
20 : : #include "access/relscan.h"
21 : : #include "access/sdir.h"
22 : : #include "access/xact.h"
23 : : #include "executor/tuptable.h"
24 : : #include "storage/read_stream.h"
25 : : #include "utils/rel.h"
26 : : #include "utils/snapshot.h"
27 : :
28 : :
29 : : #define DEFAULT_TABLE_ACCESS_METHOD "heap"
30 : :
31 : : /* GUCs */
32 : : extern PGDLLIMPORT char *default_table_access_method;
33 : : extern PGDLLIMPORT bool synchronize_seqscans;
34 : :
35 : :
36 : : /* forward references in this file */
37 : : typedef struct BulkInsertStateData BulkInsertStateData;
38 : : typedef struct IndexInfo IndexInfo;
39 : : typedef struct SampleScanState SampleScanState;
40 : : typedef struct ScanKeyData ScanKeyData;
41 : : typedef struct ValidateIndexState ValidateIndexState;
42 : : typedef struct VacuumParams VacuumParams;
43 : :
44 : : /*
45 : : * Bitmask values for the flags argument to the scan_begin callback.
46 : : */
47 : : typedef enum ScanOptions
48 : : {
49 : : SO_NONE = 0,
50 : :
51 : : /* one of SO_TYPE_* may be specified */
52 : : SO_TYPE_SEQSCAN = 1 << 0,
53 : : SO_TYPE_BITMAPSCAN = 1 << 1,
54 : : SO_TYPE_SAMPLESCAN = 1 << 2,
55 : : SO_TYPE_TIDSCAN = 1 << 3,
56 : : SO_TYPE_TIDRANGESCAN = 1 << 4,
57 : : SO_TYPE_ANALYZE = 1 << 5,
58 : :
59 : : /* several of SO_ALLOW_* may be specified */
60 : : /* allow or disallow use of access strategy */
61 : : SO_ALLOW_STRAT = 1 << 6,
62 : : /* report location to syncscan logic? */
63 : : SO_ALLOW_SYNC = 1 << 7,
64 : : /* verify visibility page-at-a-time? */
65 : : SO_ALLOW_PAGEMODE = 1 << 8,
66 : :
67 : : /* unregister snapshot at scan end? */
68 : : SO_TEMP_SNAPSHOT = 1 << 9,
69 : :
70 : : /* set if the query doesn't modify the relation */
71 : : SO_HINT_REL_READ_ONLY = 1 << 10,
72 : :
73 : : /* collect scan instrumentation */
74 : : SO_SCAN_INSTRUMENT = 1 << 11,
75 : : } ScanOptions;
76 : :
77 : : /*
78 : : * Mask of flags that are set internally by the table scan functions and
79 : : * shouldn't be passed by callers. Some of these are effectively set by callers
80 : : * through parameters to table scan functions (e.g. SO_ALLOW_STRAT/allow_strat),
81 : : * however, for now, retain tight control over them and don't allow users to
82 : : * pass these themselves to table scan functions.
83 : : */
84 : : #define SO_INTERNAL_FLAGS \
85 : : (SO_TYPE_SEQSCAN | SO_TYPE_BITMAPSCAN | SO_TYPE_SAMPLESCAN | \
86 : : SO_TYPE_TIDSCAN | SO_TYPE_TIDRANGESCAN | SO_TYPE_ANALYZE | \
87 : : SO_ALLOW_STRAT | SO_ALLOW_SYNC | SO_ALLOW_PAGEMODE | \
88 : : SO_TEMP_SNAPSHOT)
89 : :
90 : : /*
91 : : * Result codes for table_{update,delete,lock_tuple}, and for visibility
92 : : * routines inside table AMs.
93 : : */
94 : : typedef enum TM_Result
95 : : {
96 : : /*
97 : : * Signals that the action succeeded (i.e. update/delete performed, lock
98 : : * was acquired)
99 : : */
100 : : TM_Ok,
101 : :
102 : : /* The affected tuple wasn't visible to the relevant snapshot */
103 : : TM_Invisible,
104 : :
105 : : /* The affected tuple was already modified by the calling backend */
106 : : TM_SelfModified,
107 : :
108 : : /*
109 : : * The affected tuple was updated by another transaction. This includes
110 : : * the case where tuple was moved to another partition.
111 : : */
112 : : TM_Updated,
113 : :
114 : : /* The affected tuple was deleted by another transaction */
115 : : TM_Deleted,
116 : :
117 : : /*
118 : : * The affected tuple is currently being modified by another session. This
119 : : * will only be returned if table_(update/delete/lock_tuple) are
120 : : * instructed not to wait.
121 : : */
122 : : TM_BeingModified,
123 : :
124 : : /* lock couldn't be acquired, action skipped. Only used by lock_tuple */
125 : : TM_WouldBlock,
126 : : } TM_Result;
127 : :
128 : : /*
129 : : * Result codes for table_update(..., update_indexes*..).
130 : : * Used to determine which indexes to update.
131 : : */
132 : : typedef enum TU_UpdateIndexes
133 : : {
134 : : /* No indexed columns were updated (incl. TID addressing of tuple) */
135 : : TU_None,
136 : :
137 : : /* A non-summarizing indexed column was updated, or the TID has changed */
138 : : TU_All,
139 : :
140 : : /* Only summarized columns were updated, TID is unchanged */
141 : : TU_Summarizing,
142 : : } TU_UpdateIndexes;
143 : :
144 : : /*
145 : : * When table_tuple_update, table_tuple_delete, or table_tuple_lock fail
146 : : * because the target tuple is already outdated, they fill in this struct to
147 : : * provide information to the caller about what happened. When those functions
148 : : * succeed, the contents of this struct should not be relied upon, except for
149 : : * `traversed`, which may be set in both success and failure cases.
150 : : *
151 : : * ctid is the target's ctid link: it is the same as the target's TID if the
152 : : * target was deleted, or the location of the replacement tuple if the target
153 : : * was updated.
154 : : *
155 : : * xmax is the outdating transaction's XID. If the caller wants to visit the
156 : : * replacement tuple, it must check that this matches before believing the
157 : : * replacement is really a match. This is InvalidTransactionId if the target
158 : : * was !LP_NORMAL (expected only for a TID retrieved from syscache).
159 : : *
160 : : * cmax is the outdating command's CID, but only when the failure code is
161 : : * TM_SelfModified (i.e., something in the current transaction outdated the
162 : : * tuple); otherwise cmax is zero. (We make this restriction because
163 : : * HeapTupleHeaderGetCmax doesn't work for tuples outdated in other
164 : : * transactions.)
165 : : *
166 : : * traversed indicates if an update chain was followed in order to try to lock
167 : : * the target tuple. (This may be set in both success and failure cases.)
168 : : */
169 : : typedef struct TM_FailureData
170 : : {
171 : : ItemPointerData ctid;
172 : : TransactionId xmax;
173 : : CommandId cmax;
174 : : bool traversed;
175 : : } TM_FailureData;
176 : :
177 : : /*
178 : : * State used when calling table_index_delete_tuples().
179 : : *
180 : : * Represents the status of table tuples, referenced by table TID and taken by
181 : : * index AM from index tuples. State consists of high level parameters of the
182 : : * deletion operation, plus two mutable palloc()'d arrays for information
183 : : * about the status of individual table tuples. These are conceptually one
184 : : * single array. Using two arrays keeps the TM_IndexDelete struct small,
185 : : * which makes sorting the first array (the deltids array) fast.
186 : : *
187 : : * Some index AM callers perform simple index tuple deletion (by specifying
188 : : * bottomup = false), and include only known-dead deltids. These known-dead
189 : : * entries are all marked knowndeletable = true directly (typically these are
190 : : * TIDs from LP_DEAD-marked index tuples), but that isn't strictly required.
191 : : *
192 : : * Callers that specify bottomup = true are "bottom-up index deletion"
193 : : * callers. The considerations for the tableam are more subtle with these
194 : : * callers because they ask the tableam to perform highly speculative work,
195 : : * and might only expect the tableam to check a small fraction of all entries.
196 : : * Caller is not allowed to specify knowndeletable = true for any entry
197 : : * because everything is highly speculative. Bottom-up caller provides
198 : : * context and hints to tableam -- see comments below for details on how index
199 : : * AMs and tableams should coordinate during bottom-up index deletion.
200 : : *
201 : : * Simple index deletion callers may ask the tableam to perform speculative
202 : : * work, too. This is a little like bottom-up deletion, but not too much.
203 : : * The tableam will only perform speculative work when it's practically free
204 : : * to do so in passing for simple deletion caller (while always performing
205 : : * whatever work is needed to enable knowndeletable/LP_DEAD index tuples to
206 : : * be deleted within index AM). This is the real reason why it's possible for
207 : : * simple index deletion caller to specify knowndeletable = false up front
208 : : * (this means "check if it's possible for me to delete corresponding index
209 : : * tuple when it's cheap to do so in passing"). The index AM should only
210 : : * include "extra" entries for index tuples whose TIDs point to a table block
211 : : * that tableam is expected to have to visit anyway (in the event of a block
212 : : * orientated tableam). The tableam isn't strictly obligated to check these
213 : : * "extra" TIDs, but a block-based AM should always manage to do so in
214 : : * practice.
215 : : *
216 : : * The final contents of the deltids/status arrays are interesting to callers
217 : : * that ask tableam to perform speculative work (i.e. when _any_ items have
218 : : * knowndeletable set to false up front). These index AM callers will
219 : : * naturally need to consult final state to determine which index tuples are
220 : : * in fact deletable.
221 : : *
222 : : * The index AM can keep track of which index tuple relates to which deltid by
223 : : * setting idxoffnum (and/or relying on each entry being uniquely identifiable
224 : : * using tid), which is important when the final contents of the array will
225 : : * need to be interpreted -- the array can shrink from initial size after
226 : : * tableam processing and/or have entries in a new order (tableam may sort
227 : : * deltids array for its own reasons). Bottom-up callers may find that final
228 : : * ndeltids is 0 on return from call to tableam, in which case no index tuple
229 : : * deletions are possible. Simple deletion callers can rely on any entries
230 : : * they know to be deletable appearing in the final array as deletable.
231 : : */
232 : : typedef struct TM_IndexDelete
233 : : {
234 : : ItemPointerData tid; /* table TID from index tuple */
235 : : int16 id; /* Offset into TM_IndexStatus array */
236 : : } TM_IndexDelete;
237 : :
238 : : typedef struct TM_IndexStatus
239 : : {
240 : : OffsetNumber idxoffnum; /* Index am page offset number */
241 : : bool knowndeletable; /* Currently known to be deletable? */
242 : :
243 : : /* Bottom-up index deletion specific fields follow */
244 : : bool promising; /* Promising (duplicate) index tuple? */
245 : : int16 freespace; /* Space freed in index if deleted */
246 : : } TM_IndexStatus;
247 : :
248 : : /*
249 : : * Index AM/tableam coordination is central to the design of bottom-up index
250 : : * deletion. The index AM provides hints about where to look to the tableam
251 : : * by marking some entries as "promising". Index AM does this with duplicate
252 : : * index tuples that are strongly suspected to be old versions left behind by
253 : : * UPDATEs that did not logically modify indexed values. Index AM may find it
254 : : * helpful to only mark entries as promising when they're thought to have been
255 : : * affected by such an UPDATE in the recent past.
256 : : *
257 : : * Bottom-up index deletion casts a wide net at first, usually by including
258 : : * all TIDs on a target index page. It is up to the tableam to worry about
259 : : * the cost of checking transaction status information. The tableam is in
260 : : * control, but needs careful guidance from the index AM. Index AM requests
261 : : * that bottomupfreespace target be met, while tableam measures progress
262 : : * towards that goal by tallying the per-entry freespace value for known
263 : : * deletable entries. (All !bottomup callers can just set these space related
264 : : * fields to zero.)
265 : : */
266 : : typedef struct TM_IndexDeleteOp
267 : : {
268 : : Relation irel; /* Target index relation */
269 : : BlockNumber iblknum; /* Index block number (for error reports) */
270 : : bool bottomup; /* Bottom-up (not simple) deletion? */
271 : : int bottomupfreespace; /* Bottom-up space target */
272 : :
273 : : /* Mutable per-TID information follows (index AM initializes entries) */
274 : : int ndeltids; /* Current # of deltids/status elements */
275 : : TM_IndexDelete *deltids;
276 : : TM_IndexStatus *status;
277 : : } TM_IndexDeleteOp;
278 : :
279 : : /*
280 : : * "options" flag bits for table_tuple_insert. Access methods may define
281 : : * their own bits for internal use, as long as they don't collide with these.
282 : : */
283 : : /* TABLE_INSERT_SKIP_WAL was 0x0001; RelationNeedsWAL() now governs */
284 : : #define TABLE_INSERT_SKIP_FSM 0x0002
285 : : #define TABLE_INSERT_FROZEN 0x0004
286 : : #define TABLE_INSERT_NO_LOGICAL 0x0008
287 : :
288 : : /* "options" flag bits for table_tuple_delete */
289 : : #define TABLE_DELETE_CHANGING_PARTITION (1 << 0)
290 : : #define TABLE_DELETE_NO_LOGICAL (1 << 1)
291 : :
292 : : /* "options" flag bits for table_tuple_update */
293 : : #define TABLE_UPDATE_NO_LOGICAL (1 << 0)
294 : :
295 : : /* flag bits for table_tuple_lock */
296 : : /* Follow tuples whose update is in progress if lock modes don't conflict */
297 : : #define TUPLE_LOCK_FLAG_LOCK_UPDATE_IN_PROGRESS (1 << 0)
298 : : /* Follow update chain and lock latest version of tuple */
299 : : #define TUPLE_LOCK_FLAG_FIND_LAST_VERSION (1 << 1)
300 : :
301 : :
302 : : /* Typedef for callback function for table_index_build_scan */
303 : : typedef void (*IndexBuildCallback) (Relation index,
304 : : ItemPointer tid,
305 : : Datum *values,
306 : : bool *isnull,
307 : : bool tupleIsAlive,
308 : : void *state);
309 : :
310 : : /*
311 : : * API struct for a table AM. Note this must be allocated in a
312 : : * server-lifetime manner, typically as a static const struct, which then gets
313 : : * returned by FormData_pg_am.amhandler.
314 : : *
315 : : * In most cases it's not appropriate to call the callbacks directly, use the
316 : : * table_* wrapper functions instead.
317 : : *
318 : : * GetTableAmRoutine() asserts that required callbacks are filled in, remember
319 : : * to update when adding a callback.
320 : : */
321 : : typedef struct TableAmRoutine
322 : : {
323 : : /* this must be set to T_TableAmRoutine */
324 : : NodeTag type;
325 : :
326 : :
327 : : /* ------------------------------------------------------------------------
328 : : * Slot related callbacks.
329 : : * ------------------------------------------------------------------------
330 : : */
331 : :
332 : : /*
333 : : * Return slot implementation suitable for storing a tuple of this AM.
334 : : */
335 : : const TupleTableSlotOps *(*slot_callbacks) (Relation rel);
336 : :
337 : :
338 : : /* ------------------------------------------------------------------------
339 : : * Table scan callbacks.
340 : : * ------------------------------------------------------------------------
341 : : */
342 : :
343 : : /*
344 : : * Start a scan of `rel`. The callback has to return a TableScanDesc,
345 : : * which will typically be embedded in a larger, AM specific, struct.
346 : : *
347 : : * If nkeys != 0, the results need to be filtered by those scan keys.
348 : : *
349 : : * pscan, if not NULL, will have already been initialized with
350 : : * parallelscan_initialize(), and has to be for the same relation. Will
351 : : * only be set coming from table_beginscan_parallel().
352 : : *
353 : : * `flags` is a bitmask indicating the type of scan (ScanOptions's
354 : : * SO_TYPE_*, currently only one may be specified), options controlling
355 : : * the scan's behaviour (ScanOptions's SO_ALLOW_*, several may be
356 : : * specified, an AM may ignore unsupported ones), whether the snapshot
357 : : * needs to be deallocated at scan_end (ScanOptions's SO_TEMP_SNAPSHOT),
358 : : * and any number of the other ScanOptions values.
359 : : */
360 : : TableScanDesc (*scan_begin) (Relation rel,
361 : : Snapshot snapshot,
362 : : int nkeys, ScanKeyData *key,
363 : : ParallelTableScanDesc pscan,
364 : : uint32 flags);
365 : :
366 : : /*
367 : : * Release resources and deallocate scan. If TableScanDesc.temp_snap,
368 : : * TableScanDesc.rs_snapshot needs to be unregistered.
369 : : */
370 : : void (*scan_end) (TableScanDesc scan);
371 : :
372 : : /*
373 : : * Restart relation scan. If set_params is set to true, allow_{strat,
374 : : * sync, pagemode} (see scan_begin) changes should be taken into account.
375 : : */
376 : : void (*scan_rescan) (TableScanDesc scan, ScanKeyData *key,
377 : : bool set_params, bool allow_strat,
378 : : bool allow_sync, bool allow_pagemode);
379 : :
380 : : /*
381 : : * Return next tuple from `scan`, store in slot.
382 : : */
383 : : bool (*scan_getnextslot) (TableScanDesc scan,
384 : : ScanDirection direction,
385 : : TupleTableSlot *slot);
386 : :
387 : : /*-----------
388 : : * Optional functions to provide scanning for ranges of ItemPointers.
389 : : * Implementations must either provide both of these functions, or neither
390 : : * of them.
391 : : *
392 : : * Implementations of scan_set_tidrange must themselves handle
393 : : * ItemPointers of any value. i.e, they must handle each of the following:
394 : : *
395 : : * 1) mintid or maxtid is beyond the end of the table; and
396 : : * 2) mintid is above maxtid; and
397 : : * 3) item offset for mintid or maxtid is beyond the maximum offset
398 : : * allowed by the AM.
399 : : *
400 : : * Implementations can assume that scan_set_tidrange is always called
401 : : * before scan_getnextslot_tidrange or after scan_rescan and before any
402 : : * further calls to scan_getnextslot_tidrange.
403 : : */
404 : : void (*scan_set_tidrange) (TableScanDesc scan,
405 : : ItemPointer mintid,
406 : : ItemPointer maxtid);
407 : :
408 : : /*
409 : : * Return next tuple from `scan` that's in the range of TIDs defined by
410 : : * scan_set_tidrange.
411 : : */
412 : : bool (*scan_getnextslot_tidrange) (TableScanDesc scan,
413 : : ScanDirection direction,
414 : : TupleTableSlot *slot);
415 : :
416 : : /* ------------------------------------------------------------------------
417 : : * Parallel table scan related functions.
418 : : * ------------------------------------------------------------------------
419 : : */
420 : :
421 : : /*
422 : : * Estimate the size of shared memory needed for a parallel scan of this
423 : : * relation. The snapshot does not need to be accounted for.
424 : : */
425 : : Size (*parallelscan_estimate) (Relation rel);
426 : :
427 : : /*
428 : : * Initialize ParallelTableScanDesc for a parallel scan of this relation.
429 : : * `pscan` will be sized according to parallelscan_estimate() for the same
430 : : * relation.
431 : : */
432 : : Size (*parallelscan_initialize) (Relation rel,
433 : : ParallelTableScanDesc pscan);
434 : :
435 : : /*
436 : : * Reinitialize `pscan` for a new scan. `rel` will be the same relation as
437 : : * when `pscan` was initialized by parallelscan_initialize.
438 : : */
439 : : void (*parallelscan_reinitialize) (Relation rel,
440 : : ParallelTableScanDesc pscan);
441 : :
442 : :
443 : : /* ------------------------------------------------------------------------
444 : : * Index Scan Callbacks
445 : : * ------------------------------------------------------------------------
446 : : */
447 : :
448 : : /*
449 : : * Prepare to fetch tuples from the relation, as needed when fetching
450 : : * tuples for an index scan. The callback has to return an
451 : : * IndexFetchTableData, which the AM will typically embed in a larger
452 : : * structure with additional information.
453 : : *
454 : : * flags is a bitmask of ScanOptions affecting underlying table scan
455 : : * behavior. See scan_begin() for more information on passing these.
456 : : *
457 : : * Tuples for an index scan can then be fetched via index_fetch_tuple.
458 : : */
459 : : struct IndexFetchTableData *(*index_fetch_begin) (Relation rel, uint32 flags);
460 : :
461 : : /*
462 : : * Reset index fetch. Typically this will release cross index fetch
463 : : * resources held in IndexFetchTableData.
464 : : */
465 : : void (*index_fetch_reset) (struct IndexFetchTableData *data);
466 : :
467 : : /*
468 : : * Release resources and deallocate index fetch.
469 : : */
470 : : void (*index_fetch_end) (struct IndexFetchTableData *data);
471 : :
472 : : /*
473 : : * Fetch tuple at `tid` into `slot`, after doing a visibility test
474 : : * according to `snapshot`. If a tuple was found and passed the visibility
475 : : * test, return true, false otherwise.
476 : : *
477 : : * Note that AMs that do not necessarily update indexes when indexed
478 : : * columns do not change, need to return the current/correct version of
479 : : * the tuple that is visible to the snapshot, even if the tid points to an
480 : : * older version of the tuple.
481 : : *
482 : : * *call_again is false on the first call to index_fetch_tuple for a tid.
483 : : * If there potentially is another tuple matching the tid, *call_again
484 : : * needs to be set to true by index_fetch_tuple, signaling to the caller
485 : : * that index_fetch_tuple should be called again for the same tid.
486 : : *
487 : : * *all_dead, if all_dead is not NULL, should be set to true by
488 : : * index_fetch_tuple iff it is guaranteed that no backend needs to see
489 : : * that tuple. Index AMs can use that to avoid returning that tid in
490 : : * future searches.
491 : : */
492 : : bool (*index_fetch_tuple) (struct IndexFetchTableData *scan,
493 : : ItemPointer tid,
494 : : Snapshot snapshot,
495 : : TupleTableSlot *slot,
496 : : bool *call_again, bool *all_dead);
497 : :
498 : :
499 : : /* ------------------------------------------------------------------------
500 : : * Callbacks for non-modifying operations on individual tuples
501 : : * ------------------------------------------------------------------------
502 : : */
503 : :
504 : : /*
505 : : * Fetch tuple at `tid` into `slot`, after doing a visibility test
506 : : * according to `snapshot`. If a tuple was found and passed the visibility
507 : : * test, returns true, false otherwise.
508 : : */
509 : : bool (*tuple_fetch_row_version) (Relation rel,
510 : : ItemPointer tid,
511 : : Snapshot snapshot,
512 : : TupleTableSlot *slot);
513 : :
514 : : /*
515 : : * Is tid valid for a scan of this relation.
516 : : */
517 : : bool (*tuple_tid_valid) (TableScanDesc scan,
518 : : ItemPointer tid);
519 : :
520 : : /*
521 : : * Return the latest version of the tuple at `tid`, by updating `tid` to
522 : : * point at the newest version.
523 : : */
524 : : void (*tuple_get_latest_tid) (TableScanDesc scan,
525 : : ItemPointer tid);
526 : :
527 : : /*
528 : : * Does the tuple in `slot` satisfy `snapshot`? The slot needs to be of
529 : : * the appropriate type for the AM.
530 : : */
531 : : bool (*tuple_satisfies_snapshot) (Relation rel,
532 : : TupleTableSlot *slot,
533 : : Snapshot snapshot);
534 : :
535 : : /* see table_index_delete_tuples() */
536 : : TransactionId (*index_delete_tuples) (Relation rel,
537 : : TM_IndexDeleteOp *delstate);
538 : :
539 : :
540 : : /* ------------------------------------------------------------------------
541 : : * Manipulations of physical tuples.
542 : : * ------------------------------------------------------------------------
543 : : */
544 : :
545 : : /* see table_tuple_insert() for reference about parameters */
546 : : void (*tuple_insert) (Relation rel, TupleTableSlot *slot,
547 : : CommandId cid, uint32 options,
548 : : BulkInsertStateData *bistate);
549 : :
550 : : /* see table_tuple_insert_speculative() for reference about parameters */
551 : : void (*tuple_insert_speculative) (Relation rel,
552 : : TupleTableSlot *slot,
553 : : CommandId cid,
554 : : uint32 options,
555 : : BulkInsertStateData *bistate,
556 : : uint32 specToken);
557 : :
558 : : /* see table_tuple_complete_speculative() for reference about parameters */
559 : : void (*tuple_complete_speculative) (Relation rel,
560 : : TupleTableSlot *slot,
561 : : uint32 specToken,
562 : : bool succeeded);
563 : :
564 : : /* see table_multi_insert() for reference about parameters */
565 : : void (*multi_insert) (Relation rel, TupleTableSlot **slots, int nslots,
566 : : CommandId cid, uint32 options, BulkInsertStateData *bistate);
567 : :
568 : : /* see table_tuple_delete() for reference about parameters */
569 : : TM_Result (*tuple_delete) (Relation rel,
570 : : ItemPointer tid,
571 : : CommandId cid,
572 : : uint32 options,
573 : : Snapshot snapshot,
574 : : Snapshot crosscheck,
575 : : bool wait,
576 : : TM_FailureData *tmfd);
577 : :
578 : : /* see table_tuple_update() for reference about parameters */
579 : : TM_Result (*tuple_update) (Relation rel,
580 : : ItemPointer otid,
581 : : TupleTableSlot *slot,
582 : : CommandId cid,
583 : : uint32 options,
584 : : Snapshot snapshot,
585 : : Snapshot crosscheck,
586 : : bool wait,
587 : : TM_FailureData *tmfd,
588 : : LockTupleMode *lockmode,
589 : : TU_UpdateIndexes *update_indexes);
590 : :
591 : : /* see table_tuple_lock() for reference about parameters */
592 : : TM_Result (*tuple_lock) (Relation rel,
593 : : ItemPointer tid,
594 : : Snapshot snapshot,
595 : : TupleTableSlot *slot,
596 : : CommandId cid,
597 : : LockTupleMode mode,
598 : : LockWaitPolicy wait_policy,
599 : : uint8 flags,
600 : : TM_FailureData *tmfd);
601 : :
602 : : /*
603 : : * Perform operations necessary to complete insertions made via
604 : : * tuple_insert and multi_insert with a BulkInsertState specified. In-tree
605 : : * access methods ceased to use this.
606 : : *
607 : : * Typically callers of tuple_insert and multi_insert will just pass all
608 : : * the flags that apply to them, and each AM has to decide which of them
609 : : * make sense for it, and then only take actions in finish_bulk_insert for
610 : : * those flags, and ignore others.
611 : : *
612 : : * Optional callback.
613 : : */
614 : : void (*finish_bulk_insert) (Relation rel, uint32 options);
615 : :
616 : :
617 : : /* ------------------------------------------------------------------------
618 : : * DDL related functionality.
619 : : * ------------------------------------------------------------------------
620 : : */
621 : :
622 : : /*
623 : : * This callback needs to create new relation storage for `rel`, with
624 : : * appropriate durability behaviour for `persistence`.
625 : : *
626 : : * Note that only the subset of the relcache filled by
627 : : * RelationBuildLocalRelation() can be relied upon and that the relation's
628 : : * catalog entries will either not yet exist (new relation), or will still
629 : : * reference the old relfilelocator.
630 : : *
631 : : * As output *freezeXid, *minmulti must be set to the values appropriate
632 : : * for pg_class.{relfrozenxid, relminmxid}. For AMs that don't need those
633 : : * fields to be filled they can be set to InvalidTransactionId and
634 : : * InvalidMultiXactId, respectively.
635 : : *
636 : : * See also table_relation_set_new_filelocator().
637 : : */
638 : : void (*relation_set_new_filelocator) (Relation rel,
639 : : const RelFileLocator *newrlocator,
640 : : char persistence,
641 : : TransactionId *freezeXid,
642 : : MultiXactId *minmulti);
643 : :
644 : : /*
645 : : * This callback needs to remove all contents from `rel`'s current
646 : : * relfilelocator. No provisions for transactional behaviour need to be
647 : : * made. Often this can be implemented by truncating the underlying
648 : : * storage to its minimal size.
649 : : *
650 : : * See also table_relation_nontransactional_truncate().
651 : : */
652 : : void (*relation_nontransactional_truncate) (Relation rel);
653 : :
654 : : /*
655 : : * See table_relation_copy_data().
656 : : *
657 : : * This can typically be implemented by directly copying the underlying
658 : : * storage, unless it contains references to the tablespace internally.
659 : : */
660 : : void (*relation_copy_data) (Relation rel,
661 : : const RelFileLocator *newrlocator);
662 : :
663 : : /* See table_relation_copy_for_cluster() */
664 : : void (*relation_copy_for_cluster) (Relation OldTable,
665 : : Relation NewTable,
666 : : Relation OldIndex,
667 : : bool use_sort,
668 : : TransactionId OldestXmin,
669 : : Snapshot snapshot,
670 : : TransactionId *xid_cutoff,
671 : : MultiXactId *multi_cutoff,
672 : : double *num_tuples,
673 : : double *tups_vacuumed,
674 : : double *tups_recently_dead);
675 : :
676 : : /*
677 : : * React to VACUUM command on the relation. The VACUUM can be triggered by
678 : : * a user or by autovacuum. The specific actions performed by the AM will
679 : : * depend heavily on the individual AM.
680 : : *
681 : : * On entry a transaction is already established, and the relation is
682 : : * locked with a ShareUpdateExclusive lock.
683 : : *
684 : : * Note that neither VACUUM FULL (and CLUSTER), nor ANALYZE go through
685 : : * this routine, even if (for ANALYZE) it is part of the same VACUUM
686 : : * command.
687 : : *
688 : : * There probably, in the future, needs to be a separate callback to
689 : : * integrate with autovacuum's scheduling.
690 : : */
691 : : void (*relation_vacuum) (Relation rel,
692 : : const VacuumParams *params,
693 : : BufferAccessStrategy bstrategy);
694 : :
695 : : /*
696 : : * Prepare to analyze block `blockno` of `scan`. The scan has been started
697 : : * with table_beginscan_analyze(). See also
698 : : * table_scan_analyze_next_block().
699 : : *
700 : : * The callback may acquire resources like locks that are held until
701 : : * table_scan_analyze_next_tuple() returns false. It e.g. can make sense
702 : : * to hold a lock until all tuples on a block have been analyzed by
703 : : * scan_analyze_next_tuple.
704 : : *
705 : : * The callback can return false if the block is not suitable for
706 : : * sampling, e.g. because it's a metapage that could never contain tuples.
707 : : *
708 : : * XXX: This obviously is primarily suited for block-based AMs. It's not
709 : : * clear what a good interface for non block based AMs would be, so there
710 : : * isn't one yet.
711 : : */
712 : : bool (*scan_analyze_next_block) (TableScanDesc scan,
713 : : ReadStream *stream);
714 : :
715 : : /*
716 : : * See table_scan_analyze_next_tuple().
717 : : *
718 : : * Not every AM might have a meaningful concept of dead rows, in which
719 : : * case it's OK to not increment *deadrows - but note that that may
720 : : * influence autovacuum scheduling (see comment for relation_vacuum
721 : : * callback).
722 : : */
723 : : bool (*scan_analyze_next_tuple) (TableScanDesc scan,
724 : : double *liverows,
725 : : double *deadrows,
726 : : TupleTableSlot *slot);
727 : :
728 : : /* see table_index_build_range_scan for reference about parameters */
729 : : double (*index_build_range_scan) (Relation table_rel,
730 : : Relation index_rel,
731 : : IndexInfo *index_info,
732 : : bool allow_sync,
733 : : bool anyvisible,
734 : : bool progress,
735 : : BlockNumber start_blockno,
736 : : BlockNumber numblocks,
737 : : IndexBuildCallback callback,
738 : : void *callback_state,
739 : : TableScanDesc scan);
740 : :
741 : : /* see table_index_validate_scan for reference about parameters */
742 : : void (*index_validate_scan) (Relation table_rel,
743 : : Relation index_rel,
744 : : IndexInfo *index_info,
745 : : Snapshot snapshot,
746 : : ValidateIndexState *state);
747 : :
748 : :
749 : : /* ------------------------------------------------------------------------
750 : : * Miscellaneous functions.
751 : : * ------------------------------------------------------------------------
752 : : */
753 : :
754 : : /*
755 : : * See table_relation_size().
756 : : *
757 : : * Note that currently a few callers use the MAIN_FORKNUM size to figure
758 : : * out the range of potentially interesting blocks (brin, analyze). It's
759 : : * probable that we'll need to revise the interface for those at some
760 : : * point.
761 : : */
762 : : uint64 (*relation_size) (Relation rel, ForkNumber forkNumber);
763 : :
764 : :
765 : : /*
766 : : * This callback should return true if the relation requires a TOAST table
767 : : * and false if it does not. It may wish to examine the relation's tuple
768 : : * descriptor before making a decision, but if it uses some other method
769 : : * of storing large values (or if it does not support them) it can simply
770 : : * return false.
771 : : */
772 : : bool (*relation_needs_toast_table) (Relation rel);
773 : :
774 : : /*
775 : : * This callback should return the OID of the table AM that implements
776 : : * TOAST tables for this AM. If the relation_needs_toast_table callback
777 : : * always returns false, this callback is not required.
778 : : */
779 : : Oid (*relation_toast_am) (Relation rel);
780 : :
781 : : /*
782 : : * This callback is invoked when detoasting a value stored in a toast
783 : : * table implemented by this AM. See table_relation_fetch_toast_slice()
784 : : * for more details.
785 : : */
786 : : void (*relation_fetch_toast_slice) (Relation toastrel, Oid valueid,
787 : : int32 attrsize,
788 : : int32 sliceoffset,
789 : : int32 slicelength,
790 : : varlena *result);
791 : :
792 : :
793 : : /* ------------------------------------------------------------------------
794 : : * Planner related functions.
795 : : * ------------------------------------------------------------------------
796 : : */
797 : :
798 : : /*
799 : : * See table_relation_estimate_size().
800 : : *
801 : : * While block oriented, it shouldn't be too hard for an AM that doesn't
802 : : * internally use blocks to convert into a usable representation.
803 : : *
804 : : * This differs from the relation_size callback by returning size
805 : : * estimates (both relation size and tuple count) for planning purposes,
806 : : * rather than returning a currently correct estimate.
807 : : */
808 : : void (*relation_estimate_size) (Relation rel, int32 *attr_widths,
809 : : BlockNumber *pages, double *tuples,
810 : : double *allvisfrac);
811 : :
812 : :
813 : : /* ------------------------------------------------------------------------
814 : : * Executor related functions.
815 : : * ------------------------------------------------------------------------
816 : : */
817 : :
818 : : /*
819 : : * Fetch the next tuple of a bitmap table scan into `slot` and return true
820 : : * if a visible tuple was found, false otherwise.
821 : : *
822 : : * `lossy_pages` is incremented if the bitmap is lossy for the selected
823 : : * page; otherwise, `exact_pages` is incremented. These are tracked for
824 : : * display in EXPLAIN ANALYZE output.
825 : : *
826 : : * Prefetching additional data from the bitmap is left to the table AM.
827 : : *
828 : : * This is an optional callback.
829 : : */
830 : : bool (*scan_bitmap_next_tuple) (TableScanDesc scan,
831 : : TupleTableSlot *slot,
832 : : bool *recheck,
833 : : uint64 *lossy_pages,
834 : : uint64 *exact_pages);
835 : :
836 : : /*
837 : : * Prepare to fetch tuples from the next block in a sample scan. Return
838 : : * false if the sample scan is finished, true otherwise. `scan` was
839 : : * started via table_beginscan_sampling().
840 : : *
841 : : * Typically this will first determine the target block by calling the
842 : : * TsmRoutine's NextSampleBlock() callback if not NULL, or alternatively
843 : : * perform a sequential scan over all blocks. The determined block is
844 : : * then typically read and pinned.
845 : : *
846 : : * As the TsmRoutine interface is block based, a block needs to be passed
847 : : * to NextSampleBlock(). If that's not appropriate for an AM, it
848 : : * internally needs to perform mapping between the internal and a block
849 : : * based representation.
850 : : *
851 : : * Note that it's not acceptable to hold deadlock prone resources such as
852 : : * lwlocks until scan_sample_next_tuple() has exhausted the tuples on the
853 : : * block - the tuple is likely to be returned to an upper query node, and
854 : : * the next call could be off a long while. Holding buffer pins and such
855 : : * is obviously OK.
856 : : *
857 : : * Currently it is required to implement this interface, as there's no
858 : : * alternative way (contrary e.g. to bitmap scans) to implement sample
859 : : * scans. If infeasible to implement, the AM may raise an error.
860 : : */
861 : : bool (*scan_sample_next_block) (TableScanDesc scan,
862 : : SampleScanState *scanstate);
863 : :
864 : : /*
865 : : * This callback, only called after scan_sample_next_block has returned
866 : : * true, should determine the next tuple to be returned from the selected
867 : : * block using the TsmRoutine's NextSampleTuple() callback.
868 : : *
869 : : * The callback needs to perform visibility checks, and only return
870 : : * visible tuples. That obviously can mean calling NextSampleTuple()
871 : : * multiple times.
872 : : *
873 : : * The TsmRoutine interface assumes that there's a maximum offset on a
874 : : * given page, so if that doesn't apply to an AM, it needs to emulate that
875 : : * assumption somehow.
876 : : */
877 : : bool (*scan_sample_next_tuple) (TableScanDesc scan,
878 : : SampleScanState *scanstate,
879 : : TupleTableSlot *slot);
880 : :
881 : : } TableAmRoutine;
882 : :
883 : :
884 : : /* ----------------------------------------------------------------------------
885 : : * Slot functions.
886 : : * ----------------------------------------------------------------------------
887 : : */
888 : :
889 : : /*
890 : : * Returns slot callbacks suitable for holding tuples of the appropriate type
891 : : * for the relation. Works for tables, views, foreign tables and partitioned
892 : : * tables.
893 : : */
894 : : extern const TupleTableSlotOps *table_slot_callbacks(Relation relation);
895 : :
896 : : /*
897 : : * Returns slot using the callbacks returned by table_slot_callbacks(), and
898 : : * registers it on *reglist.
899 : : */
900 : : extern TupleTableSlot *table_slot_create(Relation relation, List **reglist);
901 : :
902 : :
903 : : /* ----------------------------------------------------------------------------
904 : : * Table scan functions.
905 : : * ----------------------------------------------------------------------------
906 : : */
907 : :
908 : : /*
909 : : * A wrapper around the Table Access Method scan_begin callback, to centralize
910 : : * error checking. All calls to ->scan_begin() should go through this
911 : : * function.
912 : : *
913 : : * The caller-provided user_flags are validated against SO_INTERNAL_FLAGS to
914 : : * catch callers that accidentally pass scan-type or other internal flags.
915 : : */
916 : : static TableScanDesc
917 : 485336 : table_beginscan_common(Relation rel, Snapshot snapshot, int nkeys,
918 : : ScanKeyData *key, ParallelTableScanDesc pscan,
919 : : uint32 flags, uint32 user_flags)
920 : : {
921 : : Assert((user_flags & SO_INTERNAL_FLAGS) == 0);
922 : : Assert((flags & ~SO_INTERNAL_FLAGS) == 0);
923 : 485336 : flags |= user_flags;
924 : :
925 : : /*
926 : : * We don't allow scans to be started while CheckXidAlive is set, except
927 : : * via systable_beginscan() et al. See detailed comments in xact.c where
928 : : * these variables are declared.
929 : : */
930 [ + + - + : 485336 : if (unlikely(TransactionIdIsValid(CheckXidAlive) && !bsysscan))
- + ]
931 [ # # ]: 0 : elog(ERROR, "scan started during logical decoding");
932 : :
933 : 485336 : return rel->rd_tableam->scan_begin(rel, snapshot, nkeys, key, pscan, flags);
934 : : }
935 : :
936 : : /*
937 : : * Start a scan of `rel`. Returned tuples pass a visibility test of
938 : : * `snapshot`, and if nkeys != 0, the results are filtered by those scan keys.
939 : : *
940 : : * flags is a bitmask of ScanOptions. No SO_INTERNAL_FLAGS are permitted.
941 : : */
942 : : static inline TableScanDesc
943 : 133189 : table_beginscan(Relation rel, Snapshot snapshot,
944 : : int nkeys, ScanKeyData *key, uint32 flags)
945 : : {
946 : 133189 : uint32 internal_flags = SO_TYPE_SEQSCAN |
947 : : SO_ALLOW_STRAT | SO_ALLOW_SYNC | SO_ALLOW_PAGEMODE;
948 : :
949 : 133189 : return table_beginscan_common(rel, snapshot, nkeys, key, NULL,
950 : : internal_flags, flags);
951 : : }
952 : :
953 : : /*
954 : : * Like table_beginscan(), but for scanning catalog. It'll automatically use a
955 : : * snapshot appropriate for scanning catalog relations.
956 : : */
957 : : extern TableScanDesc table_beginscan_catalog(Relation relation, int nkeys,
958 : : ScanKeyData *key);
959 : :
960 : : /*
961 : : * Like table_beginscan(), but table_beginscan_strat() offers an extended API
962 : : * that lets the caller control whether a nondefault buffer access strategy
963 : : * can be used, and whether syncscan can be chosen (possibly resulting in the
964 : : * scan not starting from block zero). Both of these default to true with
965 : : * plain table_beginscan.
966 : : */
967 : : static inline TableScanDesc
968 : 272711 : table_beginscan_strat(Relation rel, Snapshot snapshot,
969 : : int nkeys, ScanKeyData *key,
970 : : bool allow_strat, bool allow_sync)
971 : : {
972 : 272711 : uint32 flags = SO_TYPE_SEQSCAN | SO_ALLOW_PAGEMODE;
973 : :
974 [ + - ]: 272711 : if (allow_strat)
975 : 272711 : flags |= SO_ALLOW_STRAT;
976 [ + + ]: 272711 : if (allow_sync)
977 : 35027 : flags |= SO_ALLOW_SYNC;
978 : :
979 : 272711 : return table_beginscan_common(rel, snapshot, nkeys, key, NULL,
980 : : flags, SO_NONE);
981 : : }
982 : :
983 : : /*
984 : : * table_beginscan_bm is an alternative entry point for setting up a
985 : : * TableScanDesc for a bitmap heap scan. Although that scan technology is
986 : : * really quite unlike a standard seqscan, there is just enough commonality to
987 : : * make it worth using the same data structure.
988 : : *
989 : : * flags is a bitmask of ScanOptions. No SO_INTERNAL_FLAGS are permitted.
990 : : */
991 : : static inline TableScanDesc
992 : 13516 : table_beginscan_bm(Relation rel, Snapshot snapshot,
993 : : int nkeys, ScanKeyData *key, uint32 flags)
994 : : {
995 : 13516 : uint32 internal_flags = SO_TYPE_BITMAPSCAN | SO_ALLOW_PAGEMODE;
996 : :
997 : 13516 : return table_beginscan_common(rel, snapshot, nkeys, key, NULL,
998 : : internal_flags, flags);
999 : : }
1000 : :
1001 : : /*
1002 : : * table_beginscan_sampling is an alternative entry point for setting up a
1003 : : * TableScanDesc for a TABLESAMPLE scan. As with bitmap scans, it's worth
1004 : : * using the same data structure although the behavior is rather different.
1005 : : * In addition to the options offered by table_beginscan_strat, this call
1006 : : * also allows control of whether page-mode visibility checking is used.
1007 : : *
1008 : : * flags is a bitmask of ScanOptions. No SO_INTERNAL_FLAGS are permitted.
1009 : : */
1010 : : static inline TableScanDesc
1011 : 94 : table_beginscan_sampling(Relation rel, Snapshot snapshot,
1012 : : int nkeys, ScanKeyData *key,
1013 : : bool allow_strat, bool allow_sync,
1014 : : bool allow_pagemode, uint32 flags)
1015 : : {
1016 : 94 : uint32 internal_flags = SO_TYPE_SAMPLESCAN;
1017 : :
1018 [ + + ]: 94 : if (allow_strat)
1019 : 86 : internal_flags |= SO_ALLOW_STRAT;
1020 [ + + ]: 94 : if (allow_sync)
1021 : 44 : internal_flags |= SO_ALLOW_SYNC;
1022 [ + + ]: 94 : if (allow_pagemode)
1023 : 78 : internal_flags |= SO_ALLOW_PAGEMODE;
1024 : :
1025 : 94 : return table_beginscan_common(rel, snapshot, nkeys, key, NULL,
1026 : : internal_flags, flags);
1027 : : }
1028 : :
1029 : : /*
1030 : : * table_beginscan_tid is an alternative entry point for setting up a
1031 : : * TableScanDesc for a Tid scan. As with bitmap scans, it's worth using
1032 : : * the same data structure although the behavior is rather different.
1033 : : */
1034 : : static inline TableScanDesc
1035 : 483 : table_beginscan_tid(Relation rel, Snapshot snapshot)
1036 : : {
1037 : 483 : uint32 flags = SO_TYPE_TIDSCAN;
1038 : :
1039 : 483 : return table_beginscan_common(rel, snapshot, 0, NULL, NULL,
1040 : : flags, SO_NONE);
1041 : : }
1042 : :
1043 : : /*
1044 : : * table_beginscan_analyze is an alternative entry point for setting up a
1045 : : * TableScanDesc for an ANALYZE scan. As with bitmap scans, it's worth using
1046 : : * the same data structure although the behavior is rather different.
1047 : : */
1048 : : static inline TableScanDesc
1049 : 11192 : table_beginscan_analyze(Relation rel)
1050 : : {
1051 : 11192 : uint32 flags = SO_TYPE_ANALYZE;
1052 : :
1053 : 11192 : return table_beginscan_common(rel, NULL, 0, NULL, NULL,
1054 : : flags, SO_NONE);
1055 : : }
1056 : :
1057 : : /*
1058 : : * End relation scan.
1059 : : */
1060 : : static inline void
1061 : 482032 : table_endscan(TableScanDesc scan)
1062 : : {
1063 : 482032 : scan->rs_rd->rd_tableam->scan_end(scan);
1064 : 482032 : }
1065 : :
1066 : : /*
1067 : : * Restart a relation scan.
1068 : : */
1069 : : static inline void
1070 : 641855 : table_rescan(TableScanDesc scan, ScanKeyData *key)
1071 : : {
1072 : 641855 : scan->rs_rd->rd_tableam->scan_rescan(scan, key, false, false, false, false);
1073 : 641855 : }
1074 : :
1075 : : /*
1076 : : * Restart a relation scan after changing params.
1077 : : *
1078 : : * This call allows changing the buffer strategy, syncscan, and pagemode
1079 : : * options before starting a fresh scan. Note that although the actual use of
1080 : : * syncscan might change (effectively, enabling or disabling reporting), the
1081 : : * previously selected startblock will be kept.
1082 : : */
1083 : : static inline void
1084 : 19 : table_rescan_set_params(TableScanDesc scan, ScanKeyData *key,
1085 : : bool allow_strat, bool allow_sync, bool allow_pagemode)
1086 : : {
1087 : 19 : scan->rs_rd->rd_tableam->scan_rescan(scan, key, true,
1088 : : allow_strat, allow_sync,
1089 : : allow_pagemode);
1090 : 19 : }
1091 : :
1092 : : /*
1093 : : * Return next tuple from `scan`, store in slot.
1094 : : */
1095 : : static inline bool
1096 : 61698993 : table_scan_getnextslot(TableScanDesc sscan, ScanDirection direction, TupleTableSlot *slot)
1097 : : {
1098 : 61698993 : slot->tts_tableOid = RelationGetRelid(sscan->rs_rd);
1099 : :
1100 : : /* We don't expect actual scans using NoMovementScanDirection */
1101 : : Assert(direction == ForwardScanDirection ||
1102 : : direction == BackwardScanDirection);
1103 : :
1104 : 61698993 : return sscan->rs_rd->rd_tableam->scan_getnextslot(sscan, direction, slot);
1105 : : }
1106 : :
1107 : : /* ----------------------------------------------------------------------------
1108 : : * TID Range scanning related functions.
1109 : : * ----------------------------------------------------------------------------
1110 : : */
1111 : :
1112 : : /*
1113 : : * table_beginscan_tidrange is the entry point for setting up a TableScanDesc
1114 : : * for a TID range scan.
1115 : : *
1116 : : * flags is a bitmask of ScanOptions. No SO_INTERNAL_FLAGS are permitted.
1117 : : */
1118 : : static inline TableScanDesc
1119 : 1234 : table_beginscan_tidrange(Relation rel, Snapshot snapshot,
1120 : : ItemPointer mintid,
1121 : : ItemPointer maxtid, uint32 flags)
1122 : : {
1123 : : TableScanDesc sscan;
1124 : 1234 : uint32 internal_flags = SO_TYPE_TIDRANGESCAN | SO_ALLOW_PAGEMODE;
1125 : :
1126 : 1234 : sscan = table_beginscan_common(rel, snapshot, 0, NULL, NULL,
1127 : : internal_flags, flags);
1128 : :
1129 : : /* Set the range of TIDs to scan */
1130 : 1234 : sscan->rs_rd->rd_tableam->scan_set_tidrange(sscan, mintid, maxtid);
1131 : :
1132 : 1234 : return sscan;
1133 : : }
1134 : :
1135 : : /*
1136 : : * table_rescan_tidrange resets the scan position and sets the minimum and
1137 : : * maximum TID range to scan for a TableScanDesc created by
1138 : : * table_beginscan_tidrange.
1139 : : */
1140 : : static inline void
1141 : 140 : table_rescan_tidrange(TableScanDesc sscan, ItemPointer mintid,
1142 : : ItemPointer maxtid)
1143 : : {
1144 : : /* Ensure table_beginscan_tidrange() was used. */
1145 : : Assert((sscan->rs_flags & SO_TYPE_TIDRANGESCAN) != 0);
1146 : :
1147 : 140 : sscan->rs_rd->rd_tableam->scan_rescan(sscan, NULL, false, false, false, false);
1148 : 140 : sscan->rs_rd->rd_tableam->scan_set_tidrange(sscan, mintid, maxtid);
1149 : 140 : }
1150 : :
1151 : : /*
1152 : : * Fetch the next tuple from `sscan` for a TID range scan created by
1153 : : * table_beginscan_tidrange(). Stores the tuple in `slot` and returns true,
1154 : : * or returns false if no more tuples exist in the range.
1155 : : */
1156 : : static inline bool
1157 : 6512 : table_scan_getnextslot_tidrange(TableScanDesc sscan, ScanDirection direction,
1158 : : TupleTableSlot *slot)
1159 : : {
1160 : : /* Ensure table_beginscan_tidrange() was used. */
1161 : : Assert((sscan->rs_flags & SO_TYPE_TIDRANGESCAN) != 0);
1162 : :
1163 : : /* We don't expect actual scans using NoMovementScanDirection */
1164 : : Assert(direction == ForwardScanDirection ||
1165 : : direction == BackwardScanDirection);
1166 : :
1167 : 6512 : return sscan->rs_rd->rd_tableam->scan_getnextslot_tidrange(sscan,
1168 : : direction,
1169 : : slot);
1170 : : }
1171 : :
1172 : :
1173 : : /* ----------------------------------------------------------------------------
1174 : : * Parallel table scan related functions.
1175 : : * ----------------------------------------------------------------------------
1176 : : */
1177 : :
1178 : : /*
1179 : : * Estimate the size of shared memory needed for a parallel scan of this
1180 : : * relation.
1181 : : */
1182 : : extern Size table_parallelscan_estimate(Relation rel, Snapshot snapshot);
1183 : :
1184 : : /*
1185 : : * Initialize ParallelTableScanDesc for a parallel scan of this
1186 : : * relation. `pscan` needs to be sized according to parallelscan_estimate()
1187 : : * for the same relation. Call this just once in the leader process; then,
1188 : : * individual workers attach via table_beginscan_parallel.
1189 : : */
1190 : : extern void table_parallelscan_initialize(Relation rel,
1191 : : ParallelTableScanDesc pscan,
1192 : : Snapshot snapshot);
1193 : :
1194 : : /*
1195 : : * Begin a parallel scan. `pscan` needs to have been initialized with
1196 : : * table_parallelscan_initialize(), for the same relation. The initialization
1197 : : * does not need to have happened in this backend.
1198 : : *
1199 : : * flags is a bitmask of ScanOptions. No SO_INTERNAL_FLAGS are permitted.
1200 : : *
1201 : : * Caller must hold a suitable lock on the relation.
1202 : : */
1203 : : extern TableScanDesc table_beginscan_parallel(Relation relation,
1204 : : ParallelTableScanDesc pscan,
1205 : : uint32 flags);
1206 : :
1207 : : /*
1208 : : * Begin a parallel tid range scan. `pscan` needs to have been initialized
1209 : : * with table_parallelscan_initialize(), for the same relation. The
1210 : : * initialization does not need to have happened in this backend.
1211 : : *
1212 : : * flags is a bitmask of ScanOptions. No SO_INTERNAL_FLAGS are permitted.
1213 : : *
1214 : : * Caller must hold a suitable lock on the relation.
1215 : : */
1216 : : extern TableScanDesc table_beginscan_parallel_tidrange(Relation relation,
1217 : : ParallelTableScanDesc pscan,
1218 : : uint32 flags);
1219 : :
1220 : : /*
1221 : : * Restart a parallel scan. Call this in the leader process. Caller is
1222 : : * responsible for making sure that all workers have finished the scan
1223 : : * beforehand.
1224 : : */
1225 : : static inline void
1226 : 152 : table_parallelscan_reinitialize(Relation rel, ParallelTableScanDesc pscan)
1227 : : {
1228 : 152 : rel->rd_tableam->parallelscan_reinitialize(rel, pscan);
1229 : 152 : }
1230 : :
1231 : :
1232 : : /* ----------------------------------------------------------------------------
1233 : : * Index scan related functions.
1234 : : * ----------------------------------------------------------------------------
1235 : : */
1236 : :
1237 : : /*
1238 : : * Prepare to fetch tuples from the relation, as needed when fetching tuples
1239 : : * for an index scan.
1240 : : *
1241 : : * flags is a bitmask of ScanOptions. No SO_INTERNAL_FLAGS are permitted.
1242 : : *
1243 : : * Tuples for an index scan can then be fetched via table_index_fetch_tuple().
1244 : : */
1245 : : static inline IndexFetchTableData *
1246 : 17679517 : table_index_fetch_begin(Relation rel, uint32 flags)
1247 : : {
1248 : : Assert((flags & SO_INTERNAL_FLAGS) == 0);
1249 : :
1250 : : /*
1251 : : * We don't allow scans to be started while CheckXidAlive is set, except
1252 : : * via systable_beginscan() et al. See detailed comments in xact.c where
1253 : : * these variables are declared.
1254 : : */
1255 [ + + - + : 17679517 : if (unlikely(TransactionIdIsValid(CheckXidAlive) && !bsysscan))
- + ]
1256 [ # # ]: 0 : elog(ERROR, "scan started during logical decoding");
1257 : :
1258 : 17679517 : return rel->rd_tableam->index_fetch_begin(rel, flags);
1259 : : }
1260 : :
1261 : : /*
1262 : : * Reset index fetch. Typically this will release cross index fetch resources
1263 : : * held in IndexFetchTableData.
1264 : : */
1265 : : static inline void
1266 : 15100614 : table_index_fetch_reset(struct IndexFetchTableData *scan)
1267 : : {
1268 : 15100614 : scan->rel->rd_tableam->index_fetch_reset(scan);
1269 : 15100614 : }
1270 : :
1271 : : /*
1272 : : * Release resources and deallocate index fetch.
1273 : : */
1274 : : static inline void
1275 : 17678231 : table_index_fetch_end(struct IndexFetchTableData *scan)
1276 : : {
1277 : 17678231 : scan->rel->rd_tableam->index_fetch_end(scan);
1278 : 17678231 : }
1279 : :
1280 : : /*
1281 : : * Fetches, as part of an index scan, tuple at `tid` into `slot`, after doing
1282 : : * a visibility test according to `snapshot`. If a tuple was found and passed
1283 : : * the visibility test, returns true, false otherwise. Note that *tid may be
1284 : : * modified when we return true (see later remarks on multiple row versions
1285 : : * reachable via a single index entry).
1286 : : *
1287 : : * *call_again needs to be false on the first call to table_index_fetch_tuple() for
1288 : : * a tid. If there potentially is another tuple matching the tid, *call_again
1289 : : * will be set to true, signaling that table_index_fetch_tuple() should be called
1290 : : * again for the same tid.
1291 : : *
1292 : : * *all_dead, if all_dead is not NULL, will be set to true by
1293 : : * table_index_fetch_tuple() iff it is guaranteed that no backend needs to see
1294 : : * that tuple. Index AMs can use that to avoid returning that tid in future
1295 : : * searches.
1296 : : *
1297 : : * The difference between this function and table_tuple_fetch_row_version()
1298 : : * is that this function returns the currently visible version of a row if
1299 : : * the AM supports storing multiple row versions reachable via a single index
1300 : : * entry (like heap's HOT). Whereas table_tuple_fetch_row_version() only
1301 : : * evaluates the tuple exactly at `tid`. Outside of index entry ->table tuple
1302 : : * lookups, table_tuple_fetch_row_version() is what's usually needed.
1303 : : */
1304 : : static inline bool
1305 : 24734746 : table_index_fetch_tuple(struct IndexFetchTableData *scan,
1306 : : ItemPointer tid,
1307 : : Snapshot snapshot,
1308 : : TupleTableSlot *slot,
1309 : : bool *call_again, bool *all_dead)
1310 : : {
1311 : 24734746 : return scan->rel->rd_tableam->index_fetch_tuple(scan, tid, snapshot,
1312 : : slot, call_again,
1313 : : all_dead);
1314 : : }
1315 : :
1316 : : /*
1317 : : * This is a convenience wrapper around table_index_fetch_tuple() which
1318 : : * returns whether there are table tuple items corresponding to an index
1319 : : * entry. This likely is only useful to verify if there's a conflict in a
1320 : : * unique index.
1321 : : */
1322 : : extern bool table_index_fetch_tuple_check(Relation rel,
1323 : : ItemPointer tid,
1324 : : Snapshot snapshot,
1325 : : bool *all_dead);
1326 : :
1327 : :
1328 : : /* ------------------------------------------------------------------------
1329 : : * Functions for non-modifying operations on individual tuples
1330 : : * ------------------------------------------------------------------------
1331 : : */
1332 : :
1333 : :
1334 : : /*
1335 : : * Fetch tuple at `tid` into `slot`, after doing a visibility test according to
1336 : : * `snapshot`. If a tuple was found and passed the visibility test, returns
1337 : : * true, false otherwise.
1338 : : *
1339 : : * See table_index_fetch_tuple's comment about what the difference between
1340 : : * these functions is. It is correct to use this function outside of index
1341 : : * entry->table tuple lookups.
1342 : : */
1343 : : static inline bool
1344 : 2841394 : table_tuple_fetch_row_version(Relation rel,
1345 : : ItemPointer tid,
1346 : : Snapshot snapshot,
1347 : : TupleTableSlot *slot)
1348 : : {
1349 : : /*
1350 : : * We don't expect direct calls to table_tuple_fetch_row_version with
1351 : : * valid CheckXidAlive for catalog or regular tables. See detailed
1352 : : * comments in xact.c where these variables are declared.
1353 : : */
1354 [ - + - - : 2841394 : if (unlikely(TransactionIdIsValid(CheckXidAlive) && !bsysscan))
- + ]
1355 [ # # ]: 0 : elog(ERROR, "unexpected table_tuple_fetch_row_version call during logical decoding");
1356 : :
1357 : 2841394 : return rel->rd_tableam->tuple_fetch_row_version(rel, tid, snapshot, slot);
1358 : : }
1359 : :
1360 : : /*
1361 : : * Verify that `tid` is a potentially valid tuple identifier. That doesn't
1362 : : * mean that the pointed to row needs to exist or be visible, but that
1363 : : * attempting to fetch the row (e.g. with table_tuple_get_latest_tid() or
1364 : : * table_tuple_fetch_row_version()) should not error out if called with that
1365 : : * tid.
1366 : : *
1367 : : * `scan` needs to have been started via table_beginscan().
1368 : : */
1369 : : static inline bool
1370 : 253 : table_tuple_tid_valid(TableScanDesc scan, ItemPointer tid)
1371 : : {
1372 : 253 : return scan->rs_rd->rd_tableam->tuple_tid_valid(scan, tid);
1373 : : }
1374 : :
1375 : : /*
1376 : : * Return the latest version of the tuple at `tid`, by updating `tid` to
1377 : : * point at the newest version.
1378 : : */
1379 : : extern void table_tuple_get_latest_tid(TableScanDesc scan, ItemPointer tid);
1380 : :
1381 : : /*
1382 : : * Return true iff tuple in slot satisfies the snapshot.
1383 : : *
1384 : : * This assumes the slot's tuple is valid, and of the appropriate type for the
1385 : : * AM.
1386 : : *
1387 : : * Some AMs might modify the data underlying the tuple as a side-effect. If so
1388 : : * they ought to mark the relevant buffer dirty.
1389 : : */
1390 : : static inline bool
1391 : 772969 : table_tuple_satisfies_snapshot(Relation rel, TupleTableSlot *slot,
1392 : : Snapshot snapshot)
1393 : : {
1394 : 772969 : return rel->rd_tableam->tuple_satisfies_snapshot(rel, slot, snapshot);
1395 : : }
1396 : :
1397 : : /*
1398 : : * Determine which index tuples are safe to delete based on their table TID.
1399 : : *
1400 : : * Determines which entries from index AM caller's TM_IndexDeleteOp state
1401 : : * point to vacuumable table tuples. Entries that are found by tableam to be
1402 : : * vacuumable are naturally safe for index AM to delete, and so get directly
1403 : : * marked as deletable. See comments above TM_IndexDelete and comments above
1404 : : * TM_IndexDeleteOp for full details.
1405 : : *
1406 : : * Returns a snapshotConflictHorizon transaction ID that caller places in
1407 : : * its index deletion WAL record. This might be used during subsequent REDO
1408 : : * of the WAL record when in Hot Standby mode -- a recovery conflict for the
1409 : : * index deletion operation might be required on the standby.
1410 : : */
1411 : : static inline TransactionId
1412 : 8402 : table_index_delete_tuples(Relation rel, TM_IndexDeleteOp *delstate)
1413 : : {
1414 : 8402 : return rel->rd_tableam->index_delete_tuples(rel, delstate);
1415 : : }
1416 : :
1417 : :
1418 : : /* ----------------------------------------------------------------------------
1419 : : * Functions for manipulations of physical tuples.
1420 : : * ----------------------------------------------------------------------------
1421 : : */
1422 : :
1423 : : /*
1424 : : * Insert a tuple from a slot into table AM routine.
1425 : : *
1426 : : * The options bitmask allows the caller to specify options that may change the
1427 : : * behaviour of the AM. The AM will ignore options that it does not support.
1428 : : *
1429 : : * If the TABLE_INSERT_SKIP_FSM option is specified, AMs are free to not reuse
1430 : : * free space in the relation. This can save some cycles when we know the
1431 : : * relation is new and doesn't contain useful amounts of free space.
1432 : : * TABLE_INSERT_SKIP_FSM is commonly passed directly to
1433 : : * RelationGetBufferForTuple. See that method for more information.
1434 : : *
1435 : : * TABLE_INSERT_FROZEN should only be specified for inserts into
1436 : : * relation storage created during the current subtransaction and when
1437 : : * there are no prior snapshots or pre-existing portals open.
1438 : : * This causes rows to be frozen, which is an MVCC violation and
1439 : : * requires explicit options chosen by user.
1440 : : *
1441 : : * TABLE_INSERT_NO_LOGICAL force-disables the emitting of logical decoding
1442 : : * information for the tuple. This should solely be used during table rewrites
1443 : : * where RelationIsLogicallyLogged(relation) is not yet accurate for the new
1444 : : * relation.
1445 : : *
1446 : : * Note that most of these options will be applied when inserting into the
1447 : : * heap's TOAST table, too, if the tuple requires any out-of-line data.
1448 : : *
1449 : : * The BulkInsertState object (if any; bistate can be NULL for default
1450 : : * behavior) is also just passed through to RelationGetBufferForTuple. If
1451 : : * `bistate` is provided, table_finish_bulk_insert() needs to be called.
1452 : : *
1453 : : * On return the slot's tts_tid and tts_tableOid are updated to reflect the
1454 : : * insertion. But note that any toasting of fields within the slot is NOT
1455 : : * reflected in the slots contents.
1456 : : */
1457 : : static inline void
1458 : 10415486 : table_tuple_insert(Relation rel, TupleTableSlot *slot, CommandId cid,
1459 : : uint32 options, BulkInsertStateData *bistate)
1460 : : {
1461 : 10415486 : rel->rd_tableam->tuple_insert(rel, slot, cid, options,
1462 : : bistate);
1463 : 10415466 : }
1464 : :
1465 : : /*
1466 : : * Perform a "speculative insertion". These can be backed out afterwards
1467 : : * without aborting the whole transaction. Other sessions can wait for the
1468 : : * speculative insertion to be confirmed, turning it into a regular tuple, or
1469 : : * aborted, as if it never existed. Speculatively inserted tuples behave as
1470 : : * "value locks" of short duration, used to implement INSERT .. ON CONFLICT.
1471 : : *
1472 : : * A transaction having performed a speculative insertion has to either abort,
1473 : : * or finish the speculative insertion with
1474 : : * table_tuple_complete_speculative(succeeded = ...).
1475 : : */
1476 : : static inline void
1477 : 2230 : table_tuple_insert_speculative(Relation rel, TupleTableSlot *slot,
1478 : : CommandId cid, uint32 options,
1479 : : BulkInsertStateData *bistate,
1480 : : uint32 specToken)
1481 : : {
1482 : 2230 : rel->rd_tableam->tuple_insert_speculative(rel, slot, cid, options,
1483 : : bistate, specToken);
1484 : 2230 : }
1485 : :
1486 : : /*
1487 : : * Complete "speculative insertion" started in the same transaction. If
1488 : : * succeeded is true, the tuple is fully inserted, if false, it's removed.
1489 : : */
1490 : : static inline void
1491 : 2226 : table_tuple_complete_speculative(Relation rel, TupleTableSlot *slot,
1492 : : uint32 specToken, bool succeeded)
1493 : : {
1494 : 2226 : rel->rd_tableam->tuple_complete_speculative(rel, slot, specToken,
1495 : : succeeded);
1496 : 2226 : }
1497 : :
1498 : : /*
1499 : : * Insert multiple tuples into a table.
1500 : : *
1501 : : * This is like table_tuple_insert(), but inserts multiple tuples in one
1502 : : * operation. That's often faster than calling table_tuple_insert() in a loop,
1503 : : * because e.g. the AM can reduce WAL logging and page locking overhead.
1504 : : *
1505 : : * Except for taking `nslots` tuples as input, and an array of TupleTableSlots
1506 : : * in `slots`, the parameters for table_multi_insert() are the same as for
1507 : : * table_tuple_insert().
1508 : : *
1509 : : * Note: this leaks memory into the current memory context. You can create a
1510 : : * temporary context before calling this, if that's a problem.
1511 : : */
1512 : : static inline void
1513 : 1472 : table_multi_insert(Relation rel, TupleTableSlot **slots, int nslots,
1514 : : CommandId cid, uint32 options, BulkInsertStateData *bistate)
1515 : : {
1516 : 1472 : rel->rd_tableam->multi_insert(rel, slots, nslots,
1517 : : cid, options, bistate);
1518 : 1472 : }
1519 : :
1520 : : /*
1521 : : * Delete a tuple.
1522 : : *
1523 : : * NB: do not call this directly unless prepared to deal with
1524 : : * concurrent-update conditions. Use simple_table_tuple_delete instead.
1525 : : *
1526 : : * Input parameters:
1527 : : * rel - table to be modified (caller must hold suitable lock)
1528 : : * tid - TID of tuple to be deleted
1529 : : * cid - delete command ID (used for visibility test, and stored into
1530 : : * cmax if successful)
1531 : : * options - bitmask of options. Supported values:
1532 : : * TABLE_DELETE_CHANGING_PARTITION: the tuple is being moved to another
1533 : : * partition table due to an update of the partition key.
1534 : : * crosscheck - if not InvalidSnapshot, also check tuple against this
1535 : : * wait - true if should wait for any conflicting update to commit/abort
1536 : : *
1537 : : * Output parameters:
1538 : : * tmfd - filled in failure cases (see below)
1539 : : *
1540 : : * Normal, successful return value is TM_Ok, which means we did actually
1541 : : * delete it. Failure return codes are TM_SelfModified, TM_Updated, and
1542 : : * TM_BeingModified (the last only possible if wait == false).
1543 : : *
1544 : : * In the failure cases, the routine fills *tmfd with the tuple's t_ctid,
1545 : : * t_xmax, and, if possible, t_cmax. See comments for struct
1546 : : * TM_FailureData for additional info.
1547 : : */
1548 : : static inline TM_Result
1549 : 1061889 : table_tuple_delete(Relation rel, ItemPointer tid, CommandId cid,
1550 : : uint32 options, Snapshot snapshot, Snapshot crosscheck,
1551 : : bool wait, TM_FailureData *tmfd)
1552 : : {
1553 : 1061889 : return rel->rd_tableam->tuple_delete(rel, tid, cid, options,
1554 : : snapshot, crosscheck,
1555 : : wait, tmfd);
1556 : : }
1557 : :
1558 : : /*
1559 : : * Update a tuple.
1560 : : *
1561 : : * NB: do not call this directly unless you are prepared to deal with
1562 : : * concurrent-update conditions. Use simple_table_tuple_update instead.
1563 : : *
1564 : : * Input parameters:
1565 : : * rel - table to be modified (caller must hold suitable lock)
1566 : : * otid - TID of old tuple to be replaced
1567 : : * cid - update command ID (used for visibility test, and stored into
1568 : : * cmax/cmin if successful)
1569 : : * options - bitmask of options. No values are currently recognized.
1570 : : * crosscheck - if not InvalidSnapshot, also check old tuple against this
1571 : : * options - These allow the caller to specify options that may change the
1572 : : * behavior of the AM. The AM will ignore options that it does not support.
1573 : : * TABLE_UPDATE_NO_LOGICAL -- force-disables the emitting of logical
1574 : : * decoding information for the tuple.
1575 : : *
1576 : : * Output parameters:
1577 : : * slot - newly constructed tuple data to store
1578 : : * tmfd - filled in failure cases (see below)
1579 : : * lockmode - filled with lock mode acquired on tuple
1580 : : * update_indexes - in success cases this is set if new index entries
1581 : : * are required for this tuple; see TU_UpdateIndexes
1582 : : *
1583 : : * Normal, successful return value is TM_Ok, which means we did actually
1584 : : * update it. Failure return codes are TM_SelfModified, TM_Updated, and
1585 : : * TM_BeingModified (the last only possible if wait == false).
1586 : : *
1587 : : * On success, the slot's tts_tid and tts_tableOid are updated to match the new
1588 : : * stored tuple; in particular, slot->tts_tid is set to the TID where the
1589 : : * new tuple was inserted, and its HEAP_ONLY_TUPLE flag is set iff a HOT
1590 : : * update was done. However, any TOAST changes in the new tuple's
1591 : : * data are not reflected into *newtup.
1592 : : *
1593 : : * In the failure cases, the routine fills *tmfd with the tuple's t_ctid,
1594 : : * t_xmax, and, if possible, t_cmax. See comments for struct TM_FailureData
1595 : : * for additional info.
1596 : : */
1597 : : static inline TM_Result
1598 : 2246493 : table_tuple_update(Relation rel, ItemPointer otid, TupleTableSlot *slot,
1599 : : CommandId cid, uint32 options,
1600 : : Snapshot snapshot, Snapshot crosscheck,
1601 : : bool wait, TM_FailureData *tmfd, LockTupleMode *lockmode,
1602 : : TU_UpdateIndexes *update_indexes)
1603 : : {
1604 : 2246493 : return rel->rd_tableam->tuple_update(rel, otid, slot,
1605 : : cid, options, snapshot, crosscheck,
1606 : : wait, tmfd,
1607 : : lockmode, update_indexes);
1608 : : }
1609 : :
1610 : : /*
1611 : : * Lock a tuple in the specified mode.
1612 : : *
1613 : : * Input parameters:
1614 : : * rel: relation containing tuple (caller must hold suitable lock)
1615 : : * tid: TID of tuple to lock (updated if an update chain was followed)
1616 : : * snapshot: snapshot to use for visibility determinations
1617 : : * cid: current command ID (used for visibility test, and stored into
1618 : : * tuple's cmax if lock is successful)
1619 : : * mode: lock mode desired
1620 : : * wait_policy: what to do if tuple lock is not available
1621 : : * flags:
1622 : : * If TUPLE_LOCK_FLAG_LOCK_UPDATE_IN_PROGRESS, follow the update chain to
1623 : : * also lock descendant tuples if lock modes don't conflict.
1624 : : * If TUPLE_LOCK_FLAG_FIND_LAST_VERSION, follow the update chain and lock
1625 : : * latest version.
1626 : : *
1627 : : * Output parameters:
1628 : : * *slot: contains the target tuple
1629 : : * *tmfd: filled in failure cases (see below)
1630 : : *
1631 : : * Function result may be:
1632 : : * TM_Ok: lock was successfully acquired
1633 : : * TM_Invisible: lock failed because tuple was never visible to us
1634 : : * TM_SelfModified: lock failed because tuple updated by self
1635 : : * TM_Updated: lock failed because tuple updated by other xact
1636 : : * TM_Deleted: lock failed because tuple deleted by other xact
1637 : : * TM_WouldBlock: lock couldn't be acquired and wait_policy is skip
1638 : : *
1639 : : * In the failure cases other than TM_Invisible and TM_Deleted, the routine
1640 : : * fills *tmfd with the tuple's t_ctid, t_xmax, and, if possible, t_cmax.
1641 : : * Additionally, in both success and failure cases, tmfd->traversed is set if
1642 : : * an update chain was followed. See comments for struct TM_FailureData for
1643 : : * additional info.
1644 : : */
1645 : : static inline TM_Result
1646 : 571528 : table_tuple_lock(Relation rel, ItemPointer tid, Snapshot snapshot,
1647 : : TupleTableSlot *slot, CommandId cid, LockTupleMode mode,
1648 : : LockWaitPolicy wait_policy, uint8 flags,
1649 : : TM_FailureData *tmfd)
1650 : : {
1651 : 571528 : return rel->rd_tableam->tuple_lock(rel, tid, snapshot, slot,
1652 : : cid, mode, wait_policy,
1653 : : flags, tmfd);
1654 : : }
1655 : :
1656 : : /*
1657 : : * Perform operations necessary to complete insertions made via
1658 : : * tuple_insert and multi_insert with a BulkInsertState specified.
1659 : : */
1660 : : static inline void
1661 : 3241 : table_finish_bulk_insert(Relation rel, uint32 options)
1662 : : {
1663 : : /* optional callback */
1664 [ + - - + ]: 3241 : if (rel->rd_tableam && rel->rd_tableam->finish_bulk_insert)
1665 : 0 : rel->rd_tableam->finish_bulk_insert(rel, options);
1666 : 3241 : }
1667 : :
1668 : :
1669 : : /* ------------------------------------------------------------------------
1670 : : * DDL related functionality.
1671 : : * ------------------------------------------------------------------------
1672 : : */
1673 : :
1674 : : /*
1675 : : * Create storage for `rel` in `newrlocator`, with persistence set to
1676 : : * `persistence`.
1677 : : *
1678 : : * This is used both during relation creation and various DDL operations to
1679 : : * create new rel storage that can be filled from scratch. When creating
1680 : : * new storage for an existing relfilelocator, this should be called before the
1681 : : * relcache entry has been updated.
1682 : : *
1683 : : * *freezeXid, *minmulti are set to the xid / multixact horizon for the table
1684 : : * that pg_class.{relfrozenxid, relminmxid} have to be set to.
1685 : : */
1686 : : static inline void
1687 : 44211 : table_relation_set_new_filelocator(Relation rel,
1688 : : const RelFileLocator *newrlocator,
1689 : : char persistence,
1690 : : TransactionId *freezeXid,
1691 : : MultiXactId *minmulti)
1692 : : {
1693 : 44211 : rel->rd_tableam->relation_set_new_filelocator(rel, newrlocator,
1694 : : persistence, freezeXid,
1695 : : minmulti);
1696 : 44211 : }
1697 : :
1698 : : /*
1699 : : * Remove all table contents from `rel`, in a non-transactional manner.
1700 : : * Non-transactional meaning that there's no need to support rollbacks. This
1701 : : * commonly only is used to perform truncations for relation storage created in
1702 : : * the current transaction.
1703 : : */
1704 : : static inline void
1705 : 401 : table_relation_nontransactional_truncate(Relation rel)
1706 : : {
1707 : 401 : rel->rd_tableam->relation_nontransactional_truncate(rel);
1708 : 401 : }
1709 : :
1710 : : /*
1711 : : * Copy data from `rel` into the new relfilelocator `newrlocator`. The new
1712 : : * relfilelocator may not have storage associated before this function is
1713 : : * called. This is only supposed to be used for low level operations like
1714 : : * changing a relation's tablespace.
1715 : : */
1716 : : static inline void
1717 : 68 : table_relation_copy_data(Relation rel, const RelFileLocator *newrlocator)
1718 : : {
1719 : 68 : rel->rd_tableam->relation_copy_data(rel, newrlocator);
1720 : 68 : }
1721 : :
1722 : : /*
1723 : : * Copy data from `OldTable` into `NewTable`, as part of a CLUSTER or VACUUM
1724 : : * FULL.
1725 : : *
1726 : : * Additional Input parameters:
1727 : : * - use_sort - if true, the table contents are sorted appropriate for
1728 : : * `OldIndex`; if false and OldIndex is not InvalidOid, the data is copied
1729 : : * in that index's order; if false and OldIndex is InvalidOid, no sorting is
1730 : : * performed
1731 : : * - OldIndex - see use_sort
1732 : : * - OldestXmin - computed by vacuum_get_cutoffs(), even when
1733 : : * not needed for the relation's AM
1734 : : * - *xid_cutoff - ditto
1735 : : * - *multi_cutoff - ditto
1736 : : * - snapshot - if != NULL, ignore data changes done by transactions that this
1737 : : * (MVCC) snapshot considers still in-progress or in the future.
1738 : : *
1739 : : * Output parameters:
1740 : : * - *xid_cutoff - rel's new relfrozenxid value, may be invalid
1741 : : * - *multi_cutoff - rel's new relminmxid value, may be invalid
1742 : : * - *tups_vacuumed - stats, for logging, if appropriate for AM
1743 : : * - *tups_recently_dead - stats, for logging, if appropriate for AM
1744 : : */
1745 : : static inline void
1746 : 408 : table_relation_copy_for_cluster(Relation OldTable, Relation NewTable,
1747 : : Relation OldIndex,
1748 : : bool use_sort,
1749 : : TransactionId OldestXmin,
1750 : : Snapshot snapshot,
1751 : : TransactionId *xid_cutoff,
1752 : : MultiXactId *multi_cutoff,
1753 : : double *num_tuples,
1754 : : double *tups_vacuumed,
1755 : : double *tups_recently_dead)
1756 : : {
1757 : 408 : OldTable->rd_tableam->relation_copy_for_cluster(OldTable, NewTable, OldIndex,
1758 : : use_sort, OldestXmin,
1759 : : snapshot,
1760 : : xid_cutoff, multi_cutoff,
1761 : : num_tuples, tups_vacuumed,
1762 : : tups_recently_dead);
1763 : 408 : }
1764 : :
1765 : : /*
1766 : : * Perform VACUUM on the relation. The VACUUM can be triggered by a user or by
1767 : : * autovacuum. The specific actions performed by the AM will depend heavily on
1768 : : * the individual AM.
1769 : : *
1770 : : * On entry a transaction needs to already been established, and the
1771 : : * table is locked with a ShareUpdateExclusive lock.
1772 : : *
1773 : : * Note that neither VACUUM FULL (and CLUSTER), nor ANALYZE go through this
1774 : : * routine, even if (for ANALYZE) it is part of the same VACUUM command.
1775 : : */
1776 : : static inline void
1777 : 129726 : table_relation_vacuum(Relation rel, const VacuumParams *params,
1778 : : BufferAccessStrategy bstrategy)
1779 : : {
1780 : 129726 : rel->rd_tableam->relation_vacuum(rel, params, bstrategy);
1781 : 129725 : }
1782 : :
1783 : : /*
1784 : : * Prepare to analyze the next block in the read stream. The scan needs to
1785 : : * have been started with table_beginscan_analyze(). Note that this routine
1786 : : * might acquire resources like locks that are held until
1787 : : * table_scan_analyze_next_tuple() returns false.
1788 : : *
1789 : : * Returns false if block is unsuitable for sampling, true otherwise.
1790 : : */
1791 : : static inline bool
1792 : 91650 : table_scan_analyze_next_block(TableScanDesc scan, ReadStream *stream)
1793 : : {
1794 : 91650 : return scan->rs_rd->rd_tableam->scan_analyze_next_block(scan, stream);
1795 : : }
1796 : :
1797 : : /*
1798 : : * Iterate over tuples in the block selected with
1799 : : * table_scan_analyze_next_block() (which needs to have returned true, and
1800 : : * this routine may not have returned false for the same block before). If a
1801 : : * tuple that's suitable for sampling is found, true is returned and a tuple
1802 : : * is stored in `slot`.
1803 : : *
1804 : : * *liverows and *deadrows are incremented according to the encountered
1805 : : * tuples.
1806 : : */
1807 : : static inline bool
1808 : 7254105 : table_scan_analyze_next_tuple(TableScanDesc scan,
1809 : : double *liverows, double *deadrows,
1810 : : TupleTableSlot *slot)
1811 : : {
1812 : 7254105 : return scan->rs_rd->rd_tableam->scan_analyze_next_tuple(scan,
1813 : : liverows, deadrows,
1814 : : slot);
1815 : : }
1816 : :
1817 : : /*
1818 : : * table_index_build_scan - scan the table to find tuples to be indexed
1819 : : *
1820 : : * This is called back from an access-method-specific index build procedure
1821 : : * after the AM has done whatever setup it needs. The parent table relation
1822 : : * is scanned to find tuples that should be entered into the index. Each
1823 : : * such tuple is passed to the AM's callback routine, which does the right
1824 : : * things to add it to the new index. After we return, the AM's index
1825 : : * build procedure does whatever cleanup it needs.
1826 : : *
1827 : : * The total count of live tuples is returned. This is for updating pg_class
1828 : : * statistics. (It's annoying not to be able to do that here, but we want to
1829 : : * merge that update with others; see index_update_stats.) Note that the
1830 : : * index AM itself must keep track of the number of index tuples; we don't do
1831 : : * so here because the AM might reject some of the tuples for its own reasons,
1832 : : * such as being unable to store NULLs.
1833 : : *
1834 : : * If 'progress', the PROGRESS_SCAN_BLOCKS_TOTAL counter is updated when
1835 : : * starting the scan, and PROGRESS_SCAN_BLOCKS_DONE is updated as we go along.
1836 : : *
1837 : : * A side effect is to set indexInfo->ii_BrokenHotChain to true if we detect
1838 : : * any potentially broken HOT chains. Currently, we set this if there are any
1839 : : * RECENTLY_DEAD or DELETE_IN_PROGRESS entries in a HOT chain, without trying
1840 : : * very hard to detect whether they're really incompatible with the chain tip.
1841 : : * This only really makes sense for heap AM, it might need to be generalized
1842 : : * for other AMs later.
1843 : : */
1844 : : static inline double
1845 : 35060 : table_index_build_scan(Relation table_rel,
1846 : : Relation index_rel,
1847 : : IndexInfo *index_info,
1848 : : bool allow_sync,
1849 : : bool progress,
1850 : : IndexBuildCallback callback,
1851 : : void *callback_state,
1852 : : TableScanDesc scan)
1853 : : {
1854 : 35060 : return table_rel->rd_tableam->index_build_range_scan(table_rel,
1855 : : index_rel,
1856 : : index_info,
1857 : : allow_sync,
1858 : : false,
1859 : : progress,
1860 : : 0,
1861 : : InvalidBlockNumber,
1862 : : callback,
1863 : : callback_state,
1864 : : scan);
1865 : : }
1866 : :
1867 : : /*
1868 : : * As table_index_build_scan(), except that instead of scanning the complete
1869 : : * table, only the given number of blocks are scanned. Scan to end-of-rel can
1870 : : * be signaled by passing InvalidBlockNumber as numblocks. Note that
1871 : : * restricting the range to scan cannot be done when requesting syncscan.
1872 : : *
1873 : : * When "anyvisible" mode is requested, all tuples visible to any transaction
1874 : : * are indexed and counted as live, including those inserted or deleted by
1875 : : * transactions that are still in progress.
1876 : : */
1877 : : static inline double
1878 : 1492 : table_index_build_range_scan(Relation table_rel,
1879 : : Relation index_rel,
1880 : : IndexInfo *index_info,
1881 : : bool allow_sync,
1882 : : bool anyvisible,
1883 : : bool progress,
1884 : : BlockNumber start_blockno,
1885 : : BlockNumber numblocks,
1886 : : IndexBuildCallback callback,
1887 : : void *callback_state,
1888 : : TableScanDesc scan)
1889 : : {
1890 : 1492 : return table_rel->rd_tableam->index_build_range_scan(table_rel,
1891 : : index_rel,
1892 : : index_info,
1893 : : allow_sync,
1894 : : anyvisible,
1895 : : progress,
1896 : : start_blockno,
1897 : : numblocks,
1898 : : callback,
1899 : : callback_state,
1900 : : scan);
1901 : : }
1902 : :
1903 : : /*
1904 : : * table_index_validate_scan - second table scan for concurrent index build
1905 : : *
1906 : : * See validate_index() for an explanation.
1907 : : */
1908 : : static inline void
1909 : 431 : table_index_validate_scan(Relation table_rel,
1910 : : Relation index_rel,
1911 : : IndexInfo *index_info,
1912 : : Snapshot snapshot,
1913 : : ValidateIndexState *state)
1914 : : {
1915 : 431 : table_rel->rd_tableam->index_validate_scan(table_rel,
1916 : : index_rel,
1917 : : index_info,
1918 : : snapshot,
1919 : : state);
1920 : 431 : }
1921 : :
1922 : :
1923 : : /* ----------------------------------------------------------------------------
1924 : : * Miscellaneous functionality
1925 : : * ----------------------------------------------------------------------------
1926 : : */
1927 : :
1928 : : /*
1929 : : * Return the current size of `rel` in bytes. If `forkNumber` is
1930 : : * InvalidForkNumber, return the relation's overall size, otherwise the size
1931 : : * for the indicated fork.
1932 : : *
1933 : : * Note that the overall size might not be the equivalent of the sum of sizes
1934 : : * for the individual forks for some AMs, e.g. because the AMs storage does
1935 : : * not neatly map onto the builtin types of forks.
1936 : : */
1937 : : static inline uint64
1938 : 1706386 : table_relation_size(Relation rel, ForkNumber forkNumber)
1939 : : {
1940 : 1706386 : return rel->rd_tableam->relation_size(rel, forkNumber);
1941 : : }
1942 : :
1943 : : /*
1944 : : * table_relation_needs_toast_table - does this relation need a toast table?
1945 : : */
1946 : : static inline bool
1947 : 31376 : table_relation_needs_toast_table(Relation rel)
1948 : : {
1949 : 31376 : return rel->rd_tableam->relation_needs_toast_table(rel);
1950 : : }
1951 : :
1952 : : /*
1953 : : * Return the OID of the AM that should be used to implement the TOAST table
1954 : : * for this relation.
1955 : : */
1956 : : static inline Oid
1957 : 11524 : table_relation_toast_am(Relation rel)
1958 : : {
1959 : 11524 : return rel->rd_tableam->relation_toast_am(rel);
1960 : : }
1961 : :
1962 : : /*
1963 : : * Fetch all or part of a TOAST value from a TOAST table.
1964 : : *
1965 : : * If this AM is never used to implement a TOAST table, then this callback
1966 : : * is not needed. But, if toasted values are ever stored in a table of this
1967 : : * type, then you will need this callback.
1968 : : *
1969 : : * toastrel is the relation in which the toasted value is stored.
1970 : : *
1971 : : * valueid identifies which toast value is to be fetched. For the heap,
1972 : : * this corresponds to the values stored in the chunk_id column.
1973 : : *
1974 : : * attrsize is the total size of the toast value to be fetched.
1975 : : *
1976 : : * sliceoffset is the offset within the toast value of the first byte that
1977 : : * should be fetched.
1978 : : *
1979 : : * slicelength is the number of bytes from the toast value that should be
1980 : : * fetched.
1981 : : *
1982 : : * result is caller-allocated space into which the fetched bytes should be
1983 : : * stored.
1984 : : */
1985 : : static inline void
1986 : 17451 : table_relation_fetch_toast_slice(Relation toastrel, Oid valueid,
1987 : : int32 attrsize, int32 sliceoffset,
1988 : : int32 slicelength, varlena *result)
1989 : : {
1990 : 17451 : toastrel->rd_tableam->relation_fetch_toast_slice(toastrel, valueid,
1991 : : attrsize,
1992 : : sliceoffset, slicelength,
1993 : : result);
1994 : 17451 : }
1995 : :
1996 : :
1997 : : /* ----------------------------------------------------------------------------
1998 : : * Planner related functionality
1999 : : * ----------------------------------------------------------------------------
2000 : : */
2001 : :
2002 : : /*
2003 : : * Estimate the current size of the relation, as an AM specific workhorse for
2004 : : * estimate_rel_size(). Look there for an explanation of the parameters.
2005 : : */
2006 : : static inline void
2007 : 346472 : table_relation_estimate_size(Relation rel, int32 *attr_widths,
2008 : : BlockNumber *pages, double *tuples,
2009 : : double *allvisfrac)
2010 : : {
2011 : 346472 : rel->rd_tableam->relation_estimate_size(rel, attr_widths, pages, tuples,
2012 : : allvisfrac);
2013 : 346472 : }
2014 : :
2015 : :
2016 : : /* ----------------------------------------------------------------------------
2017 : : * Executor related functionality
2018 : : * ----------------------------------------------------------------------------
2019 : : */
2020 : :
2021 : : /*
2022 : : * Fetch / check / return tuples as part of a bitmap table scan. `scan` needs
2023 : : * to have been started via table_beginscan_bm(). Fetch the next tuple of a
2024 : : * bitmap table scan into `slot` and return true if a visible tuple was found,
2025 : : * false otherwise.
2026 : : *
2027 : : * `recheck` is set by the table AM to indicate whether or not the tuple in
2028 : : * `slot` should be rechecked. Tuples from lossy pages will always need to be
2029 : : * rechecked, but some non-lossy pages' tuples may also require recheck.
2030 : : *
2031 : : * `lossy_pages` is incremented if the block's representation in the bitmap is
2032 : : * lossy; otherwise, `exact_pages` is incremented.
2033 : : */
2034 : : static inline bool
2035 : 4062809 : table_scan_bitmap_next_tuple(TableScanDesc scan,
2036 : : TupleTableSlot *slot,
2037 : : bool *recheck,
2038 : : uint64 *lossy_pages,
2039 : : uint64 *exact_pages)
2040 : : {
2041 : 4062809 : return scan->rs_rd->rd_tableam->scan_bitmap_next_tuple(scan,
2042 : : slot,
2043 : : recheck,
2044 : : lossy_pages,
2045 : : exact_pages);
2046 : : }
2047 : :
2048 : : /*
2049 : : * Prepare to fetch tuples from the next block in a sample scan. Returns false
2050 : : * if the sample scan is finished, true otherwise. `scan` needs to have been
2051 : : * started via table_beginscan_sampling().
2052 : : *
2053 : : * This will call the TsmRoutine's NextSampleBlock() callback if necessary
2054 : : * (i.e. NextSampleBlock is not NULL), or perform a sequential scan over the
2055 : : * underlying relation.
2056 : : */
2057 : : static inline bool
2058 : 8587 : table_scan_sample_next_block(TableScanDesc scan,
2059 : : SampleScanState *scanstate)
2060 : : {
2061 : 8587 : return scan->rs_rd->rd_tableam->scan_sample_next_block(scan, scanstate);
2062 : : }
2063 : :
2064 : : /*
2065 : : * Fetch the next sample tuple into `slot` and return true if a visible tuple
2066 : : * was found, false otherwise. table_scan_sample_next_block() needs to
2067 : : * previously have selected a block (i.e. returned true), and no previous
2068 : : * table_scan_sample_next_tuple() for the same block may have returned false.
2069 : : *
2070 : : * This will call the TsmRoutine's NextSampleTuple() callback.
2071 : : */
2072 : : static inline bool
2073 : 169182 : table_scan_sample_next_tuple(TableScanDesc scan,
2074 : : SampleScanState *scanstate,
2075 : : TupleTableSlot *slot)
2076 : : {
2077 : 169182 : return scan->rs_rd->rd_tableam->scan_sample_next_tuple(scan, scanstate,
2078 : : slot);
2079 : : }
2080 : :
2081 : :
2082 : : /* ----------------------------------------------------------------------------
2083 : : * Functions to make modifications a bit simpler.
2084 : : * ----------------------------------------------------------------------------
2085 : : */
2086 : :
2087 : : extern void simple_table_tuple_insert(Relation rel, TupleTableSlot *slot);
2088 : : extern void simple_table_tuple_delete(Relation rel, ItemPointer tid,
2089 : : Snapshot snapshot);
2090 : : extern void simple_table_tuple_update(Relation rel, ItemPointer otid,
2091 : : TupleTableSlot *slot, Snapshot snapshot,
2092 : : TU_UpdateIndexes *update_indexes);
2093 : :
2094 : :
2095 : : /* ----------------------------------------------------------------------------
2096 : : * Helper functions to implement parallel scans for block oriented AMs.
2097 : : * ----------------------------------------------------------------------------
2098 : : */
2099 : :
2100 : : extern Size table_block_parallelscan_estimate(Relation rel);
2101 : : extern Size table_block_parallelscan_initialize(Relation rel,
2102 : : ParallelTableScanDesc pscan);
2103 : : extern void table_block_parallelscan_reinitialize(Relation rel,
2104 : : ParallelTableScanDesc pscan);
2105 : : extern BlockNumber table_block_parallelscan_nextpage(Relation rel,
2106 : : ParallelBlockTableScanWorker pbscanwork,
2107 : : ParallelBlockTableScanDesc pbscan);
2108 : : extern void table_block_parallelscan_startblock_init(Relation rel,
2109 : : ParallelBlockTableScanWorker pbscanwork,
2110 : : ParallelBlockTableScanDesc pbscan,
2111 : : BlockNumber startblock,
2112 : : BlockNumber numblocks);
2113 : :
2114 : :
2115 : : /* ----------------------------------------------------------------------------
2116 : : * Helper functions to implement relation sizing for block oriented AMs.
2117 : : * ----------------------------------------------------------------------------
2118 : : */
2119 : :
2120 : : extern uint64 table_block_relation_size(Relation rel, ForkNumber forkNumber);
2121 : : extern void table_block_relation_estimate_size(Relation rel,
2122 : : int32 *attr_widths,
2123 : : BlockNumber *pages,
2124 : : double *tuples,
2125 : : double *allvisfrac,
2126 : : Size overhead_bytes_per_tuple,
2127 : : Size usable_bytes_per_page);
2128 : :
2129 : : /* ----------------------------------------------------------------------------
2130 : : * Functions in tableamapi.c
2131 : : * ----------------------------------------------------------------------------
2132 : : */
2133 : :
2134 : : extern const TableAmRoutine *GetTableAmRoutine(Oid amhandler);
2135 : :
2136 : : /* ----------------------------------------------------------------------------
2137 : : * Functions in heapam_handler.c
2138 : : * ----------------------------------------------------------------------------
2139 : : */
2140 : :
2141 : : extern const TableAmRoutine *GetHeapamTableAmRoutine(void);
2142 : :
2143 : : #endif /* TABLEAM_H */
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