1
/*-------------------------------------------------------------------------
4
* header file for postgres btree access method implementation.
7
* Portions Copyright (c) 1996-2011, PostgreSQL Global Development Group
8
* Portions Copyright (c) 1994, Regents of the University of California
10
* src/include/access/nbtree.h
12
*-------------------------------------------------------------------------
17
#include "access/genam.h"
18
#include "access/itup.h"
19
#include "access/sdir.h"
20
#include "access/xlog.h"
21
#include "access/xlogutils.h"
24
/* There's room for a 16-bit vacuum cycle ID in BTPageOpaqueData */
25
typedef uint16 BTCycleId;
28
* BTPageOpaqueData -- At the end of every page, we store a pointer
29
* to both siblings in the tree. This is used to do forward/backward
30
* index scans. The next-page link is also critical for recovery when
31
* a search has navigated to the wrong page due to concurrent page splits
32
* or deletions; see src/backend/access/nbtree/README for more info.
34
* In addition, we store the page's btree level (counting upwards from
35
* zero at a leaf page) as well as some flag bits indicating the page type
36
* and status. If the page is deleted, we replace the level with the
37
* next-transaction-ID value indicating when it is safe to reclaim the page.
39
* We also store a "vacuum cycle ID". When a page is split while VACUUM is
40
* processing the index, a nonzero value associated with the VACUUM run is
41
* stored into both halves of the split page. (If VACUUM is not running,
42
* both pages receive zero cycleids.) This allows VACUUM to detect whether
43
* a page was split since it started, with a small probability of false match
44
* if the page was last split some exact multiple of MAX_BT_CYCLE_ID VACUUMs
45
* ago. Also, during a split, the BTP_SPLIT_END flag is cleared in the left
46
* (original) page, and set in the right page, but only if the next page
47
* to its right has a different cycleid.
49
* NOTE: the BTP_LEAF flag bit is redundant since level==0 could be tested
53
typedef struct BTPageOpaqueData
55
BlockNumber btpo_prev; /* left sibling, or P_NONE if leftmost */
56
BlockNumber btpo_next; /* right sibling, or P_NONE if rightmost */
59
uint32 level; /* tree level --- zero for leaf pages */
60
TransactionId xact; /* next transaction ID, if deleted */
62
uint16 btpo_flags; /* flag bits, see below */
63
BTCycleId btpo_cycleid; /* vacuum cycle ID of latest split */
66
typedef BTPageOpaqueData *BTPageOpaque;
68
/* Bits defined in btpo_flags */
69
#define BTP_LEAF (1 << 0) /* leaf page, i.e. not internal page */
70
#define BTP_ROOT (1 << 1) /* root page (has no parent) */
71
#define BTP_DELETED (1 << 2) /* page has been deleted from tree */
72
#define BTP_META (1 << 3) /* meta-page */
73
#define BTP_HALF_DEAD (1 << 4) /* empty, but still in tree */
74
#define BTP_SPLIT_END (1 << 5) /* rightmost page of split group */
75
#define BTP_HAS_GARBAGE (1 << 6) /* page has LP_DEAD tuples */
78
* The max allowed value of a cycle ID is a bit less than 64K. This is
79
* for convenience of pg_filedump and similar utilities: we want to use
80
* the last 2 bytes of special space as an index type indicator, and
81
* restricting cycle ID lets btree use that space for vacuum cycle IDs
82
* while still allowing index type to be identified.
84
#define MAX_BT_CYCLE_ID 0xFF7F
88
* The Meta page is always the first page in the btree index.
89
* Its primary purpose is to point to the location of the btree root page.
90
* We also point to the "fast" root, which is the current effective root;
91
* see README for discussion.
94
typedef struct BTMetaPageData
96
uint32 btm_magic; /* should contain BTREE_MAGIC */
97
uint32 btm_version; /* should contain BTREE_VERSION */
98
BlockNumber btm_root; /* current root location */
99
uint32 btm_level; /* tree level of the root page */
100
BlockNumber btm_fastroot; /* current "fast" root location */
101
uint32 btm_fastlevel; /* tree level of the "fast" root page */
104
#define BTPageGetMeta(p) \
105
((BTMetaPageData *) PageGetContents(p))
107
#define BTREE_METAPAGE 0 /* first page is meta */
108
#define BTREE_MAGIC 0x053162 /* magic number of btree pages */
109
#define BTREE_VERSION 2 /* current version number */
112
* Maximum size of a btree index entry, including its tuple header.
114
* We actually need to be able to fit three items on every page,
115
* so restrict any one item to 1/3 the per-page available space.
117
#define BTMaxItemSize(page) \
118
MAXALIGN_DOWN((PageGetPageSize(page) - \
119
MAXALIGN(SizeOfPageHeaderData + 3*sizeof(ItemIdData)) - \
120
MAXALIGN(sizeof(BTPageOpaqueData))) / 3)
123
* The leaf-page fillfactor defaults to 90% but is user-adjustable.
124
* For pages above the leaf level, we use a fixed 70% fillfactor.
125
* The fillfactor is applied during index build and when splitting
126
* a rightmost page; when splitting non-rightmost pages we try to
127
* divide the data equally.
129
#define BTREE_MIN_FILLFACTOR 10
130
#define BTREE_DEFAULT_FILLFACTOR 90
131
#define BTREE_NONLEAF_FILLFACTOR 70
134
* Test whether two btree entries are "the same".
137
* In addition, we must guarantee that all tuples in the index are unique,
138
* in order to satisfy some assumptions in Lehman and Yao. The way that we
139
* do this is by generating a new OID for every insertion that we do in the
140
* tree. This adds eight bytes to the size of btree index tuples. Note
141
* that we do not use the OID as part of a composite key; the OID only
142
* serves as a unique identifier for a given index tuple (logical position
146
* actually, we must guarantee that all tuples in A LEVEL
147
* are unique, not in ALL INDEX. So, we can use the t_tid
148
* as unique identifier for a given index tuple (logical position
149
* within a level). - vadim 04/09/97
151
#define BTTidSame(i1, i2) \
152
( (i1).ip_blkid.bi_hi == (i2).ip_blkid.bi_hi && \
153
(i1).ip_blkid.bi_lo == (i2).ip_blkid.bi_lo && \
154
(i1).ip_posid == (i2).ip_posid )
155
#define BTEntrySame(i1, i2) \
156
BTTidSame((i1)->t_tid, (i2)->t_tid)
160
* In general, the btree code tries to localize its knowledge about
161
* page layout to a couple of routines. However, we need a special
162
* value to indicate "no page number" in those places where we expect
163
* page numbers. We can use zero for this because we never need to
164
* make a pointer to the metadata page.
170
* Macros to test whether a page is leftmost or rightmost on its tree level,
171
* as well as other state info kept in the opaque data.
173
#define P_LEFTMOST(opaque) ((opaque)->btpo_prev == P_NONE)
174
#define P_RIGHTMOST(opaque) ((opaque)->btpo_next == P_NONE)
175
#define P_ISLEAF(opaque) ((opaque)->btpo_flags & BTP_LEAF)
176
#define P_ISROOT(opaque) ((opaque)->btpo_flags & BTP_ROOT)
177
#define P_ISDELETED(opaque) ((opaque)->btpo_flags & BTP_DELETED)
178
#define P_ISHALFDEAD(opaque) ((opaque)->btpo_flags & BTP_HALF_DEAD)
179
#define P_IGNORE(opaque) ((opaque)->btpo_flags & (BTP_DELETED|BTP_HALF_DEAD))
180
#define P_HAS_GARBAGE(opaque) ((opaque)->btpo_flags & BTP_HAS_GARBAGE)
183
* Lehman and Yao's algorithm requires a ``high key'' on every non-rightmost
184
* page. The high key is not a data key, but gives info about what range of
185
* keys is supposed to be on this page. The high key on a page is required
186
* to be greater than or equal to any data key that appears on the page.
187
* If we find ourselves trying to insert a key > high key, we know we need
188
* to move right (this should only happen if the page was split since we
189
* examined the parent page).
191
* Our insertion algorithm guarantees that we can use the initial least key
192
* on our right sibling as the high key. Once a page is created, its high
193
* key changes only if the page is split.
195
* On a non-rightmost page, the high key lives in item 1 and data items
196
* start in item 2. Rightmost pages have no high key, so we store data
197
* items beginning in item 1.
200
#define P_HIKEY ((OffsetNumber) 1)
201
#define P_FIRSTKEY ((OffsetNumber) 2)
202
#define P_FIRSTDATAKEY(opaque) (P_RIGHTMOST(opaque) ? P_HIKEY : P_FIRSTKEY)
205
* XLOG records for btree operations
207
* XLOG allows to store some information in high 4 bits of log
208
* record xl_info field
210
#define XLOG_BTREE_INSERT_LEAF 0x00 /* add index tuple without split */
211
#define XLOG_BTREE_INSERT_UPPER 0x10 /* same, on a non-leaf page */
212
#define XLOG_BTREE_INSERT_META 0x20 /* same, plus update metapage */
213
#define XLOG_BTREE_SPLIT_L 0x30 /* add index tuple with split */
214
#define XLOG_BTREE_SPLIT_R 0x40 /* as above, new item on right */
215
#define XLOG_BTREE_SPLIT_L_ROOT 0x50 /* add tuple with split of root */
216
#define XLOG_BTREE_SPLIT_R_ROOT 0x60 /* as above, new item on right */
217
#define XLOG_BTREE_DELETE 0x70 /* delete leaf index tuples for a page */
218
#define XLOG_BTREE_DELETE_PAGE 0x80 /* delete an entire page */
219
#define XLOG_BTREE_DELETE_PAGE_META 0x90 /* same, and update metapage */
220
#define XLOG_BTREE_NEWROOT 0xA0 /* new root page */
221
#define XLOG_BTREE_DELETE_PAGE_HALF 0xB0 /* page deletion that makes
222
* parent half-dead */
223
#define XLOG_BTREE_VACUUM 0xC0 /* delete entries on a page during
225
#define XLOG_BTREE_REUSE_PAGE 0xD0 /* old page is about to be reused from
229
* All that we need to find changed index tuple
231
typedef struct xl_btreetid
234
ItemPointerData tid; /* changed tuple id */
238
* All that we need to regenerate the meta-data page
240
typedef struct xl_btree_metadata
244
BlockNumber fastroot;
249
* This is what we need to know about simple (without split) insert.
251
* This data record is used for INSERT_LEAF, INSERT_UPPER, INSERT_META.
252
* Note that INSERT_META implies it's not a leaf page.
254
typedef struct xl_btree_insert
256
xl_btreetid target; /* inserted tuple id */
257
/* BlockNumber downlink field FOLLOWS IF NOT XLOG_BTREE_INSERT_LEAF */
258
/* xl_btree_metadata FOLLOWS IF XLOG_BTREE_INSERT_META */
259
/* INDEX TUPLE FOLLOWS AT END OF STRUCT */
262
#define SizeOfBtreeInsert (offsetof(xl_btreetid, tid) + SizeOfIptrData)
265
* On insert with split, we save all the items going into the right sibling
266
* so that we can restore it completely from the log record. This way takes
267
* less xlog space than the normal approach, because if we did it standardly,
268
* XLogInsert would almost always think the right page is new and store its
269
* whole page image. The left page, however, is handled in the normal
270
* incremental-update fashion.
272
* Note: the four XLOG_BTREE_SPLIT xl_info codes all use this data record.
273
* The _L and _R variants indicate whether the inserted tuple went into the
274
* left or right split page (and thus, whether newitemoff and the new item
275
* are stored or not). The _ROOT variants indicate that we are splitting
276
* the root page, and thus that a newroot record rather than an insert or
277
* split record should follow. Note that a split record never carries a
278
* metapage update --- we'll do that in the parent-level update.
280
typedef struct xl_btree_split
283
BlockNumber leftsib; /* orig page / new left page */
284
BlockNumber rightsib; /* new right page */
285
BlockNumber rnext; /* next block (orig page's rightlink) */
286
uint32 level; /* tree level of page being split */
287
OffsetNumber firstright; /* first item moved to right page */
290
* If level > 0, BlockIdData downlink follows. (We use BlockIdData rather
291
* than BlockNumber for alignment reasons: SizeOfBtreeSplit is only 16-bit
294
* If level > 0, an IndexTuple representing the HIKEY of the left page
295
* follows. We don't need this on leaf pages, because it's the same as
296
* the leftmost key in the new right page. Also, it's suppressed if
297
* XLogInsert chooses to store the left page's whole page image.
299
* In the _L variants, next are OffsetNumber newitemoff and the new item.
300
* (In the _R variants, the new item is one of the right page's tuples.)
301
* The new item, but not newitemoff, is suppressed if XLogInsert chooses
302
* to store the left page's whole page image.
304
* Last are the right page's tuples in the form used by _bt_restore_page.
308
#define SizeOfBtreeSplit (offsetof(xl_btree_split, firstright) + sizeof(OffsetNumber))
311
* This is what we need to know about delete of individual leaf index tuples.
312
* The WAL record can represent deletion of any number of index tuples on a
313
* single index page when *not* executed by VACUUM.
315
typedef struct xl_btree_delete
317
RelFileNode node; /* RelFileNode of the index */
319
RelFileNode hnode; /* RelFileNode of the heap the index currently
323
/* TARGET OFFSET NUMBERS FOLLOW AT THE END */
326
#define SizeOfBtreeDelete (offsetof(xl_btree_delete, nitems) + sizeof(int))
329
* This is what we need to know about page reuse within btree.
331
typedef struct xl_btree_reuse_page
335
TransactionId latestRemovedXid;
336
} xl_btree_reuse_page;
338
#define SizeOfBtreeReusePage (sizeof(xl_btree_reuse_page))
341
* This is what we need to know about vacuum of individual leaf index tuples.
342
* The WAL record can represent deletion of any number of index tuples on a
343
* single index page when executed by VACUUM.
345
* The correctness requirement for applying these changes during recovery is
346
* that we must do one of these two things for every block in the index:
347
* * lock the block for cleanup and apply any required changes
348
* * EnsureBlockUnpinned()
349
* The purpose of this is to ensure that no index scans started before we
350
* finish scanning the index are still running by the time we begin to remove
353
* Any changes to any one block are registered on just one WAL record. All
354
* blocks that we need to run EnsureBlockUnpinned() are listed as a block range
355
* starting from the last block vacuumed through until this one. Individual
356
* block numbers aren't given.
358
* Note that the *last* WAL record in any vacuum of an index is allowed to
359
* have a zero length array of offsets. Earlier records must have at least one.
361
typedef struct xl_btree_vacuum
365
BlockNumber lastBlockVacuumed;
367
/* TARGET OFFSET NUMBERS FOLLOW */
370
#define SizeOfBtreeVacuum (offsetof(xl_btree_vacuum, lastBlockVacuumed) + sizeof(BlockNumber))
373
* This is what we need to know about deletion of a btree page. The target
374
* identifies the tuple removed from the parent page (note that we remove
375
* this tuple's downlink and the *following* tuple's key). Note we do not
376
* store any content for the deleted page --- it is just rewritten as empty
377
* during recovery, apart from resetting the btpo.xact.
379
typedef struct xl_btree_delete_page
381
xl_btreetid target; /* deleted tuple id in parent page */
382
BlockNumber deadblk; /* child block being deleted */
383
BlockNumber leftblk; /* child block's left sibling, if any */
384
BlockNumber rightblk; /* child block's right sibling */
385
TransactionId btpo_xact; /* value of btpo.xact for use in recovery */
386
/* xl_btree_metadata FOLLOWS IF XLOG_BTREE_DELETE_PAGE_META */
387
} xl_btree_delete_page;
389
#define SizeOfBtreeDeletePage (offsetof(xl_btree_delete_page, btpo_xact) + sizeof(TransactionId))
392
* New root log record. There are zero tuples if this is to establish an
393
* empty root, or two if it is the result of splitting an old root.
395
* Note that although this implies rewriting the metadata page, we don't need
396
* an xl_btree_metadata record --- the rootblk and level are sufficient.
398
typedef struct xl_btree_newroot
401
BlockNumber rootblk; /* location of new root */
402
uint32 level; /* its tree level */
403
/* 0 or 2 INDEX TUPLES FOLLOW AT END OF STRUCT */
406
#define SizeOfBtreeNewroot (offsetof(xl_btree_newroot, level) + sizeof(uint32))
410
* Operator strategy numbers for B-tree have been moved to access/skey.h,
411
* because many places need to use them in ScanKeyInit() calls.
413
* The strategy numbers are chosen so that we can commute them by
416
#define BTCommuteStrategyNumber(strat) (BTMaxStrategyNumber + 1 - (strat))
419
* When a new operator class is declared, we require that the user
420
* supply us with an amproc procedure for determining whether, for
421
* two keys a and b, a < b, a = b, or a > b. This routine must
422
* return < 0, 0, > 0, respectively, in these three cases. Since we
423
* only have one such proc in amproc, it's number 1.
426
#define BTORDER_PROC 1
429
* We need to be able to tell the difference between read and write
430
* requests for pages, in order to do locking correctly.
433
#define BT_READ BUFFER_LOCK_SHARE
434
#define BT_WRITE BUFFER_LOCK_EXCLUSIVE
437
* BTStackData -- As we descend a tree, we push the (location, downlink)
438
* pairs from internal pages onto a private stack. If we split a
439
* leaf, we use this stack to walk back up the tree and insert data
440
* into parent pages (and possibly to split them, too). Lehman and
441
* Yao's update algorithm guarantees that under no circumstances can
442
* our private stack give us an irredeemably bad picture up the tree.
443
* Again, see the paper for details.
446
typedef struct BTStackData
448
BlockNumber bts_blkno;
449
OffsetNumber bts_offset;
450
IndexTupleData bts_btentry;
451
struct BTStackData *bts_parent;
454
typedef BTStackData *BTStack;
457
* BTScanOpaqueData is the btree-private state needed for an indexscan.
458
* This consists of preprocessed scan keys (see _bt_preprocess_keys() for
459
* details of the preprocessing), information about the current location
460
* of the scan, and information about the marked location, if any. (We use
461
* BTScanPosData to represent the data needed for each of current and marked
462
* locations.) In addition we can remember some known-killed index entries
463
* that must be marked before we can move off the current page.
465
* Index scans work a page at a time: we pin and read-lock the page, identify
466
* all the matching items on the page and save them in BTScanPosData, then
467
* release the read-lock while returning the items to the caller for
468
* processing. This approach minimizes lock/unlock traffic. Note that we
469
* keep the pin on the index page until the caller is done with all the items
470
* (this is needed for VACUUM synchronization, see nbtree/README). When we
471
* are ready to step to the next page, if the caller has told us any of the
472
* items were killed, we re-lock the page to mark them killed, then unlock.
473
* Finally we drop the pin and step to the next page in the appropriate
477
typedef struct BTScanPosItem /* what we remember about each match */
479
ItemPointerData heapTid; /* TID of referenced heap item */
480
OffsetNumber indexOffset; /* index item's location within page */
483
typedef struct BTScanPosData
485
Buffer buf; /* if valid, the buffer is pinned */
487
BlockNumber nextPage; /* page's right link when we scanned it */
490
* moreLeft and moreRight track whether we think there may be matching
491
* index entries to the left and right of the current page, respectively.
492
* We can clear the appropriate one of these flags when _bt_checkkeys()
493
* returns continuescan = false.
499
* The items array is always ordered in index order (ie, increasing
500
* indexoffset). When scanning backwards it is convenient to fill the
501
* array back-to-front, so we start at the last slot and fill downwards.
502
* Hence we need both a first-valid-entry and a last-valid-entry counter.
503
* itemIndex is a cursor showing which entry was last returned to caller.
505
int firstItem; /* first valid index in items[] */
506
int lastItem; /* last valid index in items[] */
507
int itemIndex; /* current index in items[] */
509
BTScanPosItem items[MaxIndexTuplesPerPage]; /* MUST BE LAST */
512
typedef BTScanPosData *BTScanPos;
514
#define BTScanPosIsValid(scanpos) BufferIsValid((scanpos).buf)
516
typedef struct BTScanOpaqueData
518
/* these fields are set by _bt_preprocess_keys(): */
519
bool qual_ok; /* false if qual can never be satisfied */
520
int numberOfKeys; /* number of preprocessed scan keys */
521
ScanKey keyData; /* array of preprocessed scan keys */
523
/* info about killed items if any (killedItems is NULL if never used) */
524
int *killedItems; /* currPos.items indexes of killed items */
525
int numKilled; /* number of currently stored items */
528
* If the marked position is on the same page as current position, we
529
* don't use markPos, but just keep the marked itemIndex in markItemIndex
530
* (all the rest of currPos is valid for the mark position). Hence, to
531
* determine if there is a mark, first look at markItemIndex, then at
534
int markItemIndex; /* itemIndex, or -1 if not valid */
536
/* keep these last in struct for efficiency */
537
BTScanPosData currPos; /* current position data */
538
BTScanPosData markPos; /* marked position, if any */
541
typedef BTScanOpaqueData *BTScanOpaque;
544
* We use some private sk_flags bits in preprocessed scan keys. We're allowed
545
* to use bits 16-31 (see skey.h). The uppermost bits are copied from the
546
* index's indoption[] array entry for the index attribute.
548
#define SK_BT_REQFWD 0x00010000 /* required to continue forward scan */
549
#define SK_BT_REQBKWD 0x00020000 /* required to continue backward scan */
550
#define SK_BT_INDOPTION_SHIFT 24 /* must clear the above bits */
551
#define SK_BT_DESC (INDOPTION_DESC << SK_BT_INDOPTION_SHIFT)
552
#define SK_BT_NULLS_FIRST (INDOPTION_NULLS_FIRST << SK_BT_INDOPTION_SHIFT)
555
* prototypes for functions in nbtree.c (external entry points for btree)
557
extern Datum btbuild(PG_FUNCTION_ARGS);
558
extern Datum btbuildempty(PG_FUNCTION_ARGS);
559
extern Datum btinsert(PG_FUNCTION_ARGS);
560
extern Datum btbeginscan(PG_FUNCTION_ARGS);
561
extern Datum btgettuple(PG_FUNCTION_ARGS);
562
extern Datum btgetbitmap(PG_FUNCTION_ARGS);
563
extern Datum btrescan(PG_FUNCTION_ARGS);
564
extern Datum btendscan(PG_FUNCTION_ARGS);
565
extern Datum btmarkpos(PG_FUNCTION_ARGS);
566
extern Datum btrestrpos(PG_FUNCTION_ARGS);
567
extern Datum btbulkdelete(PG_FUNCTION_ARGS);
568
extern Datum btvacuumcleanup(PG_FUNCTION_ARGS);
569
extern Datum btoptions(PG_FUNCTION_ARGS);
572
* prototypes for functions in nbtinsert.c
574
extern bool _bt_doinsert(Relation rel, IndexTuple itup,
575
IndexUniqueCheck checkUnique, Relation heapRel);
576
extern Buffer _bt_getstackbuf(Relation rel, BTStack stack, int access);
577
extern void _bt_insert_parent(Relation rel, Buffer buf, Buffer rbuf,
578
BTStack stack, bool is_root, bool is_only);
581
* prototypes for functions in nbtpage.c
583
extern void _bt_initmetapage(Page page, BlockNumber rootbknum, uint32 level);
584
extern Buffer _bt_getroot(Relation rel, int access);
585
extern Buffer _bt_gettrueroot(Relation rel);
586
extern void _bt_checkpage(Relation rel, Buffer buf);
587
extern Buffer _bt_getbuf(Relation rel, BlockNumber blkno, int access);
588
extern Buffer _bt_relandgetbuf(Relation rel, Buffer obuf,
589
BlockNumber blkno, int access);
590
extern void _bt_relbuf(Relation rel, Buffer buf);
591
extern void _bt_pageinit(Page page, Size size);
592
extern bool _bt_page_recyclable(Page page);
593
extern void _bt_delitems_delete(Relation rel, Buffer buf,
594
OffsetNumber *itemnos, int nitems, Relation heapRel);
595
extern void _bt_delitems_vacuum(Relation rel, Buffer buf,
596
OffsetNumber *itemnos, int nitems, BlockNumber lastBlockVacuumed);
597
extern int _bt_pagedel(Relation rel, Buffer buf, BTStack stack);
600
* prototypes for functions in nbtsearch.c
602
extern BTStack _bt_search(Relation rel,
603
int keysz, ScanKey scankey, bool nextkey,
604
Buffer *bufP, int access);
605
extern Buffer _bt_moveright(Relation rel, Buffer buf, int keysz,
606
ScanKey scankey, bool nextkey, int access);
607
extern OffsetNumber _bt_binsrch(Relation rel, Buffer buf, int keysz,
608
ScanKey scankey, bool nextkey);
609
extern int32 _bt_compare(Relation rel, int keysz, ScanKey scankey,
610
Page page, OffsetNumber offnum);
611
extern bool _bt_first(IndexScanDesc scan, ScanDirection dir);
612
extern bool _bt_next(IndexScanDesc scan, ScanDirection dir);
613
extern Buffer _bt_get_endpoint(Relation rel, uint32 level, bool rightmost);
616
* prototypes for functions in nbtutils.c
618
extern ScanKey _bt_mkscankey(Relation rel, IndexTuple itup);
619
extern ScanKey _bt_mkscankey_nodata(Relation rel);
620
extern void _bt_freeskey(ScanKey skey);
621
extern void _bt_freestack(BTStack stack);
622
extern void _bt_preprocess_keys(IndexScanDesc scan);
623
extern bool _bt_checkkeys(IndexScanDesc scan,
624
Page page, OffsetNumber offnum,
625
ScanDirection dir, bool *continuescan);
626
extern void _bt_killitems(IndexScanDesc scan, bool haveLock);
627
extern BTCycleId _bt_vacuum_cycleid(Relation rel);
628
extern BTCycleId _bt_start_vacuum(Relation rel);
629
extern void _bt_end_vacuum(Relation rel);
630
extern void _bt_end_vacuum_callback(int code, Datum arg);
631
extern Size BTreeShmemSize(void);
632
extern void BTreeShmemInit(void);
635
* prototypes for functions in nbtsort.c
637
typedef struct BTSpool BTSpool; /* opaque type known only within nbtsort.c */
639
extern BTSpool *_bt_spoolinit(Relation index, bool isunique, bool isdead);
640
extern void _bt_spooldestroy(BTSpool *btspool);
641
extern void _bt_spool(IndexTuple itup, BTSpool *btspool);
642
extern void _bt_leafbuild(BTSpool *btspool, BTSpool *spool2);
645
* prototypes for functions in nbtxlog.c
647
extern void btree_redo(XLogRecPtr lsn, XLogRecord *record);
648
extern void btree_desc(StringInfo buf, uint8 xl_info, char *rec);
649
extern void btree_xlog_startup(void);
650
extern void btree_xlog_cleanup(void);
651
extern bool btree_safe_restartpoint(void);
653
#endif /* NBTREE_H */
added
removed
src/include/access/nbtree.h
