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1 : /*-------------------------------------------------------------------------
2 : *
3 : * tableam.h
4 : * POSTGRES table access method definitions.
5 : *
6 : *
7 : * Portions Copyright (c) 1996-2024, 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 : struct BulkInsertStateData;
37 : struct IndexInfo;
38 : struct SampleScanState;
39 : struct VacuumParams;
40 : struct ValidateIndexState;
41 :
42 : /*
43 : * Bitmask values for the flags argument to the scan_begin callback.
44 : */
45 : typedef enum ScanOptions
46 : {
47 : /* one of SO_TYPE_* may be specified */
48 : SO_TYPE_SEQSCAN = 1 << 0,
49 : SO_TYPE_BITMAPSCAN = 1 << 1,
50 : SO_TYPE_SAMPLESCAN = 1 << 2,
51 : SO_TYPE_TIDSCAN = 1 << 3,
52 : SO_TYPE_TIDRANGESCAN = 1 << 4,
53 : SO_TYPE_ANALYZE = 1 << 5,
54 :
55 : /* several of SO_ALLOW_* may be specified */
56 : /* allow or disallow use of access strategy */
57 : SO_ALLOW_STRAT = 1 << 6,
58 : /* report location to syncscan logic? */
59 : SO_ALLOW_SYNC = 1 << 7,
60 : /* verify visibility page-at-a-time? */
61 : SO_ALLOW_PAGEMODE = 1 << 8,
62 :
63 : /* unregister snapshot at scan end? */
64 : SO_TEMP_SNAPSHOT = 1 << 9,
65 :
66 : /*
67 : * At the discretion of the table AM, bitmap table scans may be able to
68 : * skip fetching a block from the table if none of the table data is
69 : * needed. If table data may be needed, set SO_NEED_TUPLES.
70 : */
71 : SO_NEED_TUPLES = 1 << 10,
72 : } ScanOptions;
73 :
74 : /*
75 : * Result codes for table_{update,delete,lock_tuple}, and for visibility
76 : * routines inside table AMs.
77 : */
78 : typedef enum TM_Result
79 : {
80 : /*
81 : * Signals that the action succeeded (i.e. update/delete performed, lock
82 : * was acquired)
83 : */
84 : TM_Ok,
85 :
86 : /* The affected tuple wasn't visible to the relevant snapshot */
87 : TM_Invisible,
88 :
89 : /* The affected tuple was already modified by the calling backend */
90 : TM_SelfModified,
91 :
92 : /*
93 : * The affected tuple was updated by another transaction. This includes
94 : * the case where tuple was moved to another partition.
95 : */
96 : TM_Updated,
97 :
98 : /* The affected tuple was deleted by another transaction */
99 : TM_Deleted,
100 :
101 : /*
102 : * The affected tuple is currently being modified by another session. This
103 : * will only be returned if table_(update/delete/lock_tuple) are
104 : * instructed not to wait.
105 : */
106 : TM_BeingModified,
107 :
108 : /* lock couldn't be acquired, action skipped. Only used by lock_tuple */
109 : TM_WouldBlock,
110 : } TM_Result;
111 :
112 : /*
113 : * Result codes for table_update(..., update_indexes*..).
114 : * Used to determine which indexes to update.
115 : */
116 : typedef enum TU_UpdateIndexes
117 : {
118 : /* No indexed columns were updated (incl. TID addressing of tuple) */
119 : TU_None,
120 :
121 : /* A non-summarizing indexed column was updated, or the TID has changed */
122 : TU_All,
123 :
124 : /* Only summarized columns were updated, TID is unchanged */
125 : TU_Summarizing,
126 : } TU_UpdateIndexes;
127 :
128 : /*
129 : * When table_tuple_update, table_tuple_delete, or table_tuple_lock fail
130 : * because the target tuple is already outdated, they fill in this struct to
131 : * provide information to the caller about what happened.
132 : *
133 : * ctid is the target's ctid link: it is the same as the target's TID if the
134 : * target was deleted, or the location of the replacement tuple if the target
135 : * was updated.
136 : *
137 : * xmax is the outdating transaction's XID. If the caller wants to visit the
138 : * replacement tuple, it must check that this matches before believing the
139 : * replacement is really a match.
140 : *
141 : * cmax is the outdating command's CID, but only when the failure code is
142 : * TM_SelfModified (i.e., something in the current transaction outdated the
143 : * tuple); otherwise cmax is zero. (We make this restriction because
144 : * HeapTupleHeaderGetCmax doesn't work for tuples outdated in other
145 : * transactions.)
146 : */
147 : typedef struct TM_FailureData
148 : {
149 : ItemPointerData ctid;
150 : TransactionId xmax;
151 : CommandId cmax;
152 : bool traversed;
153 : } TM_FailureData;
154 :
155 : /*
156 : * State used when calling table_index_delete_tuples().
157 : *
158 : * Represents the status of table tuples, referenced by table TID and taken by
159 : * index AM from index tuples. State consists of high level parameters of the
160 : * deletion operation, plus two mutable palloc()'d arrays for information
161 : * about the status of individual table tuples. These are conceptually one
162 : * single array. Using two arrays keeps the TM_IndexDelete struct small,
163 : * which makes sorting the first array (the deltids array) fast.
164 : *
165 : * Some index AM callers perform simple index tuple deletion (by specifying
166 : * bottomup = false), and include only known-dead deltids. These known-dead
167 : * entries are all marked knowndeletable = true directly (typically these are
168 : * TIDs from LP_DEAD-marked index tuples), but that isn't strictly required.
169 : *
170 : * Callers that specify bottomup = true are "bottom-up index deletion"
171 : * callers. The considerations for the tableam are more subtle with these
172 : * callers because they ask the tableam to perform highly speculative work,
173 : * and might only expect the tableam to check a small fraction of all entries.
174 : * Caller is not allowed to specify knowndeletable = true for any entry
175 : * because everything is highly speculative. Bottom-up caller provides
176 : * context and hints to tableam -- see comments below for details on how index
177 : * AMs and tableams should coordinate during bottom-up index deletion.
178 : *
179 : * Simple index deletion callers may ask the tableam to perform speculative
180 : * work, too. This is a little like bottom-up deletion, but not too much.
181 : * The tableam will only perform speculative work when it's practically free
182 : * to do so in passing for simple deletion caller (while always performing
183 : * whatever work is needed to enable knowndeletable/LP_DEAD index tuples to
184 : * be deleted within index AM). This is the real reason why it's possible for
185 : * simple index deletion caller to specify knowndeletable = false up front
186 : * (this means "check if it's possible for me to delete corresponding index
187 : * tuple when it's cheap to do so in passing"). The index AM should only
188 : * include "extra" entries for index tuples whose TIDs point to a table block
189 : * that tableam is expected to have to visit anyway (in the event of a block
190 : * orientated tableam). The tableam isn't strictly obligated to check these
191 : * "extra" TIDs, but a block-based AM should always manage to do so in
192 : * practice.
193 : *
194 : * The final contents of the deltids/status arrays are interesting to callers
195 : * that ask tableam to perform speculative work (i.e. when _any_ items have
196 : * knowndeletable set to false up front). These index AM callers will
197 : * naturally need to consult final state to determine which index tuples are
198 : * in fact deletable.
199 : *
200 : * The index AM can keep track of which index tuple relates to which deltid by
201 : * setting idxoffnum (and/or relying on each entry being uniquely identifiable
202 : * using tid), which is important when the final contents of the array will
203 : * need to be interpreted -- the array can shrink from initial size after
204 : * tableam processing and/or have entries in a new order (tableam may sort
205 : * deltids array for its own reasons). Bottom-up callers may find that final
206 : * ndeltids is 0 on return from call to tableam, in which case no index tuple
207 : * deletions are possible. Simple deletion callers can rely on any entries
208 : * they know to be deletable appearing in the final array as deletable.
209 : */
210 : typedef struct TM_IndexDelete
211 : {
212 : ItemPointerData tid; /* table TID from index tuple */
213 : int16 id; /* Offset into TM_IndexStatus array */
214 : } TM_IndexDelete;
215 :
216 : typedef struct TM_IndexStatus
217 : {
218 : OffsetNumber idxoffnum; /* Index am page offset number */
219 : bool knowndeletable; /* Currently known to be deletable? */
220 :
221 : /* Bottom-up index deletion specific fields follow */
222 : bool promising; /* Promising (duplicate) index tuple? */
223 : int16 freespace; /* Space freed in index if deleted */
224 : } TM_IndexStatus;
225 :
226 : /*
227 : * Index AM/tableam coordination is central to the design of bottom-up index
228 : * deletion. The index AM provides hints about where to look to the tableam
229 : * by marking some entries as "promising". Index AM does this with duplicate
230 : * index tuples that are strongly suspected to be old versions left behind by
231 : * UPDATEs that did not logically modify indexed values. Index AM may find it
232 : * helpful to only mark entries as promising when they're thought to have been
233 : * affected by such an UPDATE in the recent past.
234 : *
235 : * Bottom-up index deletion casts a wide net at first, usually by including
236 : * all TIDs on a target index page. It is up to the tableam to worry about
237 : * the cost of checking transaction status information. The tableam is in
238 : * control, but needs careful guidance from the index AM. Index AM requests
239 : * that bottomupfreespace target be met, while tableam measures progress
240 : * towards that goal by tallying the per-entry freespace value for known
241 : * deletable entries. (All !bottomup callers can just set these space related
242 : * fields to zero.)
243 : */
244 : typedef struct TM_IndexDeleteOp
245 : {
246 : Relation irel; /* Target index relation */
247 : BlockNumber iblknum; /* Index block number (for error reports) */
248 : bool bottomup; /* Bottom-up (not simple) deletion? */
249 : int bottomupfreespace; /* Bottom-up space target */
250 :
251 : /* Mutable per-TID information follows (index AM initializes entries) */
252 : int ndeltids; /* Current # of deltids/status elements */
253 : TM_IndexDelete *deltids;
254 : TM_IndexStatus *status;
255 : } TM_IndexDeleteOp;
256 :
257 : /* "options" flag bits for table_tuple_insert */
258 : /* TABLE_INSERT_SKIP_WAL was 0x0001; RelationNeedsWAL() now governs */
259 : #define TABLE_INSERT_SKIP_FSM 0x0002
260 : #define TABLE_INSERT_FROZEN 0x0004
261 : #define TABLE_INSERT_NO_LOGICAL 0x0008
262 :
263 : /* flag bits for table_tuple_lock */
264 : /* Follow tuples whose update is in progress if lock modes don't conflict */
265 : #define TUPLE_LOCK_FLAG_LOCK_UPDATE_IN_PROGRESS (1 << 0)
266 : /* Follow update chain and lock latest version of tuple */
267 : #define TUPLE_LOCK_FLAG_FIND_LAST_VERSION (1 << 1)
268 :
269 :
270 : /* Typedef for callback function for table_index_build_scan */
271 : typedef void (*IndexBuildCallback) (Relation index,
272 : ItemPointer tid,
273 : Datum *values,
274 : bool *isnull,
275 : bool tupleIsAlive,
276 : void *state);
277 :
278 : /*
279 : * API struct for a table AM. Note this must be allocated in a
280 : * server-lifetime manner, typically as a static const struct, which then gets
281 : * returned by FormData_pg_am.amhandler.
282 : *
283 : * In most cases it's not appropriate to call the callbacks directly, use the
284 : * table_* wrapper functions instead.
285 : *
286 : * GetTableAmRoutine() asserts that required callbacks are filled in, remember
287 : * to update when adding a callback.
288 : */
289 : typedef struct TableAmRoutine
290 : {
291 : /* this must be set to T_TableAmRoutine */
292 : NodeTag type;
293 :
294 :
295 : /* ------------------------------------------------------------------------
296 : * Slot related callbacks.
297 : * ------------------------------------------------------------------------
298 : */
299 :
300 : /*
301 : * Return slot implementation suitable for storing a tuple of this AM.
302 : */
303 : const TupleTableSlotOps *(*slot_callbacks) (Relation rel);
304 :
305 :
306 : /* ------------------------------------------------------------------------
307 : * Table scan callbacks.
308 : * ------------------------------------------------------------------------
309 : */
310 :
311 : /*
312 : * Start a scan of `rel`. The callback has to return a TableScanDesc,
313 : * which will typically be embedded in a larger, AM specific, struct.
314 : *
315 : * If nkeys != 0, the results need to be filtered by those scan keys.
316 : *
317 : * pscan, if not NULL, will have already been initialized with
318 : * parallelscan_initialize(), and has to be for the same relation. Will
319 : * only be set coming from table_beginscan_parallel().
320 : *
321 : * `flags` is a bitmask indicating the type of scan (ScanOptions's
322 : * SO_TYPE_*, currently only one may be specified), options controlling
323 : * the scan's behaviour (ScanOptions's SO_ALLOW_*, several may be
324 : * specified, an AM may ignore unsupported ones) and whether the snapshot
325 : * needs to be deallocated at scan_end (ScanOptions's SO_TEMP_SNAPSHOT).
326 : */
327 : TableScanDesc (*scan_begin) (Relation rel,
328 : Snapshot snapshot,
329 : int nkeys, struct ScanKeyData *key,
330 : ParallelTableScanDesc pscan,
331 : uint32 flags);
332 :
333 : /*
334 : * Release resources and deallocate scan. If TableScanDesc.temp_snap,
335 : * TableScanDesc.rs_snapshot needs to be unregistered.
336 : */
337 : void (*scan_end) (TableScanDesc scan);
338 :
339 : /*
340 : * Restart relation scan. If set_params is set to true, allow_{strat,
341 : * sync, pagemode} (see scan_begin) changes should be taken into account.
342 : */
343 : void (*scan_rescan) (TableScanDesc scan, struct ScanKeyData *key,
344 : bool set_params, bool allow_strat,
345 : bool allow_sync, bool allow_pagemode);
346 :
347 : /*
348 : * Return next tuple from `scan`, store in slot.
349 : */
350 : bool (*scan_getnextslot) (TableScanDesc scan,
351 : ScanDirection direction,
352 : TupleTableSlot *slot);
353 :
354 : /*-----------
355 : * Optional functions to provide scanning for ranges of ItemPointers.
356 : * Implementations must either provide both of these functions, or neither
357 : * of them.
358 : *
359 : * Implementations of scan_set_tidrange must themselves handle
360 : * ItemPointers of any value. i.e, they must handle each of the following:
361 : *
362 : * 1) mintid or maxtid is beyond the end of the table; and
363 : * 2) mintid is above maxtid; and
364 : * 3) item offset for mintid or maxtid is beyond the maximum offset
365 : * allowed by the AM.
366 : *
367 : * Implementations can assume that scan_set_tidrange is always called
368 : * before scan_getnextslot_tidrange or after scan_rescan and before any
369 : * further calls to scan_getnextslot_tidrange.
370 : */
371 : void (*scan_set_tidrange) (TableScanDesc scan,
372 : ItemPointer mintid,
373 : ItemPointer maxtid);
374 :
375 : /*
376 : * Return next tuple from `scan` that's in the range of TIDs defined by
377 : * scan_set_tidrange.
378 : */
379 : bool (*scan_getnextslot_tidrange) (TableScanDesc scan,
380 : ScanDirection direction,
381 : TupleTableSlot *slot);
382 :
383 : /* ------------------------------------------------------------------------
384 : * Parallel table scan related functions.
385 : * ------------------------------------------------------------------------
386 : */
387 :
388 : /*
389 : * Estimate the size of shared memory needed for a parallel scan of this
390 : * relation. The snapshot does not need to be accounted for.
391 : */
392 : Size (*parallelscan_estimate) (Relation rel);
393 :
394 : /*
395 : * Initialize ParallelTableScanDesc for a parallel scan of this relation.
396 : * `pscan` will be sized according to parallelscan_estimate() for the same
397 : * relation.
398 : */
399 : Size (*parallelscan_initialize) (Relation rel,
400 : ParallelTableScanDesc pscan);
401 :
402 : /*
403 : * Reinitialize `pscan` for a new scan. `rel` will be the same relation as
404 : * when `pscan` was initialized by parallelscan_initialize.
405 : */
406 : void (*parallelscan_reinitialize) (Relation rel,
407 : ParallelTableScanDesc pscan);
408 :
409 :
410 : /* ------------------------------------------------------------------------
411 : * Index Scan Callbacks
412 : * ------------------------------------------------------------------------
413 : */
414 :
415 : /*
416 : * Prepare to fetch tuples from the relation, as needed when fetching
417 : * tuples for an index scan. The callback has to return an
418 : * IndexFetchTableData, which the AM will typically embed in a larger
419 : * structure with additional information.
420 : *
421 : * Tuples for an index scan can then be fetched via index_fetch_tuple.
422 : */
423 : struct IndexFetchTableData *(*index_fetch_begin) (Relation rel);
424 :
425 : /*
426 : * Reset index fetch. Typically this will release cross index fetch
427 : * resources held in IndexFetchTableData.
428 : */
429 : void (*index_fetch_reset) (struct IndexFetchTableData *data);
430 :
431 : /*
432 : * Release resources and deallocate index fetch.
433 : */
434 : void (*index_fetch_end) (struct IndexFetchTableData *data);
435 :
436 : /*
437 : * Fetch tuple at `tid` into `slot`, after doing a visibility test
438 : * according to `snapshot`. If a tuple was found and passed the visibility
439 : * test, return true, false otherwise.
440 : *
441 : * Note that AMs that do not necessarily update indexes when indexed
442 : * columns do not change, need to return the current/correct version of
443 : * the tuple that is visible to the snapshot, even if the tid points to an
444 : * older version of the tuple.
445 : *
446 : * *call_again is false on the first call to index_fetch_tuple for a tid.
447 : * If there potentially is another tuple matching the tid, *call_again
448 : * needs to be set to true by index_fetch_tuple, signaling to the caller
449 : * that index_fetch_tuple should be called again for the same tid.
450 : *
451 : * *all_dead, if all_dead is not NULL, should be set to true by
452 : * index_fetch_tuple iff it is guaranteed that no backend needs to see
453 : * that tuple. Index AMs can use that to avoid returning that tid in
454 : * future searches.
455 : */
456 : bool (*index_fetch_tuple) (struct IndexFetchTableData *scan,
457 : ItemPointer tid,
458 : Snapshot snapshot,
459 : TupleTableSlot *slot,
460 : bool *call_again, bool *all_dead);
461 :
462 :
463 : /* ------------------------------------------------------------------------
464 : * Callbacks for non-modifying operations on individual tuples
465 : * ------------------------------------------------------------------------
466 : */
467 :
468 : /*
469 : * Fetch tuple at `tid` into `slot`, after doing a visibility test
470 : * according to `snapshot`. If a tuple was found and passed the visibility
471 : * test, returns true, false otherwise.
472 : */
473 : bool (*tuple_fetch_row_version) (Relation rel,
474 : ItemPointer tid,
475 : Snapshot snapshot,
476 : TupleTableSlot *slot);
477 :
478 : /*
479 : * Is tid valid for a scan of this relation.
480 : */
481 : bool (*tuple_tid_valid) (TableScanDesc scan,
482 : ItemPointer tid);
483 :
484 : /*
485 : * Return the latest version of the tuple at `tid`, by updating `tid` to
486 : * point at the newest version.
487 : */
488 : void (*tuple_get_latest_tid) (TableScanDesc scan,
489 : ItemPointer tid);
490 :
491 : /*
492 : * Does the tuple in `slot` satisfy `snapshot`? The slot needs to be of
493 : * the appropriate type for the AM.
494 : */
495 : bool (*tuple_satisfies_snapshot) (Relation rel,
496 : TupleTableSlot *slot,
497 : Snapshot snapshot);
498 :
499 : /* see table_index_delete_tuples() */
500 : TransactionId (*index_delete_tuples) (Relation rel,
501 : TM_IndexDeleteOp *delstate);
502 :
503 :
504 : /* ------------------------------------------------------------------------
505 : * Manipulations of physical tuples.
506 : * ------------------------------------------------------------------------
507 : */
508 :
509 : /* see table_tuple_insert() for reference about parameters */
510 : void (*tuple_insert) (Relation rel, TupleTableSlot *slot,
511 : CommandId cid, int options,
512 : struct BulkInsertStateData *bistate);
513 :
514 : /* see table_tuple_insert_speculative() for reference about parameters */
515 : void (*tuple_insert_speculative) (Relation rel,
516 : TupleTableSlot *slot,
517 : CommandId cid,
518 : int options,
519 : struct BulkInsertStateData *bistate,
520 : uint32 specToken);
521 :
522 : /* see table_tuple_complete_speculative() for reference about parameters */
523 : void (*tuple_complete_speculative) (Relation rel,
524 : TupleTableSlot *slot,
525 : uint32 specToken,
526 : bool succeeded);
527 :
528 : /* see table_multi_insert() for reference about parameters */
529 : void (*multi_insert) (Relation rel, TupleTableSlot **slots, int nslots,
530 : CommandId cid, int options, struct BulkInsertStateData *bistate);
531 :
532 : /* see table_tuple_delete() for reference about parameters */
533 : TM_Result (*tuple_delete) (Relation rel,
534 : ItemPointer tid,
535 : CommandId cid,
536 : Snapshot snapshot,
537 : Snapshot crosscheck,
538 : bool wait,
539 : TM_FailureData *tmfd,
540 : bool changingPart);
541 :
542 : /* see table_tuple_update() for reference about parameters */
543 : TM_Result (*tuple_update) (Relation rel,
544 : ItemPointer otid,
545 : TupleTableSlot *slot,
546 : CommandId cid,
547 : Snapshot snapshot,
548 : Snapshot crosscheck,
549 : bool wait,
550 : TM_FailureData *tmfd,
551 : LockTupleMode *lockmode,
552 : TU_UpdateIndexes *update_indexes);
553 :
554 : /* see table_tuple_lock() for reference about parameters */
555 : TM_Result (*tuple_lock) (Relation rel,
556 : ItemPointer tid,
557 : Snapshot snapshot,
558 : TupleTableSlot *slot,
559 : CommandId cid,
560 : LockTupleMode mode,
561 : LockWaitPolicy wait_policy,
562 : uint8 flags,
563 : TM_FailureData *tmfd);
564 :
565 : /*
566 : * Perform operations necessary to complete insertions made via
567 : * tuple_insert and multi_insert with a BulkInsertState specified. In-tree
568 : * access methods ceased to use this.
569 : *
570 : * Typically callers of tuple_insert and multi_insert will just pass all
571 : * the flags that apply to them, and each AM has to decide which of them
572 : * make sense for it, and then only take actions in finish_bulk_insert for
573 : * those flags, and ignore others.
574 : *
575 : * Optional callback.
576 : */
577 : void (*finish_bulk_insert) (Relation rel, int options);
578 :
579 :
580 : /* ------------------------------------------------------------------------
581 : * DDL related functionality.
582 : * ------------------------------------------------------------------------
583 : */
584 :
585 : /*
586 : * This callback needs to create new relation storage for `rel`, with
587 : * appropriate durability behaviour for `persistence`.
588 : *
589 : * Note that only the subset of the relcache filled by
590 : * RelationBuildLocalRelation() can be relied upon and that the relation's
591 : * catalog entries will either not yet exist (new relation), or will still
592 : * reference the old relfilelocator.
593 : *
594 : * As output *freezeXid, *minmulti must be set to the values appropriate
595 : * for pg_class.{relfrozenxid, relminmxid}. For AMs that don't need those
596 : * fields to be filled they can be set to InvalidTransactionId and
597 : * InvalidMultiXactId, respectively.
598 : *
599 : * See also table_relation_set_new_filelocator().
600 : */
601 : void (*relation_set_new_filelocator) (Relation rel,
602 : const RelFileLocator *newrlocator,
603 : char persistence,
604 : TransactionId *freezeXid,
605 : MultiXactId *minmulti);
606 :
607 : /*
608 : * This callback needs to remove all contents from `rel`'s current
609 : * relfilelocator. No provisions for transactional behaviour need to be
610 : * made. Often this can be implemented by truncating the underlying
611 : * storage to its minimal size.
612 : *
613 : * See also table_relation_nontransactional_truncate().
614 : */
615 : void (*relation_nontransactional_truncate) (Relation rel);
616 :
617 : /*
618 : * See table_relation_copy_data().
619 : *
620 : * This can typically be implemented by directly copying the underlying
621 : * storage, unless it contains references to the tablespace internally.
622 : */
623 : void (*relation_copy_data) (Relation rel,
624 : const RelFileLocator *newrlocator);
625 :
626 : /* See table_relation_copy_for_cluster() */
627 : void (*relation_copy_for_cluster) (Relation OldTable,
628 : Relation NewTable,
629 : Relation OldIndex,
630 : bool use_sort,
631 : TransactionId OldestXmin,
632 : TransactionId *xid_cutoff,
633 : MultiXactId *multi_cutoff,
634 : double *num_tuples,
635 : double *tups_vacuumed,
636 : double *tups_recently_dead);
637 :
638 : /*
639 : * React to VACUUM command on the relation. The VACUUM can be triggered by
640 : * a user or by autovacuum. The specific actions performed by the AM will
641 : * depend heavily on the individual AM.
642 : *
643 : * On entry a transaction is already established, and the relation is
644 : * locked with a ShareUpdateExclusive lock.
645 : *
646 : * Note that neither VACUUM FULL (and CLUSTER), nor ANALYZE go through
647 : * this routine, even if (for ANALYZE) it is part of the same VACUUM
648 : * command.
649 : *
650 : * There probably, in the future, needs to be a separate callback to
651 : * integrate with autovacuum's scheduling.
652 : */
653 : void (*relation_vacuum) (Relation rel,
654 : struct VacuumParams *params,
655 : BufferAccessStrategy bstrategy);
656 :
657 : /*
658 : * Prepare to analyze block `blockno` of `scan`. The scan has been started
659 : * with table_beginscan_analyze(). See also
660 : * table_scan_analyze_next_block().
661 : *
662 : * The callback may acquire resources like locks that are held until
663 : * table_scan_analyze_next_tuple() returns false. It e.g. can make sense
664 : * to hold a lock until all tuples on a block have been analyzed by
665 : * scan_analyze_next_tuple.
666 : *
667 : * The callback can return false if the block is not suitable for
668 : * sampling, e.g. because it's a metapage that could never contain tuples.
669 : *
670 : * XXX: This obviously is primarily suited for block-based AMs. It's not
671 : * clear what a good interface for non block based AMs would be, so there
672 : * isn't one yet.
673 : */
674 : bool (*scan_analyze_next_block) (TableScanDesc scan,
675 : ReadStream *stream);
676 :
677 : /*
678 : * See table_scan_analyze_next_tuple().
679 : *
680 : * Not every AM might have a meaningful concept of dead rows, in which
681 : * case it's OK to not increment *deadrows - but note that that may
682 : * influence autovacuum scheduling (see comment for relation_vacuum
683 : * callback).
684 : */
685 : bool (*scan_analyze_next_tuple) (TableScanDesc scan,
686 : TransactionId OldestXmin,
687 : double *liverows,
688 : double *deadrows,
689 : TupleTableSlot *slot);
690 :
691 : /* see table_index_build_range_scan for reference about parameters */
692 : double (*index_build_range_scan) (Relation table_rel,
693 : Relation index_rel,
694 : struct IndexInfo *index_info,
695 : bool allow_sync,
696 : bool anyvisible,
697 : bool progress,
698 : BlockNumber start_blockno,
699 : BlockNumber numblocks,
700 : IndexBuildCallback callback,
701 : void *callback_state,
702 : TableScanDesc scan);
703 :
704 : /* see table_index_validate_scan for reference about parameters */
705 : void (*index_validate_scan) (Relation table_rel,
706 : Relation index_rel,
707 : struct IndexInfo *index_info,
708 : Snapshot snapshot,
709 : struct ValidateIndexState *state);
710 :
711 :
712 : /* ------------------------------------------------------------------------
713 : * Miscellaneous functions.
714 : * ------------------------------------------------------------------------
715 : */
716 :
717 : /*
718 : * See table_relation_size().
719 : *
720 : * Note that currently a few callers use the MAIN_FORKNUM size to figure
721 : * out the range of potentially interesting blocks (brin, analyze). It's
722 : * probable that we'll need to revise the interface for those at some
723 : * point.
724 : */
725 : uint64 (*relation_size) (Relation rel, ForkNumber forkNumber);
726 :
727 :
728 : /*
729 : * This callback should return true if the relation requires a TOAST table
730 : * and false if it does not. It may wish to examine the relation's tuple
731 : * descriptor before making a decision, but if it uses some other method
732 : * of storing large values (or if it does not support them) it can simply
733 : * return false.
734 : */
735 : bool (*relation_needs_toast_table) (Relation rel);
736 :
737 : /*
738 : * This callback should return the OID of the table AM that implements
739 : * TOAST tables for this AM. If the relation_needs_toast_table callback
740 : * always returns false, this callback is not required.
741 : */
742 : Oid (*relation_toast_am) (Relation rel);
743 :
744 : /*
745 : * This callback is invoked when detoasting a value stored in a toast
746 : * table implemented by this AM. See table_relation_fetch_toast_slice()
747 : * for more details.
748 : */
749 : void (*relation_fetch_toast_slice) (Relation toastrel, Oid valueid,
750 : int32 attrsize,
751 : int32 sliceoffset,
752 : int32 slicelength,
753 : struct varlena *result);
754 :
755 :
756 : /* ------------------------------------------------------------------------
757 : * Planner related functions.
758 : * ------------------------------------------------------------------------
759 : */
760 :
761 : /*
762 : * See table_relation_estimate_size().
763 : *
764 : * While block oriented, it shouldn't be too hard for an AM that doesn't
765 : * internally use blocks to convert into a usable representation.
766 : *
767 : * This differs from the relation_size callback by returning size
768 : * estimates (both relation size and tuple count) for planning purposes,
769 : * rather than returning a currently correct estimate.
770 : */
771 : void (*relation_estimate_size) (Relation rel, int32 *attr_widths,
772 : BlockNumber *pages, double *tuples,
773 : double *allvisfrac);
774 :
775 :
776 : /* ------------------------------------------------------------------------
777 : * Executor related functions.
778 : * ------------------------------------------------------------------------
779 : */
780 :
781 : /*
782 : * Prepare to fetch / check / return tuples from `blockno` as part of a
783 : * bitmap table scan. `scan` was started via table_beginscan_bm(). Return
784 : * false if the bitmap is exhausted and true otherwise.
785 : *
786 : * This will typically read and pin the target block, and do the necessary
787 : * work to allow scan_bitmap_next_tuple() to return tuples (e.g. it might
788 : * make sense to perform tuple visibility checks at this time).
789 : *
790 : * `lossy_pages` and `exact_pages` are EXPLAIN counters that can be
791 : * incremented by the table AM to indicate whether or not the block's
792 : * representation in the bitmap is lossy.
793 : *
794 : * `recheck` is set by the table AM to indicate whether or not the tuples
795 : * from this block should be rechecked. Tuples from lossy pages will
796 : * always need to be rechecked, but some non-lossy pages' tuples may also
797 : * require recheck.
798 : *
799 : * `blockno` is the current block and is set by the table AM. The table AM
800 : * is responsible for advancing the main iterator, but the bitmap table
801 : * scan code still advances the prefetch iterator. `blockno` is used by
802 : * bitmap table scan code to validate that the prefetch block stays ahead
803 : * of the current block.
804 : *
805 : * XXX: Currently this may only be implemented if the AM uses md.c as its
806 : * storage manager, and uses ItemPointer->ip_blkid in a manner that maps
807 : * blockids directly to the underlying storage. nodeBitmapHeapscan.c
808 : * performs prefetching directly using that interface. This probably
809 : * needs to be rectified at a later point.
810 : *
811 : * XXX: Currently this may only be implemented if the AM uses the
812 : * visibilitymap, as nodeBitmapHeapscan.c unconditionally accesses it to
813 : * perform prefetching. This probably needs to be rectified at a later
814 : * point.
815 : *
816 : * Optional callback, but either both scan_bitmap_next_block and
817 : * scan_bitmap_next_tuple need to exist, or neither.
818 : */
819 : bool (*scan_bitmap_next_block) (TableScanDesc scan,
820 : BlockNumber *blockno,
821 : bool *recheck,
822 : uint64 *lossy_pages,
823 : uint64 *exact_pages);
824 :
825 : /*
826 : * Fetch the next tuple of a bitmap table scan into `slot` and return true
827 : * if a visible tuple was found, false otherwise.
828 : *
829 : * Optional callback, but either both scan_bitmap_next_block and
830 : * scan_bitmap_next_tuple need to exist, or neither.
831 : */
832 : bool (*scan_bitmap_next_tuple) (TableScanDesc scan,
833 : TupleTableSlot *slot);
834 :
835 : /*
836 : * Prepare to fetch tuples from the next block in a sample scan. Return
837 : * false if the sample scan is finished, true otherwise. `scan` was
838 : * started via table_beginscan_sampling().
839 : *
840 : * Typically this will first determine the target block by calling the
841 : * TsmRoutine's NextSampleBlock() callback if not NULL, or alternatively
842 : * perform a sequential scan over all blocks. The determined block is
843 : * then typically read and pinned.
844 : *
845 : * As the TsmRoutine interface is block based, a block needs to be passed
846 : * to NextSampleBlock(). If that's not appropriate for an AM, it
847 : * internally needs to perform mapping between the internal and a block
848 : * based representation.
849 : *
850 : * Note that it's not acceptable to hold deadlock prone resources such as
851 : * lwlocks until scan_sample_next_tuple() has exhausted the tuples on the
852 : * block - the tuple is likely to be returned to an upper query node, and
853 : * the next call could be off a long while. Holding buffer pins and such
854 : * is obviously OK.
855 : *
856 : * Currently it is required to implement this interface, as there's no
857 : * alternative way (contrary e.g. to bitmap scans) to implement sample
858 : * scans. If infeasible to implement, the AM may raise an error.
859 : */
860 : bool (*scan_sample_next_block) (TableScanDesc scan,
861 : struct SampleScanState *scanstate);
862 :
863 : /*
864 : * This callback, only called after scan_sample_next_block has returned
865 : * true, should determine the next tuple to be returned from the selected
866 : * block using the TsmRoutine's NextSampleTuple() callback.
867 : *
868 : * The callback needs to perform visibility checks, and only return
869 : * visible tuples. That obviously can mean calling NextSampleTuple()
870 : * multiple times.
871 : *
872 : * The TsmRoutine interface assumes that there's a maximum offset on a
873 : * given page, so if that doesn't apply to an AM, it needs to emulate that
874 : * assumption somehow.
875 : */
876 : bool (*scan_sample_next_tuple) (TableScanDesc scan,
877 : struct SampleScanState *scanstate,
878 : TupleTableSlot *slot);
879 :
880 : } TableAmRoutine;
881 :
882 :
883 : /* ----------------------------------------------------------------------------
884 : * Slot functions.
885 : * ----------------------------------------------------------------------------
886 : */
887 :
888 : /*
889 : * Returns slot callbacks suitable for holding tuples of the appropriate type
890 : * for the relation. Works for tables, views, foreign tables and partitioned
891 : * tables.
892 : */
893 : extern const TupleTableSlotOps *table_slot_callbacks(Relation relation);
894 :
895 : /*
896 : * Returns slot using the callbacks returned by table_slot_callbacks(), and
897 : * registers it on *reglist.
898 : */
899 : extern TupleTableSlot *table_slot_create(Relation relation, List **reglist);
900 :
901 :
902 : /* ----------------------------------------------------------------------------
903 : * Table scan functions.
904 : * ----------------------------------------------------------------------------
905 : */
906 :
907 : /*
908 : * Start a scan of `rel`. Returned tuples pass a visibility test of
909 : * `snapshot`, and if nkeys != 0, the results are filtered by those scan keys.
910 : */
911 : static inline TableScanDesc
912 178680 : table_beginscan(Relation rel, Snapshot snapshot,
913 : int nkeys, struct ScanKeyData *key)
914 : {
915 178680 : uint32 flags = SO_TYPE_SEQSCAN |
916 : SO_ALLOW_STRAT | SO_ALLOW_SYNC | SO_ALLOW_PAGEMODE;
917 :
918 178680 : return rel->rd_tableam->scan_begin(rel, snapshot, nkeys, key, NULL, flags);
919 : }
920 :
921 : /*
922 : * Like table_beginscan(), but for scanning catalog. It'll automatically use a
923 : * snapshot appropriate for scanning catalog relations.
924 : */
925 : extern TableScanDesc table_beginscan_catalog(Relation relation, int nkeys,
926 : struct ScanKeyData *key);
927 :
928 : /*
929 : * Like table_beginscan(), but table_beginscan_strat() offers an extended API
930 : * that lets the caller control whether a nondefault buffer access strategy
931 : * can be used, and whether syncscan can be chosen (possibly resulting in the
932 : * scan not starting from block zero). Both of these default to true with
933 : * plain table_beginscan.
934 : */
935 : static inline TableScanDesc
936 388598 : table_beginscan_strat(Relation rel, Snapshot snapshot,
937 : int nkeys, struct ScanKeyData *key,
938 : bool allow_strat, bool allow_sync)
939 : {
940 388598 : uint32 flags = SO_TYPE_SEQSCAN | SO_ALLOW_PAGEMODE;
941 :
942 388598 : if (allow_strat)
943 388598 : flags |= SO_ALLOW_STRAT;
944 388598 : if (allow_sync)
945 50254 : flags |= SO_ALLOW_SYNC;
946 :
947 388598 : return rel->rd_tableam->scan_begin(rel, snapshot, nkeys, key, NULL, flags);
948 : }
949 :
950 : /*
951 : * table_beginscan_bm is an alternative entry point for setting up a
952 : * TableScanDesc for a bitmap heap scan. Although that scan technology is
953 : * really quite unlike a standard seqscan, there is just enough commonality to
954 : * make it worth using the same data structure.
955 : */
956 : static inline TableScanDesc
957 15432 : table_beginscan_bm(Relation rel, Snapshot snapshot,
958 : int nkeys, struct ScanKeyData *key, bool need_tuple)
959 : {
960 : TableScanDesc result;
961 15432 : uint32 flags = SO_TYPE_BITMAPSCAN | SO_ALLOW_PAGEMODE;
962 :
963 15432 : if (need_tuple)
964 12566 : flags |= SO_NEED_TUPLES;
965 :
966 15432 : result = rel->rd_tableam->scan_begin(rel, snapshot, nkeys, key,
967 : NULL, flags);
968 15432 : result->st.bitmap.rs_shared_iterator = NULL;
969 15432 : result->st.bitmap.rs_iterator = NULL;
970 15432 : return result;
971 : }
972 :
973 : /*
974 : * table_beginscan_sampling is an alternative entry point for setting up a
975 : * TableScanDesc for a TABLESAMPLE scan. As with bitmap scans, it's worth
976 : * using the same data structure although the behavior is rather different.
977 : * In addition to the options offered by table_beginscan_strat, this call
978 : * also allows control of whether page-mode visibility checking is used.
979 : */
980 : static inline TableScanDesc
981 146 : table_beginscan_sampling(Relation rel, Snapshot snapshot,
982 : int nkeys, struct ScanKeyData *key,
983 : bool allow_strat, bool allow_sync,
984 : bool allow_pagemode)
985 : {
986 146 : uint32 flags = SO_TYPE_SAMPLESCAN;
987 :
988 146 : if (allow_strat)
989 134 : flags |= SO_ALLOW_STRAT;
990 146 : if (allow_sync)
991 66 : flags |= SO_ALLOW_SYNC;
992 146 : if (allow_pagemode)
993 122 : flags |= SO_ALLOW_PAGEMODE;
994 :
995 146 : return rel->rd_tableam->scan_begin(rel, snapshot, nkeys, key, NULL, flags);
996 : }
997 :
998 : /*
999 : * table_beginscan_tid is an alternative entry point for setting up a
1000 : * TableScanDesc for a Tid scan. As with bitmap scans, it's worth using
1001 : * the same data structure although the behavior is rather different.
1002 : */
1003 : static inline TableScanDesc
1004 682 : table_beginscan_tid(Relation rel, Snapshot snapshot)
1005 : {
1006 682 : uint32 flags = SO_TYPE_TIDSCAN;
1007 :
1008 682 : return rel->rd_tableam->scan_begin(rel, snapshot, 0, NULL, NULL, flags);
1009 : }
1010 :
1011 : /*
1012 : * table_beginscan_analyze is an alternative entry point for setting up a
1013 : * TableScanDesc for an ANALYZE scan. As with bitmap scans, it's worth using
1014 : * the same data structure although the behavior is rather different.
1015 : */
1016 : static inline TableScanDesc
1017 14514 : table_beginscan_analyze(Relation rel)
1018 : {
1019 14514 : uint32 flags = SO_TYPE_ANALYZE;
1020 :
1021 14514 : return rel->rd_tableam->scan_begin(rel, NULL, 0, NULL, NULL, flags);
1022 : }
1023 :
1024 : /*
1025 : * End relation scan.
1026 : */
1027 : static inline void
1028 659482 : table_endscan(TableScanDesc scan)
1029 : {
1030 659482 : scan->rs_rd->rd_tableam->scan_end(scan);
1031 659482 : }
1032 :
1033 : /*
1034 : * Restart a relation scan.
1035 : */
1036 : static inline void
1037 1011414 : table_rescan(TableScanDesc scan,
1038 : struct ScanKeyData *key)
1039 : {
1040 1011414 : scan->rs_rd->rd_tableam->scan_rescan(scan, key, false, false, false, false);
1041 1011414 : }
1042 :
1043 : /*
1044 : * Restart a relation scan after changing params.
1045 : *
1046 : * This call allows changing the buffer strategy, syncscan, and pagemode
1047 : * options before starting a fresh scan. Note that although the actual use of
1048 : * syncscan might change (effectively, enabling or disabling reporting), the
1049 : * previously selected startblock will be kept.
1050 : */
1051 : static inline void
1052 30 : table_rescan_set_params(TableScanDesc scan, struct ScanKeyData *key,
1053 : bool allow_strat, bool allow_sync, bool allow_pagemode)
1054 : {
1055 30 : scan->rs_rd->rd_tableam->scan_rescan(scan, key, true,
1056 : allow_strat, allow_sync,
1057 : allow_pagemode);
1058 30 : }
1059 :
1060 : /*
1061 : * Return next tuple from `scan`, store in slot.
1062 : */
1063 : static inline bool
1064 78811864 : table_scan_getnextslot(TableScanDesc sscan, ScanDirection direction, TupleTableSlot *slot)
1065 : {
1066 78811864 : slot->tts_tableOid = RelationGetRelid(sscan->rs_rd);
1067 :
1068 : /* We don't expect actual scans using NoMovementScanDirection */
1069 : Assert(direction == ForwardScanDirection ||
1070 : direction == BackwardScanDirection);
1071 :
1072 : /*
1073 : * We don't expect direct calls to table_scan_getnextslot with valid
1074 : * CheckXidAlive for catalog or regular tables. See detailed comments in
1075 : * xact.c where these variables are declared.
1076 : */
1077 78811864 : if (unlikely(TransactionIdIsValid(CheckXidAlive) && !bsysscan))
1078 0 : elog(ERROR, "unexpected table_scan_getnextslot call during logical decoding");
1079 :
1080 78811864 : return sscan->rs_rd->rd_tableam->scan_getnextslot(sscan, direction, slot);
1081 : }
1082 :
1083 : /* ----------------------------------------------------------------------------
1084 : * TID Range scanning related functions.
1085 : * ----------------------------------------------------------------------------
1086 : */
1087 :
1088 : /*
1089 : * table_beginscan_tidrange is the entry point for setting up a TableScanDesc
1090 : * for a TID range scan.
1091 : */
1092 : static inline TableScanDesc
1093 112 : table_beginscan_tidrange(Relation rel, Snapshot snapshot,
1094 : ItemPointer mintid,
1095 : ItemPointer maxtid)
1096 : {
1097 : TableScanDesc sscan;
1098 112 : uint32 flags = SO_TYPE_TIDRANGESCAN | SO_ALLOW_PAGEMODE;
1099 :
1100 112 : sscan = rel->rd_tableam->scan_begin(rel, snapshot, 0, NULL, NULL, flags);
1101 :
1102 : /* Set the range of TIDs to scan */
1103 112 : sscan->rs_rd->rd_tableam->scan_set_tidrange(sscan, mintid, maxtid);
1104 :
1105 112 : return sscan;
1106 : }
1107 :
1108 : /*
1109 : * table_rescan_tidrange resets the scan position and sets the minimum and
1110 : * maximum TID range to scan for a TableScanDesc created by
1111 : * table_beginscan_tidrange.
1112 : */
1113 : static inline void
1114 66 : table_rescan_tidrange(TableScanDesc sscan, ItemPointer mintid,
1115 : ItemPointer maxtid)
1116 : {
1117 : /* Ensure table_beginscan_tidrange() was used. */
1118 : Assert((sscan->rs_flags & SO_TYPE_TIDRANGESCAN) != 0);
1119 :
1120 66 : sscan->rs_rd->rd_tableam->scan_rescan(sscan, NULL, false, false, false, false);
1121 66 : sscan->rs_rd->rd_tableam->scan_set_tidrange(sscan, mintid, maxtid);
1122 66 : }
1123 :
1124 : /*
1125 : * Fetch the next tuple from `sscan` for a TID range scan created by
1126 : * table_beginscan_tidrange(). Stores the tuple in `slot` and returns true,
1127 : * or returns false if no more tuples exist in the range.
1128 : */
1129 : static inline bool
1130 5940 : table_scan_getnextslot_tidrange(TableScanDesc sscan, ScanDirection direction,
1131 : TupleTableSlot *slot)
1132 : {
1133 : /* Ensure table_beginscan_tidrange() was used. */
1134 : Assert((sscan->rs_flags & SO_TYPE_TIDRANGESCAN) != 0);
1135 :
1136 : /* We don't expect actual scans using NoMovementScanDirection */
1137 : Assert(direction == ForwardScanDirection ||
1138 : direction == BackwardScanDirection);
1139 :
1140 5940 : return sscan->rs_rd->rd_tableam->scan_getnextslot_tidrange(sscan,
1141 : direction,
1142 : slot);
1143 : }
1144 :
1145 :
1146 : /* ----------------------------------------------------------------------------
1147 : * Parallel table scan related functions.
1148 : * ----------------------------------------------------------------------------
1149 : */
1150 :
1151 : /*
1152 : * Estimate the size of shared memory needed for a parallel scan of this
1153 : * relation.
1154 : */
1155 : extern Size table_parallelscan_estimate(Relation rel, Snapshot snapshot);
1156 :
1157 : /*
1158 : * Initialize ParallelTableScanDesc for a parallel scan of this
1159 : * relation. `pscan` needs to be sized according to parallelscan_estimate()
1160 : * for the same relation. Call this just once in the leader process; then,
1161 : * individual workers attach via table_beginscan_parallel.
1162 : */
1163 : extern void table_parallelscan_initialize(Relation rel,
1164 : ParallelTableScanDesc pscan,
1165 : Snapshot snapshot);
1166 :
1167 : /*
1168 : * Begin a parallel scan. `pscan` needs to have been initialized with
1169 : * table_parallelscan_initialize(), for the same relation. The initialization
1170 : * does not need to have happened in this backend.
1171 : *
1172 : * Caller must hold a suitable lock on the relation.
1173 : */
1174 : extern TableScanDesc table_beginscan_parallel(Relation relation,
1175 : ParallelTableScanDesc pscan);
1176 :
1177 : /*
1178 : * Restart a parallel scan. Call this in the leader process. Caller is
1179 : * responsible for making sure that all workers have finished the scan
1180 : * beforehand.
1181 : */
1182 : static inline void
1183 228 : table_parallelscan_reinitialize(Relation rel, ParallelTableScanDesc pscan)
1184 : {
1185 228 : rel->rd_tableam->parallelscan_reinitialize(rel, pscan);
1186 228 : }
1187 :
1188 :
1189 : /* ----------------------------------------------------------------------------
1190 : * Index scan related functions.
1191 : * ----------------------------------------------------------------------------
1192 : */
1193 :
1194 : /*
1195 : * Prepare to fetch tuples from the relation, as needed when fetching tuples
1196 : * for an index scan.
1197 : *
1198 : * Tuples for an index scan can then be fetched via table_index_fetch_tuple().
1199 : */
1200 : static inline IndexFetchTableData *
1201 24050612 : table_index_fetch_begin(Relation rel)
1202 : {
1203 24050612 : return rel->rd_tableam->index_fetch_begin(rel);
1204 : }
1205 :
1206 : /*
1207 : * Reset index fetch. Typically this will release cross index fetch resources
1208 : * held in IndexFetchTableData.
1209 : */
1210 : static inline void
1211 19109452 : table_index_fetch_reset(struct IndexFetchTableData *scan)
1212 : {
1213 19109452 : scan->rel->rd_tableam->index_fetch_reset(scan);
1214 19109452 : }
1215 :
1216 : /*
1217 : * Release resources and deallocate index fetch.
1218 : */
1219 : static inline void
1220 24049004 : table_index_fetch_end(struct IndexFetchTableData *scan)
1221 : {
1222 24049004 : scan->rel->rd_tableam->index_fetch_end(scan);
1223 24049004 : }
1224 :
1225 : /*
1226 : * Fetches, as part of an index scan, tuple at `tid` into `slot`, after doing
1227 : * a visibility test according to `snapshot`. If a tuple was found and passed
1228 : * the visibility test, returns true, false otherwise. Note that *tid may be
1229 : * modified when we return true (see later remarks on multiple row versions
1230 : * reachable via a single index entry).
1231 : *
1232 : * *call_again needs to be false on the first call to table_index_fetch_tuple() for
1233 : * a tid. If there potentially is another tuple matching the tid, *call_again
1234 : * will be set to true, signaling that table_index_fetch_tuple() should be called
1235 : * again for the same tid.
1236 : *
1237 : * *all_dead, if all_dead is not NULL, will be set to true by
1238 : * table_index_fetch_tuple() iff it is guaranteed that no backend needs to see
1239 : * that tuple. Index AMs can use that to avoid returning that tid in future
1240 : * searches.
1241 : *
1242 : * The difference between this function and table_tuple_fetch_row_version()
1243 : * is that this function returns the currently visible version of a row if
1244 : * the AM supports storing multiple row versions reachable via a single index
1245 : * entry (like heap's HOT). Whereas table_tuple_fetch_row_version() only
1246 : * evaluates the tuple exactly at `tid`. Outside of index entry ->table tuple
1247 : * lookups, table_tuple_fetch_row_version() is what's usually needed.
1248 : */
1249 : static inline bool
1250 33906078 : table_index_fetch_tuple(struct IndexFetchTableData *scan,
1251 : ItemPointer tid,
1252 : Snapshot snapshot,
1253 : TupleTableSlot *slot,
1254 : bool *call_again, bool *all_dead)
1255 : {
1256 : /*
1257 : * We don't expect direct calls to table_index_fetch_tuple with valid
1258 : * CheckXidAlive for catalog or regular tables. See detailed comments in
1259 : * xact.c where these variables are declared.
1260 : */
1261 33906078 : if (unlikely(TransactionIdIsValid(CheckXidAlive) && !bsysscan))
1262 0 : elog(ERROR, "unexpected table_index_fetch_tuple call during logical decoding");
1263 :
1264 33906078 : return scan->rel->rd_tableam->index_fetch_tuple(scan, tid, snapshot,
1265 : slot, call_again,
1266 : all_dead);
1267 : }
1268 :
1269 : /*
1270 : * This is a convenience wrapper around table_index_fetch_tuple() which
1271 : * returns whether there are table tuple items corresponding to an index
1272 : * entry. This likely is only useful to verify if there's a conflict in a
1273 : * unique index.
1274 : */
1275 : extern bool table_index_fetch_tuple_check(Relation rel,
1276 : ItemPointer tid,
1277 : Snapshot snapshot,
1278 : bool *all_dead);
1279 :
1280 :
1281 : /* ------------------------------------------------------------------------
1282 : * Functions for non-modifying operations on individual tuples
1283 : * ------------------------------------------------------------------------
1284 : */
1285 :
1286 :
1287 : /*
1288 : * Fetch tuple at `tid` into `slot`, after doing a visibility test according to
1289 : * `snapshot`. If a tuple was found and passed the visibility test, returns
1290 : * true, false otherwise.
1291 : *
1292 : * See table_index_fetch_tuple's comment about what the difference between
1293 : * these functions is. It is correct to use this function outside of index
1294 : * entry->table tuple lookups.
1295 : */
1296 : static inline bool
1297 345024 : table_tuple_fetch_row_version(Relation rel,
1298 : ItemPointer tid,
1299 : Snapshot snapshot,
1300 : TupleTableSlot *slot)
1301 : {
1302 : /*
1303 : * We don't expect direct calls to table_tuple_fetch_row_version with
1304 : * valid CheckXidAlive for catalog or regular tables. See detailed
1305 : * comments in xact.c where these variables are declared.
1306 : */
1307 345024 : if (unlikely(TransactionIdIsValid(CheckXidAlive) && !bsysscan))
1308 0 : elog(ERROR, "unexpected table_tuple_fetch_row_version call during logical decoding");
1309 :
1310 345024 : return rel->rd_tableam->tuple_fetch_row_version(rel, tid, snapshot, slot);
1311 : }
1312 :
1313 : /*
1314 : * Verify that `tid` is a potentially valid tuple identifier. That doesn't
1315 : * mean that the pointed to row needs to exist or be visible, but that
1316 : * attempting to fetch the row (e.g. with table_tuple_get_latest_tid() or
1317 : * table_tuple_fetch_row_version()) should not error out if called with that
1318 : * tid.
1319 : *
1320 : * `scan` needs to have been started via table_beginscan().
1321 : */
1322 : static inline bool
1323 346 : table_tuple_tid_valid(TableScanDesc scan, ItemPointer tid)
1324 : {
1325 346 : return scan->rs_rd->rd_tableam->tuple_tid_valid(scan, tid);
1326 : }
1327 :
1328 : /*
1329 : * Return the latest version of the tuple at `tid`, by updating `tid` to
1330 : * point at the newest version.
1331 : */
1332 : extern void table_tuple_get_latest_tid(TableScanDesc scan, ItemPointer tid);
1333 :
1334 : /*
1335 : * Return true iff tuple in slot satisfies the snapshot.
1336 : *
1337 : * This assumes the slot's tuple is valid, and of the appropriate type for the
1338 : * AM.
1339 : *
1340 : * Some AMs might modify the data underlying the tuple as a side-effect. If so
1341 : * they ought to mark the relevant buffer dirty.
1342 : */
1343 : static inline bool
1344 219648 : table_tuple_satisfies_snapshot(Relation rel, TupleTableSlot *slot,
1345 : Snapshot snapshot)
1346 : {
1347 219648 : return rel->rd_tableam->tuple_satisfies_snapshot(rel, slot, snapshot);
1348 : }
1349 :
1350 : /*
1351 : * Determine which index tuples are safe to delete based on their table TID.
1352 : *
1353 : * Determines which entries from index AM caller's TM_IndexDeleteOp state
1354 : * point to vacuumable table tuples. Entries that are found by tableam to be
1355 : * vacuumable are naturally safe for index AM to delete, and so get directly
1356 : * marked as deletable. See comments above TM_IndexDelete and comments above
1357 : * TM_IndexDeleteOp for full details.
1358 : *
1359 : * Returns a snapshotConflictHorizon transaction ID that caller places in
1360 : * its index deletion WAL record. This might be used during subsequent REDO
1361 : * of the WAL record when in Hot Standby mode -- a recovery conflict for the
1362 : * index deletion operation might be required on the standby.
1363 : */
1364 : static inline TransactionId
1365 10604 : table_index_delete_tuples(Relation rel, TM_IndexDeleteOp *delstate)
1366 : {
1367 10604 : return rel->rd_tableam->index_delete_tuples(rel, delstate);
1368 : }
1369 :
1370 :
1371 : /* ----------------------------------------------------------------------------
1372 : * Functions for manipulations of physical tuples.
1373 : * ----------------------------------------------------------------------------
1374 : */
1375 :
1376 : /*
1377 : * Insert a tuple from a slot into table AM routine.
1378 : *
1379 : * The options bitmask allows the caller to specify options that may change the
1380 : * behaviour of the AM. The AM will ignore options that it does not support.
1381 : *
1382 : * If the TABLE_INSERT_SKIP_FSM option is specified, AMs are free to not reuse
1383 : * free space in the relation. This can save some cycles when we know the
1384 : * relation is new and doesn't contain useful amounts of free space.
1385 : * TABLE_INSERT_SKIP_FSM is commonly passed directly to
1386 : * RelationGetBufferForTuple. See that method for more information.
1387 : *
1388 : * TABLE_INSERT_FROZEN should only be specified for inserts into
1389 : * relation storage created during the current subtransaction and when
1390 : * there are no prior snapshots or pre-existing portals open.
1391 : * This causes rows to be frozen, which is an MVCC violation and
1392 : * requires explicit options chosen by user.
1393 : *
1394 : * TABLE_INSERT_NO_LOGICAL force-disables the emitting of logical decoding
1395 : * information for the tuple. This should solely be used during table rewrites
1396 : * where RelationIsLogicallyLogged(relation) is not yet accurate for the new
1397 : * relation.
1398 : *
1399 : * Note that most of these options will be applied when inserting into the
1400 : * heap's TOAST table, too, if the tuple requires any out-of-line data.
1401 : *
1402 : * The BulkInsertState object (if any; bistate can be NULL for default
1403 : * behavior) is also just passed through to RelationGetBufferForTuple. If
1404 : * `bistate` is provided, table_finish_bulk_insert() needs to be called.
1405 : *
1406 : * On return the slot's tts_tid and tts_tableOid are updated to reflect the
1407 : * insertion. But note that any toasting of fields within the slot is NOT
1408 : * reflected in the slots contents.
1409 : */
1410 : static inline void
1411 13838660 : table_tuple_insert(Relation rel, TupleTableSlot *slot, CommandId cid,
1412 : int options, struct BulkInsertStateData *bistate)
1413 : {
1414 13838660 : rel->rd_tableam->tuple_insert(rel, slot, cid, options,
1415 : bistate);
1416 13838620 : }
1417 :
1418 : /*
1419 : * Perform a "speculative insertion". These can be backed out afterwards
1420 : * without aborting the whole transaction. Other sessions can wait for the
1421 : * speculative insertion to be confirmed, turning it into a regular tuple, or
1422 : * aborted, as if it never existed. Speculatively inserted tuples behave as
1423 : * "value locks" of short duration, used to implement INSERT .. ON CONFLICT.
1424 : *
1425 : * A transaction having performed a speculative insertion has to either abort,
1426 : * or finish the speculative insertion with
1427 : * table_tuple_complete_speculative(succeeded = ...).
1428 : */
1429 : static inline void
1430 4122 : table_tuple_insert_speculative(Relation rel, TupleTableSlot *slot,
1431 : CommandId cid, int options,
1432 : struct BulkInsertStateData *bistate,
1433 : uint32 specToken)
1434 : {
1435 4122 : rel->rd_tableam->tuple_insert_speculative(rel, slot, cid, options,
1436 : bistate, specToken);
1437 4122 : }
1438 :
1439 : /*
1440 : * Complete "speculative insertion" started in the same transaction. If
1441 : * succeeded is true, the tuple is fully inserted, if false, it's removed.
1442 : */
1443 : static inline void
1444 4116 : table_tuple_complete_speculative(Relation rel, TupleTableSlot *slot,
1445 : uint32 specToken, bool succeeded)
1446 : {
1447 4116 : rel->rd_tableam->tuple_complete_speculative(rel, slot, specToken,
1448 : succeeded);
1449 4116 : }
1450 :
1451 : /*
1452 : * Insert multiple tuples into a table.
1453 : *
1454 : * This is like table_tuple_insert(), but inserts multiple tuples in one
1455 : * operation. That's often faster than calling table_tuple_insert() in a loop,
1456 : * because e.g. the AM can reduce WAL logging and page locking overhead.
1457 : *
1458 : * Except for taking `nslots` tuples as input, and an array of TupleTableSlots
1459 : * in `slots`, the parameters for table_multi_insert() are the same as for
1460 : * table_tuple_insert().
1461 : *
1462 : * Note: this leaks memory into the current memory context. You can create a
1463 : * temporary context before calling this, if that's a problem.
1464 : */
1465 : static inline void
1466 2354 : table_multi_insert(Relation rel, TupleTableSlot **slots, int nslots,
1467 : CommandId cid, int options, struct BulkInsertStateData *bistate)
1468 : {
1469 2354 : rel->rd_tableam->multi_insert(rel, slots, nslots,
1470 : cid, options, bistate);
1471 2354 : }
1472 :
1473 : /*
1474 : * Delete a tuple.
1475 : *
1476 : * NB: do not call this directly unless prepared to deal with
1477 : * concurrent-update conditions. Use simple_table_tuple_delete instead.
1478 : *
1479 : * Input parameters:
1480 : * relation - table to be modified (caller must hold suitable lock)
1481 : * tid - TID of tuple to be deleted
1482 : * cid - delete command ID (used for visibility test, and stored into
1483 : * cmax if successful)
1484 : * crosscheck - if not InvalidSnapshot, also check tuple against this
1485 : * wait - true if should wait for any conflicting update to commit/abort
1486 : * Output parameters:
1487 : * tmfd - filled in failure cases (see below)
1488 : * changingPart - true iff the tuple is being moved to another partition
1489 : * table due to an update of the partition key. Otherwise, false.
1490 : *
1491 : * Normal, successful return value is TM_Ok, which means we did actually
1492 : * delete it. Failure return codes are TM_SelfModified, TM_Updated, and
1493 : * TM_BeingModified (the last only possible if wait == false).
1494 : *
1495 : * In the failure cases, the routine fills *tmfd with the tuple's t_ctid,
1496 : * t_xmax, and, if possible, t_cmax. See comments for struct
1497 : * TM_FailureData for additional info.
1498 : */
1499 : static inline TM_Result
1500 1720270 : table_tuple_delete(Relation rel, ItemPointer tid, CommandId cid,
1501 : Snapshot snapshot, Snapshot crosscheck, bool wait,
1502 : TM_FailureData *tmfd, bool changingPart)
1503 : {
1504 1720270 : return rel->rd_tableam->tuple_delete(rel, tid, cid,
1505 : snapshot, crosscheck,
1506 : wait, tmfd, changingPart);
1507 : }
1508 :
1509 : /*
1510 : * Update a tuple.
1511 : *
1512 : * NB: do not call this directly unless you are prepared to deal with
1513 : * concurrent-update conditions. Use simple_table_tuple_update instead.
1514 : *
1515 : * Input parameters:
1516 : * relation - table to be modified (caller must hold suitable lock)
1517 : * otid - TID of old tuple to be replaced
1518 : * slot - newly constructed tuple data to store
1519 : * cid - update command ID (used for visibility test, and stored into
1520 : * cmax/cmin if successful)
1521 : * crosscheck - if not InvalidSnapshot, also check old tuple against this
1522 : * wait - true if should wait for any conflicting update to commit/abort
1523 : * Output parameters:
1524 : * tmfd - filled in failure cases (see below)
1525 : * lockmode - filled with lock mode acquired on tuple
1526 : * update_indexes - in success cases this is set to true if new index entries
1527 : * are required for this tuple
1528 : *
1529 : * Normal, successful return value is TM_Ok, which means we did actually
1530 : * update it. Failure return codes are TM_SelfModified, TM_Updated, and
1531 : * TM_BeingModified (the last only possible if wait == false).
1532 : *
1533 : * On success, the slot's tts_tid and tts_tableOid are updated to match the new
1534 : * stored tuple; in particular, slot->tts_tid is set to the TID where the
1535 : * new tuple was inserted, and its HEAP_ONLY_TUPLE flag is set iff a HOT
1536 : * update was done. However, any TOAST changes in the new tuple's
1537 : * data are not reflected into *newtup.
1538 : *
1539 : * In the failure cases, the routine fills *tmfd with the tuple's t_ctid,
1540 : * t_xmax, and, if possible, t_cmax. See comments for struct TM_FailureData
1541 : * for additional info.
1542 : */
1543 : static inline TM_Result
1544 378346 : table_tuple_update(Relation rel, ItemPointer otid, TupleTableSlot *slot,
1545 : CommandId cid, Snapshot snapshot, Snapshot crosscheck,
1546 : bool wait, TM_FailureData *tmfd, LockTupleMode *lockmode,
1547 : TU_UpdateIndexes *update_indexes)
1548 : {
1549 378346 : return rel->rd_tableam->tuple_update(rel, otid, slot,
1550 : cid, snapshot, crosscheck,
1551 : wait, tmfd,
1552 : lockmode, update_indexes);
1553 : }
1554 :
1555 : /*
1556 : * Lock a tuple in the specified mode.
1557 : *
1558 : * Input parameters:
1559 : * relation: relation containing tuple (caller must hold suitable lock)
1560 : * tid: TID of tuple to lock
1561 : * snapshot: snapshot to use for visibility determinations
1562 : * cid: current command ID (used for visibility test, and stored into
1563 : * tuple's cmax if lock is successful)
1564 : * mode: lock mode desired
1565 : * wait_policy: what to do if tuple lock is not available
1566 : * flags:
1567 : * If TUPLE_LOCK_FLAG_LOCK_UPDATE_IN_PROGRESS, follow the update chain to
1568 : * also lock descendant tuples if lock modes don't conflict.
1569 : * If TUPLE_LOCK_FLAG_FIND_LAST_VERSION, follow the update chain and lock
1570 : * latest version.
1571 : *
1572 : * Output parameters:
1573 : * *slot: contains the target tuple
1574 : * *tmfd: filled in failure cases (see below)
1575 : *
1576 : * Function result may be:
1577 : * TM_Ok: lock was successfully acquired
1578 : * TM_Invisible: lock failed because tuple was never visible to us
1579 : * TM_SelfModified: lock failed because tuple updated by self
1580 : * TM_Updated: lock failed because tuple updated by other xact
1581 : * TM_Deleted: lock failed because tuple deleted by other xact
1582 : * TM_WouldBlock: lock couldn't be acquired and wait_policy is skip
1583 : *
1584 : * In the failure cases other than TM_Invisible and TM_Deleted, the routine
1585 : * fills *tmfd with the tuple's t_ctid, t_xmax, and, if possible, t_cmax. See
1586 : * comments for struct TM_FailureData for additional info.
1587 : */
1588 : static inline TM_Result
1589 169726 : table_tuple_lock(Relation rel, ItemPointer tid, Snapshot snapshot,
1590 : TupleTableSlot *slot, CommandId cid, LockTupleMode mode,
1591 : LockWaitPolicy wait_policy, uint8 flags,
1592 : TM_FailureData *tmfd)
1593 : {
1594 169726 : return rel->rd_tableam->tuple_lock(rel, tid, snapshot, slot,
1595 : cid, mode, wait_policy,
1596 : flags, tmfd);
1597 : }
1598 :
1599 : /*
1600 : * Perform operations necessary to complete insertions made via
1601 : * tuple_insert and multi_insert with a BulkInsertState specified.
1602 : */
1603 : static inline void
1604 3800 : table_finish_bulk_insert(Relation rel, int options)
1605 : {
1606 : /* optional callback */
1607 3800 : if (rel->rd_tableam && rel->rd_tableam->finish_bulk_insert)
1608 0 : rel->rd_tableam->finish_bulk_insert(rel, options);
1609 3800 : }
1610 :
1611 :
1612 : /* ------------------------------------------------------------------------
1613 : * DDL related functionality.
1614 : * ------------------------------------------------------------------------
1615 : */
1616 :
1617 : /*
1618 : * Create storage for `rel` in `newrlocator`, with persistence set to
1619 : * `persistence`.
1620 : *
1621 : * This is used both during relation creation and various DDL operations to
1622 : * create new rel storage that can be filled from scratch. When creating
1623 : * new storage for an existing relfilelocator, this should be called before the
1624 : * relcache entry has been updated.
1625 : *
1626 : * *freezeXid, *minmulti are set to the xid / multixact horizon for the table
1627 : * that pg_class.{relfrozenxid, relminmxid} have to be set to.
1628 : */
1629 : static inline void
1630 60390 : table_relation_set_new_filelocator(Relation rel,
1631 : const RelFileLocator *newrlocator,
1632 : char persistence,
1633 : TransactionId *freezeXid,
1634 : MultiXactId *minmulti)
1635 : {
1636 60390 : rel->rd_tableam->relation_set_new_filelocator(rel, newrlocator,
1637 : persistence, freezeXid,
1638 : minmulti);
1639 60390 : }
1640 :
1641 : /*
1642 : * Remove all table contents from `rel`, in a non-transactional manner.
1643 : * Non-transactional meaning that there's no need to support rollbacks. This
1644 : * commonly only is used to perform truncations for relation storage created in
1645 : * the current transaction.
1646 : */
1647 : static inline void
1648 576 : table_relation_nontransactional_truncate(Relation rel)
1649 : {
1650 576 : rel->rd_tableam->relation_nontransactional_truncate(rel);
1651 576 : }
1652 :
1653 : /*
1654 : * Copy data from `rel` into the new relfilelocator `newrlocator`. The new
1655 : * relfilelocator may not have storage associated before this function is
1656 : * called. This is only supposed to be used for low level operations like
1657 : * changing a relation's tablespace.
1658 : */
1659 : static inline void
1660 98 : table_relation_copy_data(Relation rel, const RelFileLocator *newrlocator)
1661 : {
1662 98 : rel->rd_tableam->relation_copy_data(rel, newrlocator);
1663 98 : }
1664 :
1665 : /*
1666 : * Copy data from `OldTable` into `NewTable`, as part of a CLUSTER or VACUUM
1667 : * FULL.
1668 : *
1669 : * Additional Input parameters:
1670 : * - use_sort - if true, the table contents are sorted appropriate for
1671 : * `OldIndex`; if false and OldIndex is not InvalidOid, the data is copied
1672 : * in that index's order; if false and OldIndex is InvalidOid, no sorting is
1673 : * performed
1674 : * - OldIndex - see use_sort
1675 : * - OldestXmin - computed by vacuum_get_cutoffs(), even when
1676 : * not needed for the relation's AM
1677 : * - *xid_cutoff - ditto
1678 : * - *multi_cutoff - ditto
1679 : *
1680 : * Output parameters:
1681 : * - *xid_cutoff - rel's new relfrozenxid value, may be invalid
1682 : * - *multi_cutoff - rel's new relminmxid value, may be invalid
1683 : * - *tups_vacuumed - stats, for logging, if appropriate for AM
1684 : * - *tups_recently_dead - stats, for logging, if appropriate for AM
1685 : */
1686 : static inline void
1687 546 : table_relation_copy_for_cluster(Relation OldTable, Relation NewTable,
1688 : Relation OldIndex,
1689 : bool use_sort,
1690 : TransactionId OldestXmin,
1691 : TransactionId *xid_cutoff,
1692 : MultiXactId *multi_cutoff,
1693 : double *num_tuples,
1694 : double *tups_vacuumed,
1695 : double *tups_recently_dead)
1696 : {
1697 546 : OldTable->rd_tableam->relation_copy_for_cluster(OldTable, NewTable, OldIndex,
1698 : use_sort, OldestXmin,
1699 : xid_cutoff, multi_cutoff,
1700 : num_tuples, tups_vacuumed,
1701 : tups_recently_dead);
1702 546 : }
1703 :
1704 : /*
1705 : * Perform VACUUM on the relation. The VACUUM can be triggered by a user or by
1706 : * autovacuum. The specific actions performed by the AM will depend heavily on
1707 : * the individual AM.
1708 : *
1709 : * On entry a transaction needs to already been established, and the
1710 : * table is locked with a ShareUpdateExclusive lock.
1711 : *
1712 : * Note that neither VACUUM FULL (and CLUSTER), nor ANALYZE go through this
1713 : * routine, even if (for ANALYZE) it is part of the same VACUUM command.
1714 : */
1715 : static inline void
1716 97130 : table_relation_vacuum(Relation rel, struct VacuumParams *params,
1717 : BufferAccessStrategy bstrategy)
1718 : {
1719 97130 : rel->rd_tableam->relation_vacuum(rel, params, bstrategy);
1720 97130 : }
1721 :
1722 : /*
1723 : * Prepare to analyze the next block in the read stream. The scan needs to
1724 : * have been started with table_beginscan_analyze(). Note that this routine
1725 : * might acquire resources like locks that are held until
1726 : * table_scan_analyze_next_tuple() returns false.
1727 : *
1728 : * Returns false if block is unsuitable for sampling, true otherwise.
1729 : */
1730 : static inline bool
1731 127058 : table_scan_analyze_next_block(TableScanDesc scan, ReadStream *stream)
1732 : {
1733 127058 : return scan->rs_rd->rd_tableam->scan_analyze_next_block(scan, stream);
1734 : }
1735 :
1736 : /*
1737 : * Iterate over tuples in the block selected with
1738 : * table_scan_analyze_next_block() (which needs to have returned true, and
1739 : * this routine may not have returned false for the same block before). If a
1740 : * tuple that's suitable for sampling is found, true is returned and a tuple
1741 : * is stored in `slot`.
1742 : *
1743 : * *liverows and *deadrows are incremented according to the encountered
1744 : * tuples.
1745 : */
1746 : static inline bool
1747 9012872 : table_scan_analyze_next_tuple(TableScanDesc scan, TransactionId OldestXmin,
1748 : double *liverows, double *deadrows,
1749 : TupleTableSlot *slot)
1750 : {
1751 9012872 : return scan->rs_rd->rd_tableam->scan_analyze_next_tuple(scan, OldestXmin,
1752 : liverows, deadrows,
1753 : slot);
1754 : }
1755 :
1756 : /*
1757 : * table_index_build_scan - scan the table to find tuples to be indexed
1758 : *
1759 : * This is called back from an access-method-specific index build procedure
1760 : * after the AM has done whatever setup it needs. The parent table relation
1761 : * is scanned to find tuples that should be entered into the index. Each
1762 : * such tuple is passed to the AM's callback routine, which does the right
1763 : * things to add it to the new index. After we return, the AM's index
1764 : * build procedure does whatever cleanup it needs.
1765 : *
1766 : * The total count of live tuples is returned. This is for updating pg_class
1767 : * statistics. (It's annoying not to be able to do that here, but we want to
1768 : * merge that update with others; see index_update_stats.) Note that the
1769 : * index AM itself must keep track of the number of index tuples; we don't do
1770 : * so here because the AM might reject some of the tuples for its own reasons,
1771 : * such as being unable to store NULLs.
1772 : *
1773 : * If 'progress', the PROGRESS_SCAN_BLOCKS_TOTAL counter is updated when
1774 : * starting the scan, and PROGRESS_SCAN_BLOCKS_DONE is updated as we go along.
1775 : *
1776 : * A side effect is to set indexInfo->ii_BrokenHotChain to true if we detect
1777 : * any potentially broken HOT chains. Currently, we set this if there are any
1778 : * RECENTLY_DEAD or DELETE_IN_PROGRESS entries in a HOT chain, without trying
1779 : * very hard to detect whether they're really incompatible with the chain tip.
1780 : * This only really makes sense for heap AM, it might need to be generalized
1781 : * for other AMs later.
1782 : */
1783 : static inline double
1784 50514 : table_index_build_scan(Relation table_rel,
1785 : Relation index_rel,
1786 : struct IndexInfo *index_info,
1787 : bool allow_sync,
1788 : bool progress,
1789 : IndexBuildCallback callback,
1790 : void *callback_state,
1791 : TableScanDesc scan)
1792 : {
1793 50514 : return table_rel->rd_tableam->index_build_range_scan(table_rel,
1794 : index_rel,
1795 : index_info,
1796 : allow_sync,
1797 : false,
1798 : progress,
1799 : 0,
1800 : InvalidBlockNumber,
1801 : callback,
1802 : callback_state,
1803 : scan);
1804 : }
1805 :
1806 : /*
1807 : * As table_index_build_scan(), except that instead of scanning the complete
1808 : * table, only the given number of blocks are scanned. Scan to end-of-rel can
1809 : * be signaled by passing InvalidBlockNumber as numblocks. Note that
1810 : * restricting the range to scan cannot be done when requesting syncscan.
1811 : *
1812 : * When "anyvisible" mode is requested, all tuples visible to any transaction
1813 : * are indexed and counted as live, including those inserted or deleted by
1814 : * transactions that are still in progress.
1815 : */
1816 : static inline double
1817 2934 : table_index_build_range_scan(Relation table_rel,
1818 : Relation index_rel,
1819 : struct IndexInfo *index_info,
1820 : bool allow_sync,
1821 : bool anyvisible,
1822 : bool progress,
1823 : BlockNumber start_blockno,
1824 : BlockNumber numblocks,
1825 : IndexBuildCallback callback,
1826 : void *callback_state,
1827 : TableScanDesc scan)
1828 : {
1829 2934 : return table_rel->rd_tableam->index_build_range_scan(table_rel,
1830 : index_rel,
1831 : index_info,
1832 : allow_sync,
1833 : anyvisible,
1834 : progress,
1835 : start_blockno,
1836 : numblocks,
1837 : callback,
1838 : callback_state,
1839 : scan);
1840 : }
1841 :
1842 : /*
1843 : * table_index_validate_scan - second table scan for concurrent index build
1844 : *
1845 : * See validate_index() for an explanation.
1846 : */
1847 : static inline void
1848 606 : table_index_validate_scan(Relation table_rel,
1849 : Relation index_rel,
1850 : struct IndexInfo *index_info,
1851 : Snapshot snapshot,
1852 : struct ValidateIndexState *state)
1853 : {
1854 606 : table_rel->rd_tableam->index_validate_scan(table_rel,
1855 : index_rel,
1856 : index_info,
1857 : snapshot,
1858 : state);
1859 606 : }
1860 :
1861 :
1862 : /* ----------------------------------------------------------------------------
1863 : * Miscellaneous functionality
1864 : * ----------------------------------------------------------------------------
1865 : */
1866 :
1867 : /*
1868 : * Return the current size of `rel` in bytes. If `forkNumber` is
1869 : * InvalidForkNumber, return the relation's overall size, otherwise the size
1870 : * for the indicated fork.
1871 : *
1872 : * Note that the overall size might not be the equivalent of the sum of sizes
1873 : * for the individual forks for some AMs, e.g. because the AMs storage does
1874 : * not neatly map onto the builtin types of forks.
1875 : */
1876 : static inline uint64
1877 2314800 : table_relation_size(Relation rel, ForkNumber forkNumber)
1878 : {
1879 2314800 : return rel->rd_tableam->relation_size(rel, forkNumber);
1880 : }
1881 :
1882 : /*
1883 : * table_relation_needs_toast_table - does this relation need a toast table?
1884 : */
1885 : static inline bool
1886 40870 : table_relation_needs_toast_table(Relation rel)
1887 : {
1888 40870 : return rel->rd_tableam->relation_needs_toast_table(rel);
1889 : }
1890 :
1891 : /*
1892 : * Return the OID of the AM that should be used to implement the TOAST table
1893 : * for this relation.
1894 : */
1895 : static inline Oid
1896 16602 : table_relation_toast_am(Relation rel)
1897 : {
1898 16602 : return rel->rd_tableam->relation_toast_am(rel);
1899 : }
1900 :
1901 : /*
1902 : * Fetch all or part of a TOAST value from a TOAST table.
1903 : *
1904 : * If this AM is never used to implement a TOAST table, then this callback
1905 : * is not needed. But, if toasted values are ever stored in a table of this
1906 : * type, then you will need this callback.
1907 : *
1908 : * toastrel is the relation in which the toasted value is stored.
1909 : *
1910 : * valueid identifies which toast value is to be fetched. For the heap,
1911 : * this corresponds to the values stored in the chunk_id column.
1912 : *
1913 : * attrsize is the total size of the toast value to be fetched.
1914 : *
1915 : * sliceoffset is the offset within the toast value of the first byte that
1916 : * should be fetched.
1917 : *
1918 : * slicelength is the number of bytes from the toast value that should be
1919 : * fetched.
1920 : *
1921 : * result is caller-allocated space into which the fetched bytes should be
1922 : * stored.
1923 : */
1924 : static inline void
1925 19930 : table_relation_fetch_toast_slice(Relation toastrel, Oid valueid,
1926 : int32 attrsize, int32 sliceoffset,
1927 : int32 slicelength, struct varlena *result)
1928 : {
1929 19930 : toastrel->rd_tableam->relation_fetch_toast_slice(toastrel, valueid,
1930 : attrsize,
1931 : sliceoffset, slicelength,
1932 : result);
1933 19930 : }
1934 :
1935 :
1936 : /* ----------------------------------------------------------------------------
1937 : * Planner related functionality
1938 : * ----------------------------------------------------------------------------
1939 : */
1940 :
1941 : /*
1942 : * Estimate the current size of the relation, as an AM specific workhorse for
1943 : * estimate_rel_size(). Look there for an explanation of the parameters.
1944 : */
1945 : static inline void
1946 403584 : table_relation_estimate_size(Relation rel, int32 *attr_widths,
1947 : BlockNumber *pages, double *tuples,
1948 : double *allvisfrac)
1949 : {
1950 403584 : rel->rd_tableam->relation_estimate_size(rel, attr_widths, pages, tuples,
1951 : allvisfrac);
1952 403584 : }
1953 :
1954 :
1955 : /* ----------------------------------------------------------------------------
1956 : * Executor related functionality
1957 : * ----------------------------------------------------------------------------
1958 : */
1959 :
1960 : /*
1961 : * Prepare to fetch / check / return tuples as part of a bitmap table scan.
1962 : * `scan` needs to have been started via table_beginscan_bm(). Returns false
1963 : * if there are no more blocks in the bitmap, true otherwise.
1964 : *
1965 : * `lossy_pages` and `exact_pages` are EXPLAIN counters that can be
1966 : * incremented by the table AM to indicate whether or not the block's
1967 : * representation in the bitmap is lossy.
1968 : *
1969 : * `recheck` is set by the table AM to indicate whether or not the tuples
1970 : * from this block should be rechecked.
1971 : *
1972 : * `blockno` is the current block and is set by the table AM and is used by
1973 : * bitmap table scan code to validate that the prefetch block stays ahead of
1974 : * the current block.
1975 : *
1976 : * Note, this is an optionally implemented function, therefore should only be
1977 : * used after verifying the presence (at plan time or such).
1978 : */
1979 : static inline bool
1980 411404 : table_scan_bitmap_next_block(TableScanDesc scan,
1981 : BlockNumber *blockno,
1982 : bool *recheck,
1983 : uint64 *lossy_pages,
1984 : uint64 *exact_pages)
1985 : {
1986 : /*
1987 : * We don't expect direct calls to table_scan_bitmap_next_block with valid
1988 : * CheckXidAlive for catalog or regular tables. See detailed comments in
1989 : * xact.c where these variables are declared.
1990 : */
1991 411404 : if (unlikely(TransactionIdIsValid(CheckXidAlive) && !bsysscan))
1992 0 : elog(ERROR, "unexpected table_scan_bitmap_next_block call during logical decoding");
1993 :
1994 411404 : return scan->rs_rd->rd_tableam->scan_bitmap_next_block(scan,
1995 : blockno, recheck,
1996 : lossy_pages,
1997 : exact_pages);
1998 : }
1999 :
2000 : /*
2001 : * Fetch the next tuple of a bitmap table scan into `slot` and return true if
2002 : * a visible tuple was found, false otherwise.
2003 : * table_scan_bitmap_next_block() needs to previously have selected a
2004 : * block (i.e. returned true), and no previous
2005 : * table_scan_bitmap_next_tuple() for the same block may have
2006 : * returned false.
2007 : */
2008 : static inline bool
2009 6803706 : table_scan_bitmap_next_tuple(TableScanDesc scan,
2010 : TupleTableSlot *slot)
2011 : {
2012 : /*
2013 : * We don't expect direct calls to table_scan_bitmap_next_tuple with valid
2014 : * CheckXidAlive for catalog or regular tables. See detailed comments in
2015 : * xact.c where these variables are declared.
2016 : */
2017 6803706 : if (unlikely(TransactionIdIsValid(CheckXidAlive) && !bsysscan))
2018 0 : elog(ERROR, "unexpected table_scan_bitmap_next_tuple call during logical decoding");
2019 :
2020 6803706 : return scan->rs_rd->rd_tableam->scan_bitmap_next_tuple(scan,
2021 : slot);
2022 : }
2023 :
2024 : /*
2025 : * Prepare to fetch tuples from the next block in a sample scan. Returns false
2026 : * if the sample scan is finished, true otherwise. `scan` needs to have been
2027 : * started via table_beginscan_sampling().
2028 : *
2029 : * This will call the TsmRoutine's NextSampleBlock() callback if necessary
2030 : * (i.e. NextSampleBlock is not NULL), or perform a sequential scan over the
2031 : * underlying relation.
2032 : */
2033 : static inline bool
2034 12910 : table_scan_sample_next_block(TableScanDesc scan,
2035 : struct SampleScanState *scanstate)
2036 : {
2037 : /*
2038 : * We don't expect direct calls to table_scan_sample_next_block with valid
2039 : * CheckXidAlive for catalog or regular tables. See detailed comments in
2040 : * xact.c where these variables are declared.
2041 : */
2042 12910 : if (unlikely(TransactionIdIsValid(CheckXidAlive) && !bsysscan))
2043 0 : elog(ERROR, "unexpected table_scan_sample_next_block call during logical decoding");
2044 12910 : return scan->rs_rd->rd_tableam->scan_sample_next_block(scan, scanstate);
2045 : }
2046 :
2047 : /*
2048 : * Fetch the next sample tuple into `slot` and return true if a visible tuple
2049 : * was found, false otherwise. table_scan_sample_next_block() needs to
2050 : * previously have selected a block (i.e. returned true), and no previous
2051 : * table_scan_sample_next_tuple() for the same block may have returned false.
2052 : *
2053 : * This will call the TsmRoutine's NextSampleTuple() callback.
2054 : */
2055 : static inline bool
2056 253894 : table_scan_sample_next_tuple(TableScanDesc scan,
2057 : struct SampleScanState *scanstate,
2058 : TupleTableSlot *slot)
2059 : {
2060 : /*
2061 : * We don't expect direct calls to table_scan_sample_next_tuple with valid
2062 : * CheckXidAlive for catalog or regular tables. See detailed comments in
2063 : * xact.c where these variables are declared.
2064 : */
2065 253894 : if (unlikely(TransactionIdIsValid(CheckXidAlive) && !bsysscan))
2066 0 : elog(ERROR, "unexpected table_scan_sample_next_tuple call during logical decoding");
2067 253894 : return scan->rs_rd->rd_tableam->scan_sample_next_tuple(scan, scanstate,
2068 : slot);
2069 : }
2070 :
2071 :
2072 : /* ----------------------------------------------------------------------------
2073 : * Functions to make modifications a bit simpler.
2074 : * ----------------------------------------------------------------------------
2075 : */
2076 :
2077 : extern void simple_table_tuple_insert(Relation rel, TupleTableSlot *slot);
2078 : extern void simple_table_tuple_delete(Relation rel, ItemPointer tid,
2079 : Snapshot snapshot);
2080 : extern void simple_table_tuple_update(Relation rel, ItemPointer otid,
2081 : TupleTableSlot *slot, Snapshot snapshot,
2082 : TU_UpdateIndexes *update_indexes);
2083 :
2084 :
2085 : /* ----------------------------------------------------------------------------
2086 : * Helper functions to implement parallel scans for block oriented AMs.
2087 : * ----------------------------------------------------------------------------
2088 : */
2089 :
2090 : extern Size table_block_parallelscan_estimate(Relation rel);
2091 : extern Size table_block_parallelscan_initialize(Relation rel,
2092 : ParallelTableScanDesc pscan);
2093 : extern void table_block_parallelscan_reinitialize(Relation rel,
2094 : ParallelTableScanDesc pscan);
2095 : extern BlockNumber table_block_parallelscan_nextpage(Relation rel,
2096 : ParallelBlockTableScanWorker pbscanwork,
2097 : ParallelBlockTableScanDesc pbscan);
2098 : extern void table_block_parallelscan_startblock_init(Relation rel,
2099 : ParallelBlockTableScanWorker pbscanwork,
2100 : ParallelBlockTableScanDesc pbscan);
2101 :
2102 :
2103 : /* ----------------------------------------------------------------------------
2104 : * Helper functions to implement relation sizing for block oriented AMs.
2105 : * ----------------------------------------------------------------------------
2106 : */
2107 :
2108 : extern uint64 table_block_relation_size(Relation rel, ForkNumber forkNumber);
2109 : extern void table_block_relation_estimate_size(Relation rel,
2110 : int32 *attr_widths,
2111 : BlockNumber *pages,
2112 : double *tuples,
2113 : double *allvisfrac,
2114 : Size overhead_bytes_per_tuple,
2115 : Size usable_bytes_per_page);
2116 :
2117 : /* ----------------------------------------------------------------------------
2118 : * Functions in tableamapi.c
2119 : * ----------------------------------------------------------------------------
2120 : */
2121 :
2122 : extern const TableAmRoutine *GetTableAmRoutine(Oid amhandler);
2123 :
2124 : /* ----------------------------------------------------------------------------
2125 : * Functions in heapam_handler.c
2126 : * ----------------------------------------------------------------------------
2127 : */
2128 :
2129 : extern const TableAmRoutine *GetHeapamTableAmRoutine(void);
2130 :
2131 : #endif /* TABLEAM_H */
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