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1 : /*-------------------------------------------------------------------------
2 : *
3 : * tableam.h
4 : * POSTGRES table access method definitions.
5 : *
6 : *
7 : * Portions Copyright (c) 1996-2025, 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 "commands/vacuum.h"
24 : #include "executor/tuptable.h"
25 : #include "storage/read_stream.h"
26 : #include "utils/rel.h"
27 : #include "utils/snapshot.h"
28 :
29 :
30 : #define DEFAULT_TABLE_ACCESS_METHOD "heap"
31 :
32 : /* GUCs */
33 : extern PGDLLIMPORT char *default_table_access_method;
34 : extern PGDLLIMPORT bool synchronize_seqscans;
35 :
36 :
37 : struct BulkInsertStateData;
38 : struct IndexInfo;
39 : struct SampleScanState;
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 : } ScanOptions;
66 :
67 : /*
68 : * Result codes for table_{update,delete,lock_tuple}, and for visibility
69 : * routines inside table AMs.
70 : */
71 : typedef enum TM_Result
72 : {
73 : /*
74 : * Signals that the action succeeded (i.e. update/delete performed, lock
75 : * was acquired)
76 : */
77 : TM_Ok,
78 :
79 : /* The affected tuple wasn't visible to the relevant snapshot */
80 : TM_Invisible,
81 :
82 : /* The affected tuple was already modified by the calling backend */
83 : TM_SelfModified,
84 :
85 : /*
86 : * The affected tuple was updated by another transaction. This includes
87 : * the case where tuple was moved to another partition.
88 : */
89 : TM_Updated,
90 :
91 : /* The affected tuple was deleted by another transaction */
92 : TM_Deleted,
93 :
94 : /*
95 : * The affected tuple is currently being modified by another session. This
96 : * will only be returned if table_(update/delete/lock_tuple) are
97 : * instructed not to wait.
98 : */
99 : TM_BeingModified,
100 :
101 : /* lock couldn't be acquired, action skipped. Only used by lock_tuple */
102 : TM_WouldBlock,
103 : } TM_Result;
104 :
105 : /*
106 : * Result codes for table_update(..., update_indexes*..).
107 : * Used to determine which indexes to update.
108 : */
109 : typedef enum TU_UpdateIndexes
110 : {
111 : /* No indexed columns were updated (incl. TID addressing of tuple) */
112 : TU_None,
113 :
114 : /* A non-summarizing indexed column was updated, or the TID has changed */
115 : TU_All,
116 :
117 : /* Only summarized columns were updated, TID is unchanged */
118 : TU_Summarizing,
119 : } TU_UpdateIndexes;
120 :
121 : /*
122 : * When table_tuple_update, table_tuple_delete, or table_tuple_lock fail
123 : * because the target tuple is already outdated, they fill in this struct to
124 : * provide information to the caller about what happened.
125 : *
126 : * ctid is the target's ctid link: it is the same as the target's TID if the
127 : * target was deleted, or the location of the replacement tuple if the target
128 : * was updated.
129 : *
130 : * xmax is the outdating transaction's XID. If the caller wants to visit the
131 : * replacement tuple, it must check that this matches before believing the
132 : * replacement is really a match. This is InvalidTransactionId if the target
133 : * was !LP_NORMAL (expected only for a TID retrieved from syscache).
134 : *
135 : * cmax is the outdating command's CID, but only when the failure code is
136 : * TM_SelfModified (i.e., something in the current transaction outdated the
137 : * tuple); otherwise cmax is zero. (We make this restriction because
138 : * HeapTupleHeaderGetCmax doesn't work for tuples outdated in other
139 : * transactions.)
140 : */
141 : typedef struct TM_FailureData
142 : {
143 : ItemPointerData ctid;
144 : TransactionId xmax;
145 : CommandId cmax;
146 : bool traversed;
147 : } TM_FailureData;
148 :
149 : /*
150 : * State used when calling table_index_delete_tuples().
151 : *
152 : * Represents the status of table tuples, referenced by table TID and taken by
153 : * index AM from index tuples. State consists of high level parameters of the
154 : * deletion operation, plus two mutable palloc()'d arrays for information
155 : * about the status of individual table tuples. These are conceptually one
156 : * single array. Using two arrays keeps the TM_IndexDelete struct small,
157 : * which makes sorting the first array (the deltids array) fast.
158 : *
159 : * Some index AM callers perform simple index tuple deletion (by specifying
160 : * bottomup = false), and include only known-dead deltids. These known-dead
161 : * entries are all marked knowndeletable = true directly (typically these are
162 : * TIDs from LP_DEAD-marked index tuples), but that isn't strictly required.
163 : *
164 : * Callers that specify bottomup = true are "bottom-up index deletion"
165 : * callers. The considerations for the tableam are more subtle with these
166 : * callers because they ask the tableam to perform highly speculative work,
167 : * and might only expect the tableam to check a small fraction of all entries.
168 : * Caller is not allowed to specify knowndeletable = true for any entry
169 : * because everything is highly speculative. Bottom-up caller provides
170 : * context and hints to tableam -- see comments below for details on how index
171 : * AMs and tableams should coordinate during bottom-up index deletion.
172 : *
173 : * Simple index deletion callers may ask the tableam to perform speculative
174 : * work, too. This is a little like bottom-up deletion, but not too much.
175 : * The tableam will only perform speculative work when it's practically free
176 : * to do so in passing for simple deletion caller (while always performing
177 : * whatever work is needed to enable knowndeletable/LP_DEAD index tuples to
178 : * be deleted within index AM). This is the real reason why it's possible for
179 : * simple index deletion caller to specify knowndeletable = false up front
180 : * (this means "check if it's possible for me to delete corresponding index
181 : * tuple when it's cheap to do so in passing"). The index AM should only
182 : * include "extra" entries for index tuples whose TIDs point to a table block
183 : * that tableam is expected to have to visit anyway (in the event of a block
184 : * orientated tableam). The tableam isn't strictly obligated to check these
185 : * "extra" TIDs, but a block-based AM should always manage to do so in
186 : * practice.
187 : *
188 : * The final contents of the deltids/status arrays are interesting to callers
189 : * that ask tableam to perform speculative work (i.e. when _any_ items have
190 : * knowndeletable set to false up front). These index AM callers will
191 : * naturally need to consult final state to determine which index tuples are
192 : * in fact deletable.
193 : *
194 : * The index AM can keep track of which index tuple relates to which deltid by
195 : * setting idxoffnum (and/or relying on each entry being uniquely identifiable
196 : * using tid), which is important when the final contents of the array will
197 : * need to be interpreted -- the array can shrink from initial size after
198 : * tableam processing and/or have entries in a new order (tableam may sort
199 : * deltids array for its own reasons). Bottom-up callers may find that final
200 : * ndeltids is 0 on return from call to tableam, in which case no index tuple
201 : * deletions are possible. Simple deletion callers can rely on any entries
202 : * they know to be deletable appearing in the final array as deletable.
203 : */
204 : typedef struct TM_IndexDelete
205 : {
206 : ItemPointerData tid; /* table TID from index tuple */
207 : int16 id; /* Offset into TM_IndexStatus array */
208 : } TM_IndexDelete;
209 :
210 : typedef struct TM_IndexStatus
211 : {
212 : OffsetNumber idxoffnum; /* Index am page offset number */
213 : bool knowndeletable; /* Currently known to be deletable? */
214 :
215 : /* Bottom-up index deletion specific fields follow */
216 : bool promising; /* Promising (duplicate) index tuple? */
217 : int16 freespace; /* Space freed in index if deleted */
218 : } TM_IndexStatus;
219 :
220 : /*
221 : * Index AM/tableam coordination is central to the design of bottom-up index
222 : * deletion. The index AM provides hints about where to look to the tableam
223 : * by marking some entries as "promising". Index AM does this with duplicate
224 : * index tuples that are strongly suspected to be old versions left behind by
225 : * UPDATEs that did not logically modify indexed values. Index AM may find it
226 : * helpful to only mark entries as promising when they're thought to have been
227 : * affected by such an UPDATE in the recent past.
228 : *
229 : * Bottom-up index deletion casts a wide net at first, usually by including
230 : * all TIDs on a target index page. It is up to the tableam to worry about
231 : * the cost of checking transaction status information. The tableam is in
232 : * control, but needs careful guidance from the index AM. Index AM requests
233 : * that bottomupfreespace target be met, while tableam measures progress
234 : * towards that goal by tallying the per-entry freespace value for known
235 : * deletable entries. (All !bottomup callers can just set these space related
236 : * fields to zero.)
237 : */
238 : typedef struct TM_IndexDeleteOp
239 : {
240 : Relation irel; /* Target index relation */
241 : BlockNumber iblknum; /* Index block number (for error reports) */
242 : bool bottomup; /* Bottom-up (not simple) deletion? */
243 : int bottomupfreespace; /* Bottom-up space target */
244 :
245 : /* Mutable per-TID information follows (index AM initializes entries) */
246 : int ndeltids; /* Current # of deltids/status elements */
247 : TM_IndexDelete *deltids;
248 : TM_IndexStatus *status;
249 : } TM_IndexDeleteOp;
250 :
251 : /* "options" flag bits for table_tuple_insert */
252 : /* TABLE_INSERT_SKIP_WAL was 0x0001; RelationNeedsWAL() now governs */
253 : #define TABLE_INSERT_SKIP_FSM 0x0002
254 : #define TABLE_INSERT_FROZEN 0x0004
255 : #define TABLE_INSERT_NO_LOGICAL 0x0008
256 :
257 : /* flag bits for table_tuple_lock */
258 : /* Follow tuples whose update is in progress if lock modes don't conflict */
259 : #define TUPLE_LOCK_FLAG_LOCK_UPDATE_IN_PROGRESS (1 << 0)
260 : /* Follow update chain and lock latest version of tuple */
261 : #define TUPLE_LOCK_FLAG_FIND_LAST_VERSION (1 << 1)
262 :
263 :
264 : /* Typedef for callback function for table_index_build_scan */
265 : typedef void (*IndexBuildCallback) (Relation index,
266 : ItemPointer tid,
267 : Datum *values,
268 : bool *isnull,
269 : bool tupleIsAlive,
270 : void *state);
271 :
272 : /*
273 : * API struct for a table AM. Note this must be allocated in a
274 : * server-lifetime manner, typically as a static const struct, which then gets
275 : * returned by FormData_pg_am.amhandler.
276 : *
277 : * In most cases it's not appropriate to call the callbacks directly, use the
278 : * table_* wrapper functions instead.
279 : *
280 : * GetTableAmRoutine() asserts that required callbacks are filled in, remember
281 : * to update when adding a callback.
282 : */
283 : typedef struct TableAmRoutine
284 : {
285 : /* this must be set to T_TableAmRoutine */
286 : NodeTag type;
287 :
288 :
289 : /* ------------------------------------------------------------------------
290 : * Slot related callbacks.
291 : * ------------------------------------------------------------------------
292 : */
293 :
294 : /*
295 : * Return slot implementation suitable for storing a tuple of this AM.
296 : */
297 : const TupleTableSlotOps *(*slot_callbacks) (Relation rel);
298 :
299 :
300 : /* ------------------------------------------------------------------------
301 : * Table scan callbacks.
302 : * ------------------------------------------------------------------------
303 : */
304 :
305 : /*
306 : * Start a scan of `rel`. The callback has to return a TableScanDesc,
307 : * which will typically be embedded in a larger, AM specific, struct.
308 : *
309 : * If nkeys != 0, the results need to be filtered by those scan keys.
310 : *
311 : * pscan, if not NULL, will have already been initialized with
312 : * parallelscan_initialize(), and has to be for the same relation. Will
313 : * only be set coming from table_beginscan_parallel().
314 : *
315 : * `flags` is a bitmask indicating the type of scan (ScanOptions's
316 : * SO_TYPE_*, currently only one may be specified), options controlling
317 : * the scan's behaviour (ScanOptions's SO_ALLOW_*, several may be
318 : * specified, an AM may ignore unsupported ones) and whether the snapshot
319 : * needs to be deallocated at scan_end (ScanOptions's SO_TEMP_SNAPSHOT).
320 : */
321 : TableScanDesc (*scan_begin) (Relation rel,
322 : Snapshot snapshot,
323 : int nkeys, struct ScanKeyData *key,
324 : ParallelTableScanDesc pscan,
325 : uint32 flags);
326 :
327 : /*
328 : * Release resources and deallocate scan. If TableScanDesc.temp_snap,
329 : * TableScanDesc.rs_snapshot needs to be unregistered.
330 : */
331 : void (*scan_end) (TableScanDesc scan);
332 :
333 : /*
334 : * Restart relation scan. If set_params is set to true, allow_{strat,
335 : * sync, pagemode} (see scan_begin) changes should be taken into account.
336 : */
337 : void (*scan_rescan) (TableScanDesc scan, struct ScanKeyData *key,
338 : bool set_params, bool allow_strat,
339 : bool allow_sync, bool allow_pagemode);
340 :
341 : /*
342 : * Return next tuple from `scan`, store in slot.
343 : */
344 : bool (*scan_getnextslot) (TableScanDesc scan,
345 : ScanDirection direction,
346 : TupleTableSlot *slot);
347 :
348 : /*-----------
349 : * Optional functions to provide scanning for ranges of ItemPointers.
350 : * Implementations must either provide both of these functions, or neither
351 : * of them.
352 : *
353 : * Implementations of scan_set_tidrange must themselves handle
354 : * ItemPointers of any value. i.e, they must handle each of the following:
355 : *
356 : * 1) mintid or maxtid is beyond the end of the table; and
357 : * 2) mintid is above maxtid; and
358 : * 3) item offset for mintid or maxtid is beyond the maximum offset
359 : * allowed by the AM.
360 : *
361 : * Implementations can assume that scan_set_tidrange is always called
362 : * before scan_getnextslot_tidrange or after scan_rescan and before any
363 : * further calls to scan_getnextslot_tidrange.
364 : */
365 : void (*scan_set_tidrange) (TableScanDesc scan,
366 : ItemPointer mintid,
367 : ItemPointer maxtid);
368 :
369 : /*
370 : * Return next tuple from `scan` that's in the range of TIDs defined by
371 : * scan_set_tidrange.
372 : */
373 : bool (*scan_getnextslot_tidrange) (TableScanDesc scan,
374 : ScanDirection direction,
375 : TupleTableSlot *slot);
376 :
377 : /* ------------------------------------------------------------------------
378 : * Parallel table scan related functions.
379 : * ------------------------------------------------------------------------
380 : */
381 :
382 : /*
383 : * Estimate the size of shared memory needed for a parallel scan of this
384 : * relation. The snapshot does not need to be accounted for.
385 : */
386 : Size (*parallelscan_estimate) (Relation rel);
387 :
388 : /*
389 : * Initialize ParallelTableScanDesc for a parallel scan of this relation.
390 : * `pscan` will be sized according to parallelscan_estimate() for the same
391 : * relation.
392 : */
393 : Size (*parallelscan_initialize) (Relation rel,
394 : ParallelTableScanDesc pscan);
395 :
396 : /*
397 : * Reinitialize `pscan` for a new scan. `rel` will be the same relation as
398 : * when `pscan` was initialized by parallelscan_initialize.
399 : */
400 : void (*parallelscan_reinitialize) (Relation rel,
401 : ParallelTableScanDesc pscan);
402 :
403 :
404 : /* ------------------------------------------------------------------------
405 : * Index Scan Callbacks
406 : * ------------------------------------------------------------------------
407 : */
408 :
409 : /*
410 : * Prepare to fetch tuples from the relation, as needed when fetching
411 : * tuples for an index scan. The callback has to return an
412 : * IndexFetchTableData, which the AM will typically embed in a larger
413 : * structure with additional information.
414 : *
415 : * Tuples for an index scan can then be fetched via index_fetch_tuple.
416 : */
417 : struct IndexFetchTableData *(*index_fetch_begin) (Relation rel);
418 :
419 : /*
420 : * Reset index fetch. Typically this will release cross index fetch
421 : * resources held in IndexFetchTableData.
422 : */
423 : void (*index_fetch_reset) (struct IndexFetchTableData *data);
424 :
425 : /*
426 : * Release resources and deallocate index fetch.
427 : */
428 : void (*index_fetch_end) (struct IndexFetchTableData *data);
429 :
430 : /*
431 : * Fetch tuple at `tid` into `slot`, after doing a visibility test
432 : * according to `snapshot`. If a tuple was found and passed the visibility
433 : * test, return true, false otherwise.
434 : *
435 : * Note that AMs that do not necessarily update indexes when indexed
436 : * columns do not change, need to return the current/correct version of
437 : * the tuple that is visible to the snapshot, even if the tid points to an
438 : * older version of the tuple.
439 : *
440 : * *call_again is false on the first call to index_fetch_tuple for a tid.
441 : * If there potentially is another tuple matching the tid, *call_again
442 : * needs to be set to true by index_fetch_tuple, signaling to the caller
443 : * that index_fetch_tuple should be called again for the same tid.
444 : *
445 : * *all_dead, if all_dead is not NULL, should be set to true by
446 : * index_fetch_tuple iff it is guaranteed that no backend needs to see
447 : * that tuple. Index AMs can use that to avoid returning that tid in
448 : * future searches.
449 : */
450 : bool (*index_fetch_tuple) (struct IndexFetchTableData *scan,
451 : ItemPointer tid,
452 : Snapshot snapshot,
453 : TupleTableSlot *slot,
454 : bool *call_again, bool *all_dead);
455 :
456 :
457 : /* ------------------------------------------------------------------------
458 : * Callbacks for non-modifying operations on individual tuples
459 : * ------------------------------------------------------------------------
460 : */
461 :
462 : /*
463 : * Fetch tuple at `tid` into `slot`, after doing a visibility test
464 : * according to `snapshot`. If a tuple was found and passed the visibility
465 : * test, returns true, false otherwise.
466 : */
467 : bool (*tuple_fetch_row_version) (Relation rel,
468 : ItemPointer tid,
469 : Snapshot snapshot,
470 : TupleTableSlot *slot);
471 :
472 : /*
473 : * Is tid valid for a scan of this relation.
474 : */
475 : bool (*tuple_tid_valid) (TableScanDesc scan,
476 : ItemPointer tid);
477 :
478 : /*
479 : * Return the latest version of the tuple at `tid`, by updating `tid` to
480 : * point at the newest version.
481 : */
482 : void (*tuple_get_latest_tid) (TableScanDesc scan,
483 : ItemPointer tid);
484 :
485 : /*
486 : * Does the tuple in `slot` satisfy `snapshot`? The slot needs to be of
487 : * the appropriate type for the AM.
488 : */
489 : bool (*tuple_satisfies_snapshot) (Relation rel,
490 : TupleTableSlot *slot,
491 : Snapshot snapshot);
492 :
493 : /* see table_index_delete_tuples() */
494 : TransactionId (*index_delete_tuples) (Relation rel,
495 : TM_IndexDeleteOp *delstate);
496 :
497 :
498 : /* ------------------------------------------------------------------------
499 : * Manipulations of physical tuples.
500 : * ------------------------------------------------------------------------
501 : */
502 :
503 : /* see table_tuple_insert() for reference about parameters */
504 : void (*tuple_insert) (Relation rel, TupleTableSlot *slot,
505 : CommandId cid, int options,
506 : struct BulkInsertStateData *bistate);
507 :
508 : /* see table_tuple_insert_speculative() for reference about parameters */
509 : void (*tuple_insert_speculative) (Relation rel,
510 : TupleTableSlot *slot,
511 : CommandId cid,
512 : int options,
513 : struct BulkInsertStateData *bistate,
514 : uint32 specToken);
515 :
516 : /* see table_tuple_complete_speculative() for reference about parameters */
517 : void (*tuple_complete_speculative) (Relation rel,
518 : TupleTableSlot *slot,
519 : uint32 specToken,
520 : bool succeeded);
521 :
522 : /* see table_multi_insert() for reference about parameters */
523 : void (*multi_insert) (Relation rel, TupleTableSlot **slots, int nslots,
524 : CommandId cid, int options, struct BulkInsertStateData *bistate);
525 :
526 : /* see table_tuple_delete() for reference about parameters */
527 : TM_Result (*tuple_delete) (Relation rel,
528 : ItemPointer tid,
529 : CommandId cid,
530 : Snapshot snapshot,
531 : Snapshot crosscheck,
532 : bool wait,
533 : TM_FailureData *tmfd,
534 : bool changingPart);
535 :
536 : /* see table_tuple_update() for reference about parameters */
537 : TM_Result (*tuple_update) (Relation rel,
538 : ItemPointer otid,
539 : TupleTableSlot *slot,
540 : CommandId cid,
541 : Snapshot snapshot,
542 : Snapshot crosscheck,
543 : bool wait,
544 : TM_FailureData *tmfd,
545 : LockTupleMode *lockmode,
546 : TU_UpdateIndexes *update_indexes);
547 :
548 : /* see table_tuple_lock() for reference about parameters */
549 : TM_Result (*tuple_lock) (Relation rel,
550 : ItemPointer tid,
551 : Snapshot snapshot,
552 : TupleTableSlot *slot,
553 : CommandId cid,
554 : LockTupleMode mode,
555 : LockWaitPolicy wait_policy,
556 : uint8 flags,
557 : TM_FailureData *tmfd);
558 :
559 : /*
560 : * Perform operations necessary to complete insertions made via
561 : * tuple_insert and multi_insert with a BulkInsertState specified. In-tree
562 : * access methods ceased to use this.
563 : *
564 : * Typically callers of tuple_insert and multi_insert will just pass all
565 : * the flags that apply to them, and each AM has to decide which of them
566 : * make sense for it, and then only take actions in finish_bulk_insert for
567 : * those flags, and ignore others.
568 : *
569 : * Optional callback.
570 : */
571 : void (*finish_bulk_insert) (Relation rel, int options);
572 :
573 :
574 : /* ------------------------------------------------------------------------
575 : * DDL related functionality.
576 : * ------------------------------------------------------------------------
577 : */
578 :
579 : /*
580 : * This callback needs to create new relation storage for `rel`, with
581 : * appropriate durability behaviour for `persistence`.
582 : *
583 : * Note that only the subset of the relcache filled by
584 : * RelationBuildLocalRelation() can be relied upon and that the relation's
585 : * catalog entries will either not yet exist (new relation), or will still
586 : * reference the old relfilelocator.
587 : *
588 : * As output *freezeXid, *minmulti must be set to the values appropriate
589 : * for pg_class.{relfrozenxid, relminmxid}. For AMs that don't need those
590 : * fields to be filled they can be set to InvalidTransactionId and
591 : * InvalidMultiXactId, respectively.
592 : *
593 : * See also table_relation_set_new_filelocator().
594 : */
595 : void (*relation_set_new_filelocator) (Relation rel,
596 : const RelFileLocator *newrlocator,
597 : char persistence,
598 : TransactionId *freezeXid,
599 : MultiXactId *minmulti);
600 :
601 : /*
602 : * This callback needs to remove all contents from `rel`'s current
603 : * relfilelocator. No provisions for transactional behaviour need to be
604 : * made. Often this can be implemented by truncating the underlying
605 : * storage to its minimal size.
606 : *
607 : * See also table_relation_nontransactional_truncate().
608 : */
609 : void (*relation_nontransactional_truncate) (Relation rel);
610 :
611 : /*
612 : * See table_relation_copy_data().
613 : *
614 : * This can typically be implemented by directly copying the underlying
615 : * storage, unless it contains references to the tablespace internally.
616 : */
617 : void (*relation_copy_data) (Relation rel,
618 : const RelFileLocator *newrlocator);
619 :
620 : /* See table_relation_copy_for_cluster() */
621 : void (*relation_copy_for_cluster) (Relation OldTable,
622 : Relation NewTable,
623 : Relation OldIndex,
624 : bool use_sort,
625 : TransactionId OldestXmin,
626 : TransactionId *xid_cutoff,
627 : MultiXactId *multi_cutoff,
628 : double *num_tuples,
629 : double *tups_vacuumed,
630 : double *tups_recently_dead);
631 :
632 : /*
633 : * React to VACUUM command on the relation. The VACUUM can be triggered by
634 : * a user or by autovacuum. The specific actions performed by the AM will
635 : * depend heavily on the individual AM.
636 : *
637 : * On entry a transaction is already established, and the relation is
638 : * locked with a ShareUpdateExclusive lock.
639 : *
640 : * Note that neither VACUUM FULL (and CLUSTER), nor ANALYZE go through
641 : * this routine, even if (for ANALYZE) it is part of the same VACUUM
642 : * command.
643 : *
644 : * There probably, in the future, needs to be a separate callback to
645 : * integrate with autovacuum's scheduling.
646 : */
647 : void (*relation_vacuum) (Relation rel,
648 : const VacuumParams params,
649 : BufferAccessStrategy bstrategy);
650 :
651 : /*
652 : * Prepare to analyze block `blockno` of `scan`. The scan has been started
653 : * with table_beginscan_analyze(). See also
654 : * table_scan_analyze_next_block().
655 : *
656 : * The callback may acquire resources like locks that are held until
657 : * table_scan_analyze_next_tuple() returns false. It e.g. can make sense
658 : * to hold a lock until all tuples on a block have been analyzed by
659 : * scan_analyze_next_tuple.
660 : *
661 : * The callback can return false if the block is not suitable for
662 : * sampling, e.g. because it's a metapage that could never contain tuples.
663 : *
664 : * XXX: This obviously is primarily suited for block-based AMs. It's not
665 : * clear what a good interface for non block based AMs would be, so there
666 : * isn't one yet.
667 : */
668 : bool (*scan_analyze_next_block) (TableScanDesc scan,
669 : ReadStream *stream);
670 :
671 : /*
672 : * See table_scan_analyze_next_tuple().
673 : *
674 : * Not every AM might have a meaningful concept of dead rows, in which
675 : * case it's OK to not increment *deadrows - but note that that may
676 : * influence autovacuum scheduling (see comment for relation_vacuum
677 : * callback).
678 : */
679 : bool (*scan_analyze_next_tuple) (TableScanDesc scan,
680 : TransactionId OldestXmin,
681 : double *liverows,
682 : double *deadrows,
683 : TupleTableSlot *slot);
684 :
685 : /* see table_index_build_range_scan for reference about parameters */
686 : double (*index_build_range_scan) (Relation table_rel,
687 : Relation index_rel,
688 : struct IndexInfo *index_info,
689 : bool allow_sync,
690 : bool anyvisible,
691 : bool progress,
692 : BlockNumber start_blockno,
693 : BlockNumber numblocks,
694 : IndexBuildCallback callback,
695 : void *callback_state,
696 : TableScanDesc scan);
697 :
698 : /* see table_index_validate_scan for reference about parameters */
699 : void (*index_validate_scan) (Relation table_rel,
700 : Relation index_rel,
701 : struct IndexInfo *index_info,
702 : Snapshot snapshot,
703 : struct ValidateIndexState *state);
704 :
705 :
706 : /* ------------------------------------------------------------------------
707 : * Miscellaneous functions.
708 : * ------------------------------------------------------------------------
709 : */
710 :
711 : /*
712 : * See table_relation_size().
713 : *
714 : * Note that currently a few callers use the MAIN_FORKNUM size to figure
715 : * out the range of potentially interesting blocks (brin, analyze). It's
716 : * probable that we'll need to revise the interface for those at some
717 : * point.
718 : */
719 : uint64 (*relation_size) (Relation rel, ForkNumber forkNumber);
720 :
721 :
722 : /*
723 : * This callback should return true if the relation requires a TOAST table
724 : * and false if it does not. It may wish to examine the relation's tuple
725 : * descriptor before making a decision, but if it uses some other method
726 : * of storing large values (or if it does not support them) it can simply
727 : * return false.
728 : */
729 : bool (*relation_needs_toast_table) (Relation rel);
730 :
731 : /*
732 : * This callback should return the OID of the table AM that implements
733 : * TOAST tables for this AM. If the relation_needs_toast_table callback
734 : * always returns false, this callback is not required.
735 : */
736 : Oid (*relation_toast_am) (Relation rel);
737 :
738 : /*
739 : * This callback is invoked when detoasting a value stored in a toast
740 : * table implemented by this AM. See table_relation_fetch_toast_slice()
741 : * for more details.
742 : */
743 : void (*relation_fetch_toast_slice) (Relation toastrel, Oid valueid,
744 : int32 attrsize,
745 : int32 sliceoffset,
746 : int32 slicelength,
747 : struct varlena *result);
748 :
749 :
750 : /* ------------------------------------------------------------------------
751 : * Planner related functions.
752 : * ------------------------------------------------------------------------
753 : */
754 :
755 : /*
756 : * See table_relation_estimate_size().
757 : *
758 : * While block oriented, it shouldn't be too hard for an AM that doesn't
759 : * internally use blocks to convert into a usable representation.
760 : *
761 : * This differs from the relation_size callback by returning size
762 : * estimates (both relation size and tuple count) for planning purposes,
763 : * rather than returning a currently correct estimate.
764 : */
765 : void (*relation_estimate_size) (Relation rel, int32 *attr_widths,
766 : BlockNumber *pages, double *tuples,
767 : double *allvisfrac);
768 :
769 :
770 : /* ------------------------------------------------------------------------
771 : * Executor related functions.
772 : * ------------------------------------------------------------------------
773 : */
774 :
775 : /*
776 : * Fetch the next tuple of a bitmap table scan into `slot` and return true
777 : * if a visible tuple was found, false otherwise.
778 : *
779 : * `lossy_pages` is incremented if the bitmap is lossy for the selected
780 : * page; otherwise, `exact_pages` is incremented. These are tracked for
781 : * display in EXPLAIN ANALYZE output.
782 : *
783 : * Prefetching additional data from the bitmap is left to the table AM.
784 : *
785 : * This is an optional callback.
786 : */
787 : bool (*scan_bitmap_next_tuple) (TableScanDesc scan,
788 : TupleTableSlot *slot,
789 : bool *recheck,
790 : uint64 *lossy_pages,
791 : uint64 *exact_pages);
792 :
793 : /*
794 : * Prepare to fetch tuples from the next block in a sample scan. Return
795 : * false if the sample scan is finished, true otherwise. `scan` was
796 : * started via table_beginscan_sampling().
797 : *
798 : * Typically this will first determine the target block by calling the
799 : * TsmRoutine's NextSampleBlock() callback if not NULL, or alternatively
800 : * perform a sequential scan over all blocks. The determined block is
801 : * then typically read and pinned.
802 : *
803 : * As the TsmRoutine interface is block based, a block needs to be passed
804 : * to NextSampleBlock(). If that's not appropriate for an AM, it
805 : * internally needs to perform mapping between the internal and a block
806 : * based representation.
807 : *
808 : * Note that it's not acceptable to hold deadlock prone resources such as
809 : * lwlocks until scan_sample_next_tuple() has exhausted the tuples on the
810 : * block - the tuple is likely to be returned to an upper query node, and
811 : * the next call could be off a long while. Holding buffer pins and such
812 : * is obviously OK.
813 : *
814 : * Currently it is required to implement this interface, as there's no
815 : * alternative way (contrary e.g. to bitmap scans) to implement sample
816 : * scans. If infeasible to implement, the AM may raise an error.
817 : */
818 : bool (*scan_sample_next_block) (TableScanDesc scan,
819 : struct SampleScanState *scanstate);
820 :
821 : /*
822 : * This callback, only called after scan_sample_next_block has returned
823 : * true, should determine the next tuple to be returned from the selected
824 : * block using the TsmRoutine's NextSampleTuple() callback.
825 : *
826 : * The callback needs to perform visibility checks, and only return
827 : * visible tuples. That obviously can mean calling NextSampleTuple()
828 : * multiple times.
829 : *
830 : * The TsmRoutine interface assumes that there's a maximum offset on a
831 : * given page, so if that doesn't apply to an AM, it needs to emulate that
832 : * assumption somehow.
833 : */
834 : bool (*scan_sample_next_tuple) (TableScanDesc scan,
835 : struct SampleScanState *scanstate,
836 : TupleTableSlot *slot);
837 :
838 : } TableAmRoutine;
839 :
840 :
841 : /* ----------------------------------------------------------------------------
842 : * Slot functions.
843 : * ----------------------------------------------------------------------------
844 : */
845 :
846 : /*
847 : * Returns slot callbacks suitable for holding tuples of the appropriate type
848 : * for the relation. Works for tables, views, foreign tables and partitioned
849 : * tables.
850 : */
851 : extern const TupleTableSlotOps *table_slot_callbacks(Relation relation);
852 :
853 : /*
854 : * Returns slot using the callbacks returned by table_slot_callbacks(), and
855 : * registers it on *reglist.
856 : */
857 : extern TupleTableSlot *table_slot_create(Relation relation, List **reglist);
858 :
859 :
860 : /* ----------------------------------------------------------------------------
861 : * Table scan functions.
862 : * ----------------------------------------------------------------------------
863 : */
864 :
865 : /*
866 : * Start a scan of `rel`. Returned tuples pass a visibility test of
867 : * `snapshot`, and if nkeys != 0, the results are filtered by those scan keys.
868 : */
869 : static inline TableScanDesc
870 209936 : table_beginscan(Relation rel, Snapshot snapshot,
871 : int nkeys, struct ScanKeyData *key)
872 : {
873 209936 : uint32 flags = SO_TYPE_SEQSCAN |
874 : SO_ALLOW_STRAT | SO_ALLOW_SYNC | SO_ALLOW_PAGEMODE;
875 :
876 209936 : return rel->rd_tableam->scan_begin(rel, snapshot, nkeys, key, NULL, flags);
877 : }
878 :
879 : /*
880 : * Like table_beginscan(), but for scanning catalog. It'll automatically use a
881 : * snapshot appropriate for scanning catalog relations.
882 : */
883 : extern TableScanDesc table_beginscan_catalog(Relation relation, int nkeys,
884 : struct ScanKeyData *key);
885 :
886 : /*
887 : * Like table_beginscan(), but table_beginscan_strat() offers an extended API
888 : * that lets the caller control whether a nondefault buffer access strategy
889 : * can be used, and whether syncscan can be chosen (possibly resulting in the
890 : * scan not starting from block zero). Both of these default to true with
891 : * plain table_beginscan.
892 : */
893 : static inline TableScanDesc
894 451220 : table_beginscan_strat(Relation rel, Snapshot snapshot,
895 : int nkeys, struct ScanKeyData *key,
896 : bool allow_strat, bool allow_sync)
897 : {
898 451220 : uint32 flags = SO_TYPE_SEQSCAN | SO_ALLOW_PAGEMODE;
899 :
900 451220 : if (allow_strat)
901 451220 : flags |= SO_ALLOW_STRAT;
902 451220 : if (allow_sync)
903 54898 : flags |= SO_ALLOW_SYNC;
904 :
905 451220 : return rel->rd_tableam->scan_begin(rel, snapshot, nkeys, key, NULL, flags);
906 : }
907 :
908 : /*
909 : * table_beginscan_bm is an alternative entry point for setting up a
910 : * TableScanDesc for a bitmap heap scan. Although that scan technology is
911 : * really quite unlike a standard seqscan, there is just enough commonality to
912 : * make it worth using the same data structure.
913 : */
914 : static inline TableScanDesc
915 16368 : table_beginscan_bm(Relation rel, Snapshot snapshot,
916 : int nkeys, struct ScanKeyData *key)
917 : {
918 16368 : uint32 flags = SO_TYPE_BITMAPSCAN | SO_ALLOW_PAGEMODE;
919 :
920 16368 : return rel->rd_tableam->scan_begin(rel, snapshot, nkeys, key,
921 : NULL, flags);
922 : }
923 :
924 : /*
925 : * table_beginscan_sampling is an alternative entry point for setting up a
926 : * TableScanDesc for a TABLESAMPLE scan. As with bitmap scans, it's worth
927 : * using the same data structure although the behavior is rather different.
928 : * In addition to the options offered by table_beginscan_strat, this call
929 : * also allows control of whether page-mode visibility checking is used.
930 : */
931 : static inline TableScanDesc
932 146 : table_beginscan_sampling(Relation rel, Snapshot snapshot,
933 : int nkeys, struct ScanKeyData *key,
934 : bool allow_strat, bool allow_sync,
935 : bool allow_pagemode)
936 : {
937 146 : uint32 flags = SO_TYPE_SAMPLESCAN;
938 :
939 146 : if (allow_strat)
940 134 : flags |= SO_ALLOW_STRAT;
941 146 : if (allow_sync)
942 66 : flags |= SO_ALLOW_SYNC;
943 146 : if (allow_pagemode)
944 122 : flags |= SO_ALLOW_PAGEMODE;
945 :
946 146 : return rel->rd_tableam->scan_begin(rel, snapshot, nkeys, key, NULL, flags);
947 : }
948 :
949 : /*
950 : * table_beginscan_tid is an alternative entry point for setting up a
951 : * TableScanDesc for a Tid scan. As with bitmap scans, it's worth using
952 : * the same data structure although the behavior is rather different.
953 : */
954 : static inline TableScanDesc
955 762 : table_beginscan_tid(Relation rel, Snapshot snapshot)
956 : {
957 762 : uint32 flags = SO_TYPE_TIDSCAN;
958 :
959 762 : return rel->rd_tableam->scan_begin(rel, snapshot, 0, NULL, NULL, flags);
960 : }
961 :
962 : /*
963 : * table_beginscan_analyze is an alternative entry point for setting up a
964 : * TableScanDesc for an ANALYZE scan. As with bitmap scans, it's worth using
965 : * the same data structure although the behavior is rather different.
966 : */
967 : static inline TableScanDesc
968 17102 : table_beginscan_analyze(Relation rel)
969 : {
970 17102 : uint32 flags = SO_TYPE_ANALYZE;
971 :
972 17102 : return rel->rd_tableam->scan_begin(rel, NULL, 0, NULL, NULL, flags);
973 : }
974 :
975 : /*
976 : * End relation scan.
977 : */
978 : static inline void
979 769906 : table_endscan(TableScanDesc scan)
980 : {
981 769906 : scan->rs_rd->rd_tableam->scan_end(scan);
982 769906 : }
983 :
984 : /*
985 : * Restart a relation scan.
986 : */
987 : static inline void
988 1534952 : table_rescan(TableScanDesc scan,
989 : struct ScanKeyData *key)
990 : {
991 1534952 : scan->rs_rd->rd_tableam->scan_rescan(scan, key, false, false, false, false);
992 1534952 : }
993 :
994 : /*
995 : * Restart a relation scan after changing params.
996 : *
997 : * This call allows changing the buffer strategy, syncscan, and pagemode
998 : * options before starting a fresh scan. Note that although the actual use of
999 : * syncscan might change (effectively, enabling or disabling reporting), the
1000 : * previously selected startblock will be kept.
1001 : */
1002 : static inline void
1003 30 : table_rescan_set_params(TableScanDesc scan, struct ScanKeyData *key,
1004 : bool allow_strat, bool allow_sync, bool allow_pagemode)
1005 : {
1006 30 : scan->rs_rd->rd_tableam->scan_rescan(scan, key, true,
1007 : allow_strat, allow_sync,
1008 : allow_pagemode);
1009 30 : }
1010 :
1011 : /*
1012 : * Return next tuple from `scan`, store in slot.
1013 : */
1014 : static inline bool
1015 99512470 : table_scan_getnextslot(TableScanDesc sscan, ScanDirection direction, TupleTableSlot *slot)
1016 : {
1017 99512470 : slot->tts_tableOid = RelationGetRelid(sscan->rs_rd);
1018 :
1019 : /* We don't expect actual scans using NoMovementScanDirection */
1020 : Assert(direction == ForwardScanDirection ||
1021 : direction == BackwardScanDirection);
1022 :
1023 : /*
1024 : * We don't expect direct calls to table_scan_getnextslot with valid
1025 : * CheckXidAlive for catalog or regular tables. See detailed comments in
1026 : * xact.c where these variables are declared.
1027 : */
1028 99512470 : if (unlikely(TransactionIdIsValid(CheckXidAlive) && !bsysscan))
1029 0 : elog(ERROR, "unexpected table_scan_getnextslot call during logical decoding");
1030 :
1031 99512470 : return sscan->rs_rd->rd_tableam->scan_getnextslot(sscan, direction, slot);
1032 : }
1033 :
1034 : /* ----------------------------------------------------------------------------
1035 : * TID Range scanning related functions.
1036 : * ----------------------------------------------------------------------------
1037 : */
1038 :
1039 : /*
1040 : * table_beginscan_tidrange is the entry point for setting up a TableScanDesc
1041 : * for a TID range scan.
1042 : */
1043 : static inline TableScanDesc
1044 1850 : table_beginscan_tidrange(Relation rel, Snapshot snapshot,
1045 : ItemPointer mintid,
1046 : ItemPointer maxtid)
1047 : {
1048 : TableScanDesc sscan;
1049 1850 : uint32 flags = SO_TYPE_TIDRANGESCAN | SO_ALLOW_PAGEMODE;
1050 :
1051 1850 : sscan = rel->rd_tableam->scan_begin(rel, snapshot, 0, NULL, NULL, flags);
1052 :
1053 : /* Set the range of TIDs to scan */
1054 1850 : sscan->rs_rd->rd_tableam->scan_set_tidrange(sscan, mintid, maxtid);
1055 :
1056 1850 : return sscan;
1057 : }
1058 :
1059 : /*
1060 : * table_rescan_tidrange resets the scan position and sets the minimum and
1061 : * maximum TID range to scan for a TableScanDesc created by
1062 : * table_beginscan_tidrange.
1063 : */
1064 : static inline void
1065 66 : table_rescan_tidrange(TableScanDesc sscan, ItemPointer mintid,
1066 : ItemPointer maxtid)
1067 : {
1068 : /* Ensure table_beginscan_tidrange() was used. */
1069 : Assert((sscan->rs_flags & SO_TYPE_TIDRANGESCAN) != 0);
1070 :
1071 66 : sscan->rs_rd->rd_tableam->scan_rescan(sscan, NULL, false, false, false, false);
1072 66 : sscan->rs_rd->rd_tableam->scan_set_tidrange(sscan, mintid, maxtid);
1073 66 : }
1074 :
1075 : /*
1076 : * Fetch the next tuple from `sscan` for a TID range scan created by
1077 : * table_beginscan_tidrange(). Stores the tuple in `slot` and returns true,
1078 : * or returns false if no more tuples exist in the range.
1079 : */
1080 : static inline bool
1081 8594 : table_scan_getnextslot_tidrange(TableScanDesc sscan, ScanDirection direction,
1082 : TupleTableSlot *slot)
1083 : {
1084 : /* Ensure table_beginscan_tidrange() was used. */
1085 : Assert((sscan->rs_flags & SO_TYPE_TIDRANGESCAN) != 0);
1086 :
1087 : /* We don't expect actual scans using NoMovementScanDirection */
1088 : Assert(direction == ForwardScanDirection ||
1089 : direction == BackwardScanDirection);
1090 :
1091 8594 : return sscan->rs_rd->rd_tableam->scan_getnextslot_tidrange(sscan,
1092 : direction,
1093 : slot);
1094 : }
1095 :
1096 :
1097 : /* ----------------------------------------------------------------------------
1098 : * Parallel table scan related functions.
1099 : * ----------------------------------------------------------------------------
1100 : */
1101 :
1102 : /*
1103 : * Estimate the size of shared memory needed for a parallel scan of this
1104 : * relation.
1105 : */
1106 : extern Size table_parallelscan_estimate(Relation rel, Snapshot snapshot);
1107 :
1108 : /*
1109 : * Initialize ParallelTableScanDesc for a parallel scan of this
1110 : * relation. `pscan` needs to be sized according to parallelscan_estimate()
1111 : * for the same relation. Call this just once in the leader process; then,
1112 : * individual workers attach via table_beginscan_parallel.
1113 : */
1114 : extern void table_parallelscan_initialize(Relation rel,
1115 : ParallelTableScanDesc pscan,
1116 : Snapshot snapshot);
1117 :
1118 : /*
1119 : * Begin a parallel scan. `pscan` needs to have been initialized with
1120 : * table_parallelscan_initialize(), for the same relation. The initialization
1121 : * does not need to have happened in this backend.
1122 : *
1123 : * Caller must hold a suitable lock on the relation.
1124 : */
1125 : extern TableScanDesc table_beginscan_parallel(Relation relation,
1126 : ParallelTableScanDesc pscan);
1127 :
1128 : /*
1129 : * Restart a parallel scan. Call this in the leader process. Caller is
1130 : * responsible for making sure that all workers have finished the scan
1131 : * beforehand.
1132 : */
1133 : static inline void
1134 228 : table_parallelscan_reinitialize(Relation rel, ParallelTableScanDesc pscan)
1135 : {
1136 228 : rel->rd_tableam->parallelscan_reinitialize(rel, pscan);
1137 228 : }
1138 :
1139 :
1140 : /* ----------------------------------------------------------------------------
1141 : * Index scan related functions.
1142 : * ----------------------------------------------------------------------------
1143 : */
1144 :
1145 : /*
1146 : * Prepare to fetch tuples from the relation, as needed when fetching tuples
1147 : * for an index scan.
1148 : *
1149 : * Tuples for an index scan can then be fetched via table_index_fetch_tuple().
1150 : */
1151 : static inline IndexFetchTableData *
1152 27104882 : table_index_fetch_begin(Relation rel)
1153 : {
1154 27104882 : return rel->rd_tableam->index_fetch_begin(rel);
1155 : }
1156 :
1157 : /*
1158 : * Reset index fetch. Typically this will release cross index fetch resources
1159 : * held in IndexFetchTableData.
1160 : */
1161 : static inline void
1162 23514030 : table_index_fetch_reset(struct IndexFetchTableData *scan)
1163 : {
1164 23514030 : scan->rel->rd_tableam->index_fetch_reset(scan);
1165 23514030 : }
1166 :
1167 : /*
1168 : * Release resources and deallocate index fetch.
1169 : */
1170 : static inline void
1171 27103118 : table_index_fetch_end(struct IndexFetchTableData *scan)
1172 : {
1173 27103118 : scan->rel->rd_tableam->index_fetch_end(scan);
1174 27103118 : }
1175 :
1176 : /*
1177 : * Fetches, as part of an index scan, tuple at `tid` into `slot`, after doing
1178 : * a visibility test according to `snapshot`. If a tuple was found and passed
1179 : * the visibility test, returns true, false otherwise. Note that *tid may be
1180 : * modified when we return true (see later remarks on multiple row versions
1181 : * reachable via a single index entry).
1182 : *
1183 : * *call_again needs to be false on the first call to table_index_fetch_tuple() for
1184 : * a tid. If there potentially is another tuple matching the tid, *call_again
1185 : * will be set to true, signaling that table_index_fetch_tuple() should be called
1186 : * again for the same tid.
1187 : *
1188 : * *all_dead, if all_dead is not NULL, will be set to true by
1189 : * table_index_fetch_tuple() iff it is guaranteed that no backend needs to see
1190 : * that tuple. Index AMs can use that to avoid returning that tid in future
1191 : * searches.
1192 : *
1193 : * The difference between this function and table_tuple_fetch_row_version()
1194 : * is that this function returns the currently visible version of a row if
1195 : * the AM supports storing multiple row versions reachable via a single index
1196 : * entry (like heap's HOT). Whereas table_tuple_fetch_row_version() only
1197 : * evaluates the tuple exactly at `tid`. Outside of index entry ->table tuple
1198 : * lookups, table_tuple_fetch_row_version() is what's usually needed.
1199 : */
1200 : static inline bool
1201 38762190 : table_index_fetch_tuple(struct IndexFetchTableData *scan,
1202 : ItemPointer tid,
1203 : Snapshot snapshot,
1204 : TupleTableSlot *slot,
1205 : bool *call_again, bool *all_dead)
1206 : {
1207 : /*
1208 : * We don't expect direct calls to table_index_fetch_tuple with valid
1209 : * CheckXidAlive for catalog or regular tables. See detailed comments in
1210 : * xact.c where these variables are declared.
1211 : */
1212 38762190 : if (unlikely(TransactionIdIsValid(CheckXidAlive) && !bsysscan))
1213 0 : elog(ERROR, "unexpected table_index_fetch_tuple call during logical decoding");
1214 :
1215 38762190 : return scan->rel->rd_tableam->index_fetch_tuple(scan, tid, snapshot,
1216 : slot, call_again,
1217 : all_dead);
1218 : }
1219 :
1220 : /*
1221 : * This is a convenience wrapper around table_index_fetch_tuple() which
1222 : * returns whether there are table tuple items corresponding to an index
1223 : * entry. This likely is only useful to verify if there's a conflict in a
1224 : * unique index.
1225 : */
1226 : extern bool table_index_fetch_tuple_check(Relation rel,
1227 : ItemPointer tid,
1228 : Snapshot snapshot,
1229 : bool *all_dead);
1230 :
1231 :
1232 : /* ------------------------------------------------------------------------
1233 : * Functions for non-modifying operations on individual tuples
1234 : * ------------------------------------------------------------------------
1235 : */
1236 :
1237 :
1238 : /*
1239 : * Fetch tuple at `tid` into `slot`, after doing a visibility test according to
1240 : * `snapshot`. If a tuple was found and passed the visibility test, returns
1241 : * true, false otherwise.
1242 : *
1243 : * See table_index_fetch_tuple's comment about what the difference between
1244 : * these functions is. It is correct to use this function outside of index
1245 : * entry->table tuple lookups.
1246 : */
1247 : static inline bool
1248 354946 : table_tuple_fetch_row_version(Relation rel,
1249 : ItemPointer tid,
1250 : Snapshot snapshot,
1251 : TupleTableSlot *slot)
1252 : {
1253 : /*
1254 : * We don't expect direct calls to table_tuple_fetch_row_version with
1255 : * valid CheckXidAlive for catalog or regular tables. See detailed
1256 : * comments in xact.c where these variables are declared.
1257 : */
1258 354946 : if (unlikely(TransactionIdIsValid(CheckXidAlive) && !bsysscan))
1259 0 : elog(ERROR, "unexpected table_tuple_fetch_row_version call during logical decoding");
1260 :
1261 354946 : return rel->rd_tableam->tuple_fetch_row_version(rel, tid, snapshot, slot);
1262 : }
1263 :
1264 : /*
1265 : * Verify that `tid` is a potentially valid tuple identifier. That doesn't
1266 : * mean that the pointed to row needs to exist or be visible, but that
1267 : * attempting to fetch the row (e.g. with table_tuple_get_latest_tid() or
1268 : * table_tuple_fetch_row_version()) should not error out if called with that
1269 : * tid.
1270 : *
1271 : * `scan` needs to have been started via table_beginscan().
1272 : */
1273 : static inline bool
1274 426 : table_tuple_tid_valid(TableScanDesc scan, ItemPointer tid)
1275 : {
1276 426 : return scan->rs_rd->rd_tableam->tuple_tid_valid(scan, tid);
1277 : }
1278 :
1279 : /*
1280 : * Return the latest version of the tuple at `tid`, by updating `tid` to
1281 : * point at the newest version.
1282 : */
1283 : extern void table_tuple_get_latest_tid(TableScanDesc scan, ItemPointer tid);
1284 :
1285 : /*
1286 : * Return true iff tuple in slot satisfies the snapshot.
1287 : *
1288 : * This assumes the slot's tuple is valid, and of the appropriate type for the
1289 : * AM.
1290 : *
1291 : * Some AMs might modify the data underlying the tuple as a side-effect. If so
1292 : * they ought to mark the relevant buffer dirty.
1293 : */
1294 : static inline bool
1295 229882 : table_tuple_satisfies_snapshot(Relation rel, TupleTableSlot *slot,
1296 : Snapshot snapshot)
1297 : {
1298 229882 : return rel->rd_tableam->tuple_satisfies_snapshot(rel, slot, snapshot);
1299 : }
1300 :
1301 : /*
1302 : * Determine which index tuples are safe to delete based on their table TID.
1303 : *
1304 : * Determines which entries from index AM caller's TM_IndexDeleteOp state
1305 : * point to vacuumable table tuples. Entries that are found by tableam to be
1306 : * vacuumable are naturally safe for index AM to delete, and so get directly
1307 : * marked as deletable. See comments above TM_IndexDelete and comments above
1308 : * TM_IndexDeleteOp for full details.
1309 : *
1310 : * Returns a snapshotConflictHorizon transaction ID that caller places in
1311 : * its index deletion WAL record. This might be used during subsequent REDO
1312 : * of the WAL record when in Hot Standby mode -- a recovery conflict for the
1313 : * index deletion operation might be required on the standby.
1314 : */
1315 : static inline TransactionId
1316 11546 : table_index_delete_tuples(Relation rel, TM_IndexDeleteOp *delstate)
1317 : {
1318 11546 : return rel->rd_tableam->index_delete_tuples(rel, delstate);
1319 : }
1320 :
1321 :
1322 : /* ----------------------------------------------------------------------------
1323 : * Functions for manipulations of physical tuples.
1324 : * ----------------------------------------------------------------------------
1325 : */
1326 :
1327 : /*
1328 : * Insert a tuple from a slot into table AM routine.
1329 : *
1330 : * The options bitmask allows the caller to specify options that may change the
1331 : * behaviour of the AM. The AM will ignore options that it does not support.
1332 : *
1333 : * If the TABLE_INSERT_SKIP_FSM option is specified, AMs are free to not reuse
1334 : * free space in the relation. This can save some cycles when we know the
1335 : * relation is new and doesn't contain useful amounts of free space.
1336 : * TABLE_INSERT_SKIP_FSM is commonly passed directly to
1337 : * RelationGetBufferForTuple. See that method for more information.
1338 : *
1339 : * TABLE_INSERT_FROZEN should only be specified for inserts into
1340 : * relation storage created during the current subtransaction and when
1341 : * there are no prior snapshots or pre-existing portals open.
1342 : * This causes rows to be frozen, which is an MVCC violation and
1343 : * requires explicit options chosen by user.
1344 : *
1345 : * TABLE_INSERT_NO_LOGICAL force-disables the emitting of logical decoding
1346 : * information for the tuple. This should solely be used during table rewrites
1347 : * where RelationIsLogicallyLogged(relation) is not yet accurate for the new
1348 : * relation.
1349 : *
1350 : * Note that most of these options will be applied when inserting into the
1351 : * heap's TOAST table, too, if the tuple requires any out-of-line data.
1352 : *
1353 : * The BulkInsertState object (if any; bistate can be NULL for default
1354 : * behavior) is also just passed through to RelationGetBufferForTuple. If
1355 : * `bistate` is provided, table_finish_bulk_insert() needs to be called.
1356 : *
1357 : * On return the slot's tts_tid and tts_tableOid are updated to reflect the
1358 : * insertion. But note that any toasting of fields within the slot is NOT
1359 : * reflected in the slots contents.
1360 : */
1361 : static inline void
1362 14758272 : table_tuple_insert(Relation rel, TupleTableSlot *slot, CommandId cid,
1363 : int options, struct BulkInsertStateData *bistate)
1364 : {
1365 14758272 : rel->rd_tableam->tuple_insert(rel, slot, cid, options,
1366 : bistate);
1367 14758228 : }
1368 :
1369 : /*
1370 : * Perform a "speculative insertion". These can be backed out afterwards
1371 : * without aborting the whole transaction. Other sessions can wait for the
1372 : * speculative insertion to be confirmed, turning it into a regular tuple, or
1373 : * aborted, as if it never existed. Speculatively inserted tuples behave as
1374 : * "value locks" of short duration, used to implement INSERT .. ON CONFLICT.
1375 : *
1376 : * A transaction having performed a speculative insertion has to either abort,
1377 : * or finish the speculative insertion with
1378 : * table_tuple_complete_speculative(succeeded = ...).
1379 : */
1380 : static inline void
1381 4128 : table_tuple_insert_speculative(Relation rel, TupleTableSlot *slot,
1382 : CommandId cid, int options,
1383 : struct BulkInsertStateData *bistate,
1384 : uint32 specToken)
1385 : {
1386 4128 : rel->rd_tableam->tuple_insert_speculative(rel, slot, cid, options,
1387 : bistate, specToken);
1388 4128 : }
1389 :
1390 : /*
1391 : * Complete "speculative insertion" started in the same transaction. If
1392 : * succeeded is true, the tuple is fully inserted, if false, it's removed.
1393 : */
1394 : static inline void
1395 4122 : table_tuple_complete_speculative(Relation rel, TupleTableSlot *slot,
1396 : uint32 specToken, bool succeeded)
1397 : {
1398 4122 : rel->rd_tableam->tuple_complete_speculative(rel, slot, specToken,
1399 : succeeded);
1400 4122 : }
1401 :
1402 : /*
1403 : * Insert multiple tuples into a table.
1404 : *
1405 : * This is like table_tuple_insert(), but inserts multiple tuples in one
1406 : * operation. That's often faster than calling table_tuple_insert() in a loop,
1407 : * because e.g. the AM can reduce WAL logging and page locking overhead.
1408 : *
1409 : * Except for taking `nslots` tuples as input, and an array of TupleTableSlots
1410 : * in `slots`, the parameters for table_multi_insert() are the same as for
1411 : * table_tuple_insert().
1412 : *
1413 : * Note: this leaks memory into the current memory context. You can create a
1414 : * temporary context before calling this, if that's a problem.
1415 : */
1416 : static inline void
1417 4126 : table_multi_insert(Relation rel, TupleTableSlot **slots, int nslots,
1418 : CommandId cid, int options, struct BulkInsertStateData *bistate)
1419 : {
1420 4126 : rel->rd_tableam->multi_insert(rel, slots, nslots,
1421 : cid, options, bistate);
1422 4126 : }
1423 :
1424 : /*
1425 : * Delete a tuple.
1426 : *
1427 : * NB: do not call this directly unless prepared to deal with
1428 : * concurrent-update conditions. Use simple_table_tuple_delete instead.
1429 : *
1430 : * Input parameters:
1431 : * relation - table to be modified (caller must hold suitable lock)
1432 : * tid - TID of tuple to be deleted
1433 : * cid - delete command ID (used for visibility test, and stored into
1434 : * cmax if successful)
1435 : * crosscheck - if not InvalidSnapshot, also check tuple against this
1436 : * wait - true if should wait for any conflicting update to commit/abort
1437 : * Output parameters:
1438 : * tmfd - filled in failure cases (see below)
1439 : * changingPart - true iff the tuple is being moved to another partition
1440 : * table due to an update of the partition key. Otherwise, false.
1441 : *
1442 : * Normal, successful return value is TM_Ok, which means we did actually
1443 : * delete it. Failure return codes are TM_SelfModified, TM_Updated, and
1444 : * TM_BeingModified (the last only possible if wait == false).
1445 : *
1446 : * In the failure cases, the routine fills *tmfd with the tuple's t_ctid,
1447 : * t_xmax, and, if possible, t_cmax. See comments for struct
1448 : * TM_FailureData for additional info.
1449 : */
1450 : static inline TM_Result
1451 1727816 : table_tuple_delete(Relation rel, ItemPointer tid, CommandId cid,
1452 : Snapshot snapshot, Snapshot crosscheck, bool wait,
1453 : TM_FailureData *tmfd, bool changingPart)
1454 : {
1455 1727816 : return rel->rd_tableam->tuple_delete(rel, tid, cid,
1456 : snapshot, crosscheck,
1457 : wait, tmfd, changingPart);
1458 : }
1459 :
1460 : /*
1461 : * Update a tuple.
1462 : *
1463 : * NB: do not call this directly unless you are prepared to deal with
1464 : * concurrent-update conditions. Use simple_table_tuple_update instead.
1465 : *
1466 : * Input parameters:
1467 : * relation - table to be modified (caller must hold suitable lock)
1468 : * otid - TID of old tuple to be replaced
1469 : * slot - newly constructed tuple data to store
1470 : * cid - update command ID (used for visibility test, and stored into
1471 : * cmax/cmin if successful)
1472 : * crosscheck - if not InvalidSnapshot, also check old tuple against this
1473 : * wait - true if should wait for any conflicting update to commit/abort
1474 : * Output parameters:
1475 : * tmfd - filled in failure cases (see below)
1476 : * lockmode - filled with lock mode acquired on tuple
1477 : * update_indexes - in success cases this is set to true if new index entries
1478 : * are required for this tuple
1479 : *
1480 : * Normal, successful return value is TM_Ok, which means we did actually
1481 : * update it. Failure return codes are TM_SelfModified, TM_Updated, and
1482 : * TM_BeingModified (the last only possible if wait == false).
1483 : *
1484 : * On success, the slot's tts_tid and tts_tableOid are updated to match the new
1485 : * stored tuple; in particular, slot->tts_tid is set to the TID where the
1486 : * new tuple was inserted, and its HEAP_ONLY_TUPLE flag is set iff a HOT
1487 : * update was done. However, any TOAST changes in the new tuple's
1488 : * data are not reflected into *newtup.
1489 : *
1490 : * In the failure cases, the routine fills *tmfd with the tuple's t_ctid,
1491 : * t_xmax, and, if possible, t_cmax. See comments for struct TM_FailureData
1492 : * for additional info.
1493 : */
1494 : static inline TM_Result
1495 387150 : table_tuple_update(Relation rel, ItemPointer otid, TupleTableSlot *slot,
1496 : CommandId cid, Snapshot snapshot, Snapshot crosscheck,
1497 : bool wait, TM_FailureData *tmfd, LockTupleMode *lockmode,
1498 : TU_UpdateIndexes *update_indexes)
1499 : {
1500 387150 : return rel->rd_tableam->tuple_update(rel, otid, slot,
1501 : cid, snapshot, crosscheck,
1502 : wait, tmfd,
1503 : lockmode, update_indexes);
1504 : }
1505 :
1506 : /*
1507 : * Lock a tuple in the specified mode.
1508 : *
1509 : * Input parameters:
1510 : * relation: relation containing tuple (caller must hold suitable lock)
1511 : * tid: TID of tuple to lock
1512 : * snapshot: snapshot to use for visibility determinations
1513 : * cid: current command ID (used for visibility test, and stored into
1514 : * tuple's cmax if lock is successful)
1515 : * mode: lock mode desired
1516 : * wait_policy: what to do if tuple lock is not available
1517 : * flags:
1518 : * If TUPLE_LOCK_FLAG_LOCK_UPDATE_IN_PROGRESS, follow the update chain to
1519 : * also lock descendant tuples if lock modes don't conflict.
1520 : * If TUPLE_LOCK_FLAG_FIND_LAST_VERSION, follow the update chain and lock
1521 : * latest version.
1522 : *
1523 : * Output parameters:
1524 : * *slot: contains the target tuple
1525 : * *tmfd: filled in failure cases (see below)
1526 : *
1527 : * Function result may be:
1528 : * TM_Ok: lock was successfully acquired
1529 : * TM_Invisible: lock failed because tuple was never visible to us
1530 : * TM_SelfModified: lock failed because tuple updated by self
1531 : * TM_Updated: lock failed because tuple updated by other xact
1532 : * TM_Deleted: lock failed because tuple deleted by other xact
1533 : * TM_WouldBlock: lock couldn't be acquired and wait_policy is skip
1534 : *
1535 : * In the failure cases other than TM_Invisible and TM_Deleted, the routine
1536 : * fills *tmfd with the tuple's t_ctid, t_xmax, and, if possible, t_cmax. See
1537 : * comments for struct TM_FailureData for additional info.
1538 : */
1539 : static inline TM_Result
1540 169462 : table_tuple_lock(Relation rel, ItemPointer tid, Snapshot snapshot,
1541 : TupleTableSlot *slot, CommandId cid, LockTupleMode mode,
1542 : LockWaitPolicy wait_policy, uint8 flags,
1543 : TM_FailureData *tmfd)
1544 : {
1545 169462 : return rel->rd_tableam->tuple_lock(rel, tid, snapshot, slot,
1546 : cid, mode, wait_policy,
1547 : flags, tmfd);
1548 : }
1549 :
1550 : /*
1551 : * Perform operations necessary to complete insertions made via
1552 : * tuple_insert and multi_insert with a BulkInsertState specified.
1553 : */
1554 : static inline void
1555 5418 : table_finish_bulk_insert(Relation rel, int options)
1556 : {
1557 : /* optional callback */
1558 5418 : if (rel->rd_tableam && rel->rd_tableam->finish_bulk_insert)
1559 0 : rel->rd_tableam->finish_bulk_insert(rel, options);
1560 5418 : }
1561 :
1562 :
1563 : /* ------------------------------------------------------------------------
1564 : * DDL related functionality.
1565 : * ------------------------------------------------------------------------
1566 : */
1567 :
1568 : /*
1569 : * Create storage for `rel` in `newrlocator`, with persistence set to
1570 : * `persistence`.
1571 : *
1572 : * This is used both during relation creation and various DDL operations to
1573 : * create new rel storage that can be filled from scratch. When creating
1574 : * new storage for an existing relfilelocator, this should be called before the
1575 : * relcache entry has been updated.
1576 : *
1577 : * *freezeXid, *minmulti are set to the xid / multixact horizon for the table
1578 : * that pg_class.{relfrozenxid, relminmxid} have to be set to.
1579 : */
1580 : static inline void
1581 67802 : table_relation_set_new_filelocator(Relation rel,
1582 : const RelFileLocator *newrlocator,
1583 : char persistence,
1584 : TransactionId *freezeXid,
1585 : MultiXactId *minmulti)
1586 : {
1587 67802 : rel->rd_tableam->relation_set_new_filelocator(rel, newrlocator,
1588 : persistence, freezeXid,
1589 : minmulti);
1590 67802 : }
1591 :
1592 : /*
1593 : * Remove all table contents from `rel`, in a non-transactional manner.
1594 : * Non-transactional meaning that there's no need to support rollbacks. This
1595 : * commonly only is used to perform truncations for relation storage created in
1596 : * the current transaction.
1597 : */
1598 : static inline void
1599 624 : table_relation_nontransactional_truncate(Relation rel)
1600 : {
1601 624 : rel->rd_tableam->relation_nontransactional_truncate(rel);
1602 624 : }
1603 :
1604 : /*
1605 : * Copy data from `rel` into the new relfilelocator `newrlocator`. The new
1606 : * relfilelocator may not have storage associated before this function is
1607 : * called. This is only supposed to be used for low level operations like
1608 : * changing a relation's tablespace.
1609 : */
1610 : static inline void
1611 98 : table_relation_copy_data(Relation rel, const RelFileLocator *newrlocator)
1612 : {
1613 98 : rel->rd_tableam->relation_copy_data(rel, newrlocator);
1614 98 : }
1615 :
1616 : /*
1617 : * Copy data from `OldTable` into `NewTable`, as part of a CLUSTER or VACUUM
1618 : * FULL.
1619 : *
1620 : * Additional Input parameters:
1621 : * - use_sort - if true, the table contents are sorted appropriate for
1622 : * `OldIndex`; if false and OldIndex is not InvalidOid, the data is copied
1623 : * in that index's order; if false and OldIndex is InvalidOid, no sorting is
1624 : * performed
1625 : * - OldIndex - see use_sort
1626 : * - OldestXmin - computed by vacuum_get_cutoffs(), even when
1627 : * not needed for the relation's AM
1628 : * - *xid_cutoff - ditto
1629 : * - *multi_cutoff - ditto
1630 : *
1631 : * Output parameters:
1632 : * - *xid_cutoff - rel's new relfrozenxid value, may be invalid
1633 : * - *multi_cutoff - rel's new relminmxid value, may be invalid
1634 : * - *tups_vacuumed - stats, for logging, if appropriate for AM
1635 : * - *tups_recently_dead - stats, for logging, if appropriate for AM
1636 : */
1637 : static inline void
1638 560 : table_relation_copy_for_cluster(Relation OldTable, Relation NewTable,
1639 : Relation OldIndex,
1640 : bool use_sort,
1641 : TransactionId OldestXmin,
1642 : TransactionId *xid_cutoff,
1643 : MultiXactId *multi_cutoff,
1644 : double *num_tuples,
1645 : double *tups_vacuumed,
1646 : double *tups_recently_dead)
1647 : {
1648 560 : OldTable->rd_tableam->relation_copy_for_cluster(OldTable, NewTable, OldIndex,
1649 : use_sort, OldestXmin,
1650 : xid_cutoff, multi_cutoff,
1651 : num_tuples, tups_vacuumed,
1652 : tups_recently_dead);
1653 560 : }
1654 :
1655 : /*
1656 : * Perform VACUUM on the relation. The VACUUM can be triggered by a user or by
1657 : * autovacuum. The specific actions performed by the AM will depend heavily on
1658 : * the individual AM.
1659 : *
1660 : * On entry a transaction needs to already been established, and the
1661 : * table is locked with a ShareUpdateExclusive lock.
1662 : *
1663 : * Note that neither VACUUM FULL (and CLUSTER), nor ANALYZE go through this
1664 : * routine, even if (for ANALYZE) it is part of the same VACUUM command.
1665 : */
1666 : static inline void
1667 247786 : table_relation_vacuum(Relation rel, const VacuumParams params,
1668 : BufferAccessStrategy bstrategy)
1669 : {
1670 247786 : rel->rd_tableam->relation_vacuum(rel, params, bstrategy);
1671 247786 : }
1672 :
1673 : /*
1674 : * Prepare to analyze the next block in the read stream. The scan needs to
1675 : * have been started with table_beginscan_analyze(). Note that this routine
1676 : * might acquire resources like locks that are held until
1677 : * table_scan_analyze_next_tuple() returns false.
1678 : *
1679 : * Returns false if block is unsuitable for sampling, true otherwise.
1680 : */
1681 : static inline bool
1682 153892 : table_scan_analyze_next_block(TableScanDesc scan, ReadStream *stream)
1683 : {
1684 153892 : return scan->rs_rd->rd_tableam->scan_analyze_next_block(scan, stream);
1685 : }
1686 :
1687 : /*
1688 : * Iterate over tuples in the block selected with
1689 : * table_scan_analyze_next_block() (which needs to have returned true, and
1690 : * this routine may not have returned false for the same block before). If a
1691 : * tuple that's suitable for sampling is found, true is returned and a tuple
1692 : * is stored in `slot`.
1693 : *
1694 : * *liverows and *deadrows are incremented according to the encountered
1695 : * tuples.
1696 : */
1697 : static inline bool
1698 10570088 : table_scan_analyze_next_tuple(TableScanDesc scan, TransactionId OldestXmin,
1699 : double *liverows, double *deadrows,
1700 : TupleTableSlot *slot)
1701 : {
1702 10570088 : return scan->rs_rd->rd_tableam->scan_analyze_next_tuple(scan, OldestXmin,
1703 : liverows, deadrows,
1704 : slot);
1705 : }
1706 :
1707 : /*
1708 : * table_index_build_scan - scan the table to find tuples to be indexed
1709 : *
1710 : * This is called back from an access-method-specific index build procedure
1711 : * after the AM has done whatever setup it needs. The parent table relation
1712 : * is scanned to find tuples that should be entered into the index. Each
1713 : * such tuple is passed to the AM's callback routine, which does the right
1714 : * things to add it to the new index. After we return, the AM's index
1715 : * build procedure does whatever cleanup it needs.
1716 : *
1717 : * The total count of live tuples is returned. This is for updating pg_class
1718 : * statistics. (It's annoying not to be able to do that here, but we want to
1719 : * merge that update with others; see index_update_stats.) Note that the
1720 : * index AM itself must keep track of the number of index tuples; we don't do
1721 : * so here because the AM might reject some of the tuples for its own reasons,
1722 : * such as being unable to store NULLs.
1723 : *
1724 : * If 'progress', the PROGRESS_SCAN_BLOCKS_TOTAL counter is updated when
1725 : * starting the scan, and PROGRESS_SCAN_BLOCKS_DONE is updated as we go along.
1726 : *
1727 : * A side effect is to set indexInfo->ii_BrokenHotChain to true if we detect
1728 : * any potentially broken HOT chains. Currently, we set this if there are any
1729 : * RECENTLY_DEAD or DELETE_IN_PROGRESS entries in a HOT chain, without trying
1730 : * very hard to detect whether they're really incompatible with the chain tip.
1731 : * This only really makes sense for heap AM, it might need to be generalized
1732 : * for other AMs later.
1733 : */
1734 : static inline double
1735 55248 : table_index_build_scan(Relation table_rel,
1736 : Relation index_rel,
1737 : struct IndexInfo *index_info,
1738 : bool allow_sync,
1739 : bool progress,
1740 : IndexBuildCallback callback,
1741 : void *callback_state,
1742 : TableScanDesc scan)
1743 : {
1744 55248 : return table_rel->rd_tableam->index_build_range_scan(table_rel,
1745 : index_rel,
1746 : index_info,
1747 : allow_sync,
1748 : false,
1749 : progress,
1750 : 0,
1751 : InvalidBlockNumber,
1752 : callback,
1753 : callback_state,
1754 : scan);
1755 : }
1756 :
1757 : /*
1758 : * As table_index_build_scan(), except that instead of scanning the complete
1759 : * table, only the given number of blocks are scanned. Scan to end-of-rel can
1760 : * be signaled by passing InvalidBlockNumber as numblocks. Note that
1761 : * restricting the range to scan cannot be done when requesting syncscan.
1762 : *
1763 : * When "anyvisible" mode is requested, all tuples visible to any transaction
1764 : * are indexed and counted as live, including those inserted or deleted by
1765 : * transactions that are still in progress.
1766 : */
1767 : static inline double
1768 2938 : table_index_build_range_scan(Relation table_rel,
1769 : Relation index_rel,
1770 : struct IndexInfo *index_info,
1771 : bool allow_sync,
1772 : bool anyvisible,
1773 : bool progress,
1774 : BlockNumber start_blockno,
1775 : BlockNumber numblocks,
1776 : IndexBuildCallback callback,
1777 : void *callback_state,
1778 : TableScanDesc scan)
1779 : {
1780 2938 : return table_rel->rd_tableam->index_build_range_scan(table_rel,
1781 : index_rel,
1782 : index_info,
1783 : allow_sync,
1784 : anyvisible,
1785 : progress,
1786 : start_blockno,
1787 : numblocks,
1788 : callback,
1789 : callback_state,
1790 : scan);
1791 : }
1792 :
1793 : /*
1794 : * table_index_validate_scan - second table scan for concurrent index build
1795 : *
1796 : * See validate_index() for an explanation.
1797 : */
1798 : static inline void
1799 696 : table_index_validate_scan(Relation table_rel,
1800 : Relation index_rel,
1801 : struct IndexInfo *index_info,
1802 : Snapshot snapshot,
1803 : struct ValidateIndexState *state)
1804 : {
1805 696 : table_rel->rd_tableam->index_validate_scan(table_rel,
1806 : index_rel,
1807 : index_info,
1808 : snapshot,
1809 : state);
1810 696 : }
1811 :
1812 :
1813 : /* ----------------------------------------------------------------------------
1814 : * Miscellaneous functionality
1815 : * ----------------------------------------------------------------------------
1816 : */
1817 :
1818 : /*
1819 : * Return the current size of `rel` in bytes. If `forkNumber` is
1820 : * InvalidForkNumber, return the relation's overall size, otherwise the size
1821 : * for the indicated fork.
1822 : *
1823 : * Note that the overall size might not be the equivalent of the sum of sizes
1824 : * for the individual forks for some AMs, e.g. because the AMs storage does
1825 : * not neatly map onto the builtin types of forks.
1826 : */
1827 : static inline uint64
1828 3170220 : table_relation_size(Relation rel, ForkNumber forkNumber)
1829 : {
1830 3170220 : return rel->rd_tableam->relation_size(rel, forkNumber);
1831 : }
1832 :
1833 : /*
1834 : * table_relation_needs_toast_table - does this relation need a toast table?
1835 : */
1836 : static inline bool
1837 46428 : table_relation_needs_toast_table(Relation rel)
1838 : {
1839 46428 : return rel->rd_tableam->relation_needs_toast_table(rel);
1840 : }
1841 :
1842 : /*
1843 : * Return the OID of the AM that should be used to implement the TOAST table
1844 : * for this relation.
1845 : */
1846 : static inline Oid
1847 18026 : table_relation_toast_am(Relation rel)
1848 : {
1849 18026 : return rel->rd_tableam->relation_toast_am(rel);
1850 : }
1851 :
1852 : /*
1853 : * Fetch all or part of a TOAST value from a TOAST table.
1854 : *
1855 : * If this AM is never used to implement a TOAST table, then this callback
1856 : * is not needed. But, if toasted values are ever stored in a table of this
1857 : * type, then you will need this callback.
1858 : *
1859 : * toastrel is the relation in which the toasted value is stored.
1860 : *
1861 : * valueid identifies which toast value is to be fetched. For the heap,
1862 : * this corresponds to the values stored in the chunk_id column.
1863 : *
1864 : * attrsize is the total size of the toast value to be fetched.
1865 : *
1866 : * sliceoffset is the offset within the toast value of the first byte that
1867 : * should be fetched.
1868 : *
1869 : * slicelength is the number of bytes from the toast value that should be
1870 : * fetched.
1871 : *
1872 : * result is caller-allocated space into which the fetched bytes should be
1873 : * stored.
1874 : */
1875 : static inline void
1876 23308 : table_relation_fetch_toast_slice(Relation toastrel, Oid valueid,
1877 : int32 attrsize, int32 sliceoffset,
1878 : int32 slicelength, struct varlena *result)
1879 : {
1880 23308 : toastrel->rd_tableam->relation_fetch_toast_slice(toastrel, valueid,
1881 : attrsize,
1882 : sliceoffset, slicelength,
1883 : result);
1884 23308 : }
1885 :
1886 :
1887 : /* ----------------------------------------------------------------------------
1888 : * Planner related functionality
1889 : * ----------------------------------------------------------------------------
1890 : */
1891 :
1892 : /*
1893 : * Estimate the current size of the relation, as an AM specific workhorse for
1894 : * estimate_rel_size(). Look there for an explanation of the parameters.
1895 : */
1896 : static inline void
1897 448020 : table_relation_estimate_size(Relation rel, int32 *attr_widths,
1898 : BlockNumber *pages, double *tuples,
1899 : double *allvisfrac)
1900 : {
1901 448020 : rel->rd_tableam->relation_estimate_size(rel, attr_widths, pages, tuples,
1902 : allvisfrac);
1903 448020 : }
1904 :
1905 :
1906 : /* ----------------------------------------------------------------------------
1907 : * Executor related functionality
1908 : * ----------------------------------------------------------------------------
1909 : */
1910 :
1911 : /*
1912 : * Fetch / check / return tuples as part of a bitmap table scan. `scan` needs
1913 : * to have been started via table_beginscan_bm(). Fetch the next tuple of a
1914 : * bitmap table scan into `slot` and return true if a visible tuple was found,
1915 : * false otherwise.
1916 : *
1917 : * `recheck` is set by the table AM to indicate whether or not the tuple in
1918 : * `slot` should be rechecked. Tuples from lossy pages will always need to be
1919 : * rechecked, but some non-lossy pages' tuples may also require recheck.
1920 : *
1921 : * `lossy_pages` is incremented if the block's representation in the bitmap is
1922 : * lossy; otherwise, `exact_pages` is incremented.
1923 : */
1924 : static inline bool
1925 6744858 : table_scan_bitmap_next_tuple(TableScanDesc scan,
1926 : TupleTableSlot *slot,
1927 : bool *recheck,
1928 : uint64 *lossy_pages,
1929 : uint64 *exact_pages)
1930 : {
1931 : /*
1932 : * We don't expect direct calls to table_scan_bitmap_next_tuple with valid
1933 : * CheckXidAlive for catalog or regular tables. See detailed comments in
1934 : * xact.c where these variables are declared.
1935 : */
1936 6744858 : if (unlikely(TransactionIdIsValid(CheckXidAlive) && !bsysscan))
1937 0 : elog(ERROR, "unexpected table_scan_bitmap_next_tuple call during logical decoding");
1938 :
1939 6744858 : return scan->rs_rd->rd_tableam->scan_bitmap_next_tuple(scan,
1940 : slot,
1941 : recheck,
1942 : lossy_pages,
1943 : exact_pages);
1944 : }
1945 :
1946 : /*
1947 : * Prepare to fetch tuples from the next block in a sample scan. Returns false
1948 : * if the sample scan is finished, true otherwise. `scan` needs to have been
1949 : * started via table_beginscan_sampling().
1950 : *
1951 : * This will call the TsmRoutine's NextSampleBlock() callback if necessary
1952 : * (i.e. NextSampleBlock is not NULL), or perform a sequential scan over the
1953 : * underlying relation.
1954 : */
1955 : static inline bool
1956 12912 : table_scan_sample_next_block(TableScanDesc scan,
1957 : struct SampleScanState *scanstate)
1958 : {
1959 : /*
1960 : * We don't expect direct calls to table_scan_sample_next_block with valid
1961 : * CheckXidAlive for catalog or regular tables. See detailed comments in
1962 : * xact.c where these variables are declared.
1963 : */
1964 12912 : if (unlikely(TransactionIdIsValid(CheckXidAlive) && !bsysscan))
1965 0 : elog(ERROR, "unexpected table_scan_sample_next_block call during logical decoding");
1966 12912 : return scan->rs_rd->rd_tableam->scan_sample_next_block(scan, scanstate);
1967 : }
1968 :
1969 : /*
1970 : * Fetch the next sample tuple into `slot` and return true if a visible tuple
1971 : * was found, false otherwise. table_scan_sample_next_block() needs to
1972 : * previously have selected a block (i.e. returned true), and no previous
1973 : * table_scan_sample_next_tuple() for the same block may have returned false.
1974 : *
1975 : * This will call the TsmRoutine's NextSampleTuple() callback.
1976 : */
1977 : static inline bool
1978 253896 : table_scan_sample_next_tuple(TableScanDesc scan,
1979 : struct SampleScanState *scanstate,
1980 : TupleTableSlot *slot)
1981 : {
1982 : /*
1983 : * We don't expect direct calls to table_scan_sample_next_tuple with valid
1984 : * CheckXidAlive for catalog or regular tables. See detailed comments in
1985 : * xact.c where these variables are declared.
1986 : */
1987 253896 : if (unlikely(TransactionIdIsValid(CheckXidAlive) && !bsysscan))
1988 0 : elog(ERROR, "unexpected table_scan_sample_next_tuple call during logical decoding");
1989 253896 : return scan->rs_rd->rd_tableam->scan_sample_next_tuple(scan, scanstate,
1990 : slot);
1991 : }
1992 :
1993 :
1994 : /* ----------------------------------------------------------------------------
1995 : * Functions to make modifications a bit simpler.
1996 : * ----------------------------------------------------------------------------
1997 : */
1998 :
1999 : extern void simple_table_tuple_insert(Relation rel, TupleTableSlot *slot);
2000 : extern void simple_table_tuple_delete(Relation rel, ItemPointer tid,
2001 : Snapshot snapshot);
2002 : extern void simple_table_tuple_update(Relation rel, ItemPointer otid,
2003 : TupleTableSlot *slot, Snapshot snapshot,
2004 : TU_UpdateIndexes *update_indexes);
2005 :
2006 :
2007 : /* ----------------------------------------------------------------------------
2008 : * Helper functions to implement parallel scans for block oriented AMs.
2009 : * ----------------------------------------------------------------------------
2010 : */
2011 :
2012 : extern Size table_block_parallelscan_estimate(Relation rel);
2013 : extern Size table_block_parallelscan_initialize(Relation rel,
2014 : ParallelTableScanDesc pscan);
2015 : extern void table_block_parallelscan_reinitialize(Relation rel,
2016 : ParallelTableScanDesc pscan);
2017 : extern BlockNumber table_block_parallelscan_nextpage(Relation rel,
2018 : ParallelBlockTableScanWorker pbscanwork,
2019 : ParallelBlockTableScanDesc pbscan);
2020 : extern void table_block_parallelscan_startblock_init(Relation rel,
2021 : ParallelBlockTableScanWorker pbscanwork,
2022 : ParallelBlockTableScanDesc pbscan);
2023 :
2024 :
2025 : /* ----------------------------------------------------------------------------
2026 : * Helper functions to implement relation sizing for block oriented AMs.
2027 : * ----------------------------------------------------------------------------
2028 : */
2029 :
2030 : extern uint64 table_block_relation_size(Relation rel, ForkNumber forkNumber);
2031 : extern void table_block_relation_estimate_size(Relation rel,
2032 : int32 *attr_widths,
2033 : BlockNumber *pages,
2034 : double *tuples,
2035 : double *allvisfrac,
2036 : Size overhead_bytes_per_tuple,
2037 : Size usable_bytes_per_page);
2038 :
2039 : /* ----------------------------------------------------------------------------
2040 : * Functions in tableamapi.c
2041 : * ----------------------------------------------------------------------------
2042 : */
2043 :
2044 : extern const TableAmRoutine *GetTableAmRoutine(Oid amhandler);
2045 :
2046 : /* ----------------------------------------------------------------------------
2047 : * Functions in heapam_handler.c
2048 : * ----------------------------------------------------------------------------
2049 : */
2050 :
2051 : extern const TableAmRoutine *GetHeapamTableAmRoutine(void);
2052 :
2053 : #endif /* TABLEAM_H */
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