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c8e1ba736b
Backpatch-through: 11
1295 lines
49 KiB
C
1295 lines
49 KiB
C
/*-------------------------------------------------------------------------
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*
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* nbtree.h
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* header file for postgres btree access method implementation.
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*
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*
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* Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* src/include/access/nbtree.h
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*
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*-------------------------------------------------------------------------
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*/
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#ifndef NBTREE_H
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#define NBTREE_H
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#include "access/amapi.h"
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#include "access/itup.h"
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#include "access/sdir.h"
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#include "access/tableam.h"
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#include "access/xlogreader.h"
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#include "catalog/pg_am_d.h"
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#include "catalog/pg_index.h"
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#include "lib/stringinfo.h"
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#include "storage/bufmgr.h"
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#include "storage/shm_toc.h"
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/* There's room for a 16-bit vacuum cycle ID in BTPageOpaqueData */
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typedef uint16 BTCycleId;
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/*
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* BTPageOpaqueData -- At the end of every page, we store a pointer
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* to both siblings in the tree. This is used to do forward/backward
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* index scans. The next-page link is also critical for recovery when
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* a search has navigated to the wrong page due to concurrent page splits
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* or deletions; see src/backend/access/nbtree/README for more info.
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*
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* In addition, we store the page's btree level (counting upwards from
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* zero at a leaf page) as well as some flag bits indicating the page type
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* and status. If the page is deleted, a BTDeletedPageData struct is stored
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* in the page's tuple area, while a standard BTPageOpaqueData struct is
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* stored in the page special area.
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*
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* We also store a "vacuum cycle ID". When a page is split while VACUUM is
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* processing the index, a nonzero value associated with the VACUUM run is
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* stored into both halves of the split page. (If VACUUM is not running,
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* both pages receive zero cycleids.) This allows VACUUM to detect whether
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* a page was split since it started, with a small probability of false match
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* if the page was last split some exact multiple of MAX_BT_CYCLE_ID VACUUMs
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* ago. Also, during a split, the BTP_SPLIT_END flag is cleared in the left
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* (original) page, and set in the right page, but only if the next page
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* to its right has a different cycleid.
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*
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* NOTE: the BTP_LEAF flag bit is redundant since level==0 could be tested
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* instead.
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*
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* NOTE: the btpo_level field used to be a union type in order to allow
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* deleted pages to store a 32-bit safexid in the same field. We now store
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* 64-bit/full safexid values using BTDeletedPageData instead.
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*/
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typedef struct BTPageOpaqueData
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{
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BlockNumber btpo_prev; /* left sibling, or P_NONE if leftmost */
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BlockNumber btpo_next; /* right sibling, or P_NONE if rightmost */
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uint32 btpo_level; /* tree level --- zero for leaf pages */
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uint16 btpo_flags; /* flag bits, see below */
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BTCycleId btpo_cycleid; /* vacuum cycle ID of latest split */
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} BTPageOpaqueData;
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typedef BTPageOpaqueData *BTPageOpaque;
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#define BTPageGetOpaque(page) ((BTPageOpaque) PageGetSpecialPointer(page))
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/* Bits defined in btpo_flags */
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#define BTP_LEAF (1 << 0) /* leaf page, i.e. not internal page */
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#define BTP_ROOT (1 << 1) /* root page (has no parent) */
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#define BTP_DELETED (1 << 2) /* page has been deleted from tree */
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#define BTP_META (1 << 3) /* meta-page */
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#define BTP_HALF_DEAD (1 << 4) /* empty, but still in tree */
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#define BTP_SPLIT_END (1 << 5) /* rightmost page of split group */
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#define BTP_HAS_GARBAGE (1 << 6) /* page has LP_DEAD tuples (deprecated) */
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#define BTP_INCOMPLETE_SPLIT (1 << 7) /* right sibling's downlink is missing */
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#define BTP_HAS_FULLXID (1 << 8) /* contains BTDeletedPageData */
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/*
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* The max allowed value of a cycle ID is a bit less than 64K. This is
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* for convenience of pg_filedump and similar utilities: we want to use
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* the last 2 bytes of special space as an index type indicator, and
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* restricting cycle ID lets btree use that space for vacuum cycle IDs
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* while still allowing index type to be identified.
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*/
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#define MAX_BT_CYCLE_ID 0xFF7F
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/*
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* The Meta page is always the first page in the btree index.
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* Its primary purpose is to point to the location of the btree root page.
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* We also point to the "fast" root, which is the current effective root;
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* see README for discussion.
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*/
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typedef struct BTMetaPageData
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{
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uint32 btm_magic; /* should contain BTREE_MAGIC */
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uint32 btm_version; /* nbtree version (always <= BTREE_VERSION) */
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BlockNumber btm_root; /* current root location */
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uint32 btm_level; /* tree level of the root page */
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BlockNumber btm_fastroot; /* current "fast" root location */
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uint32 btm_fastlevel; /* tree level of the "fast" root page */
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/* remaining fields only valid when btm_version >= BTREE_NOVAC_VERSION */
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/* number of deleted, non-recyclable pages during last cleanup */
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uint32 btm_last_cleanup_num_delpages;
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/* number of heap tuples during last cleanup (deprecated) */
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float8 btm_last_cleanup_num_heap_tuples;
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bool btm_allequalimage; /* are all columns "equalimage"? */
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} BTMetaPageData;
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#define BTPageGetMeta(p) \
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((BTMetaPageData *) PageGetContents(p))
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/*
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* The current Btree version is 4. That's what you'll get when you create
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* a new index.
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*
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* Btree version 3 was used in PostgreSQL v11. It is mostly the same as
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* version 4, but heap TIDs were not part of the keyspace. Index tuples
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* with duplicate keys could be stored in any order. We continue to
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* support reading and writing Btree versions 2 and 3, so that they don't
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* need to be immediately re-indexed at pg_upgrade. In order to get the
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* new heapkeyspace semantics, however, a REINDEX is needed.
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*
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* Deduplication is safe to use when the btm_allequalimage field is set to
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* true. It's safe to read the btm_allequalimage field on version 3, but
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* only version 4 indexes make use of deduplication. Even version 4
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* indexes created on PostgreSQL v12 will need a REINDEX to make use of
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* deduplication, though, since there is no other way to set
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* btm_allequalimage to true (pg_upgrade hasn't been taught to set the
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* metapage field).
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*
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* Btree version 2 is mostly the same as version 3. There are two new
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* fields in the metapage that were introduced in version 3. A version 2
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* metapage will be automatically upgraded to version 3 on the first
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* insert to it. INCLUDE indexes cannot use version 2.
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*/
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#define BTREE_METAPAGE 0 /* first page is meta */
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#define BTREE_MAGIC 0x053162 /* magic number in metapage */
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#define BTREE_VERSION 4 /* current version number */
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#define BTREE_MIN_VERSION 2 /* minimum supported version */
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#define BTREE_NOVAC_VERSION 3 /* version with all meta fields set */
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/*
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* Maximum size of a btree index entry, including its tuple header.
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*
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* We actually need to be able to fit three items on every page,
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* so restrict any one item to 1/3 the per-page available space.
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*
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* There are rare cases where _bt_truncate() will need to enlarge
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* a heap index tuple to make space for a tiebreaker heap TID
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* attribute, which we account for here.
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*/
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#define BTMaxItemSize(page) \
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(MAXALIGN_DOWN((PageGetPageSize(page) - \
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MAXALIGN(SizeOfPageHeaderData + 3*sizeof(ItemIdData)) - \
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MAXALIGN(sizeof(BTPageOpaqueData))) / 3) - \
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MAXALIGN(sizeof(ItemPointerData)))
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#define BTMaxItemSizeNoHeapTid(page) \
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MAXALIGN_DOWN((PageGetPageSize(page) - \
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MAXALIGN(SizeOfPageHeaderData + 3*sizeof(ItemIdData)) - \
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MAXALIGN(sizeof(BTPageOpaqueData))) / 3)
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/*
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* MaxTIDsPerBTreePage is an upper bound on the number of heap TIDs tuples
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* that may be stored on a btree leaf page. It is used to size the
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* per-page temporary buffers.
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*
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* Note: we don't bother considering per-tuple overheads here to keep
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* things simple (value is based on how many elements a single array of
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* heap TIDs must have to fill the space between the page header and
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* special area). The value is slightly higher (i.e. more conservative)
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* than necessary as a result, which is considered acceptable.
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*/
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#define MaxTIDsPerBTreePage \
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(int) ((BLCKSZ - SizeOfPageHeaderData - sizeof(BTPageOpaqueData)) / \
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sizeof(ItemPointerData))
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/*
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* The leaf-page fillfactor defaults to 90% but is user-adjustable.
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* For pages above the leaf level, we use a fixed 70% fillfactor.
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* The fillfactor is applied during index build and when splitting
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* a rightmost page; when splitting non-rightmost pages we try to
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* divide the data equally. When splitting a page that's entirely
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* filled with a single value (duplicates), the effective leaf-page
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* fillfactor is 96%, regardless of whether the page is a rightmost
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* page.
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*/
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#define BTREE_MIN_FILLFACTOR 10
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#define BTREE_DEFAULT_FILLFACTOR 90
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#define BTREE_NONLEAF_FILLFACTOR 70
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#define BTREE_SINGLEVAL_FILLFACTOR 96
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/*
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* In general, the btree code tries to localize its knowledge about
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* page layout to a couple of routines. However, we need a special
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* value to indicate "no page number" in those places where we expect
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* page numbers. We can use zero for this because we never need to
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* make a pointer to the metadata page.
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*/
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#define P_NONE 0
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/*
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* Macros to test whether a page is leftmost or rightmost on its tree level,
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* as well as other state info kept in the opaque data.
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*/
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#define P_LEFTMOST(opaque) ((opaque)->btpo_prev == P_NONE)
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#define P_RIGHTMOST(opaque) ((opaque)->btpo_next == P_NONE)
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#define P_ISLEAF(opaque) (((opaque)->btpo_flags & BTP_LEAF) != 0)
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#define P_ISROOT(opaque) (((opaque)->btpo_flags & BTP_ROOT) != 0)
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#define P_ISDELETED(opaque) (((opaque)->btpo_flags & BTP_DELETED) != 0)
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#define P_ISMETA(opaque) (((opaque)->btpo_flags & BTP_META) != 0)
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#define P_ISHALFDEAD(opaque) (((opaque)->btpo_flags & BTP_HALF_DEAD) != 0)
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#define P_IGNORE(opaque) (((opaque)->btpo_flags & (BTP_DELETED|BTP_HALF_DEAD)) != 0)
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#define P_HAS_GARBAGE(opaque) (((opaque)->btpo_flags & BTP_HAS_GARBAGE) != 0)
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#define P_INCOMPLETE_SPLIT(opaque) (((opaque)->btpo_flags & BTP_INCOMPLETE_SPLIT) != 0)
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#define P_HAS_FULLXID(opaque) (((opaque)->btpo_flags & BTP_HAS_FULLXID) != 0)
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/*
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* BTDeletedPageData is the page contents of a deleted page
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*/
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typedef struct BTDeletedPageData
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{
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FullTransactionId safexid; /* See BTPageIsRecyclable() */
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} BTDeletedPageData;
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static inline void
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BTPageSetDeleted(Page page, FullTransactionId safexid)
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{
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BTPageOpaque opaque;
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PageHeader header;
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BTDeletedPageData *contents;
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opaque = BTPageGetOpaque(page);
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header = ((PageHeader) page);
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opaque->btpo_flags &= ~BTP_HALF_DEAD;
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opaque->btpo_flags |= BTP_DELETED | BTP_HAS_FULLXID;
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header->pd_lower = MAXALIGN(SizeOfPageHeaderData) +
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sizeof(BTDeletedPageData);
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header->pd_upper = header->pd_special;
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/* Set safexid in deleted page */
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contents = ((BTDeletedPageData *) PageGetContents(page));
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contents->safexid = safexid;
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}
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static inline FullTransactionId
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BTPageGetDeleteXid(Page page)
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{
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BTPageOpaque opaque;
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BTDeletedPageData *contents;
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/* We only expect to be called with a deleted page */
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Assert(!PageIsNew(page));
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opaque = BTPageGetOpaque(page);
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Assert(P_ISDELETED(opaque));
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/* pg_upgrade'd deleted page -- must be safe to delete now */
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if (!P_HAS_FULLXID(opaque))
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return FirstNormalFullTransactionId;
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/* Get safexid from deleted page */
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contents = ((BTDeletedPageData *) PageGetContents(page));
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return contents->safexid;
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}
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/*
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* Is an existing page recyclable?
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*
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* This exists to centralize the policy on which deleted pages are now safe to
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* re-use. However, _bt_pendingfsm_finalize() duplicates some of the same
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* logic because it doesn't work directly with pages -- keep the two in sync.
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*
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* Note: PageIsNew() pages are always safe to recycle, but we can't deal with
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* them here (caller is responsible for that case themselves). Caller might
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* well need special handling for new pages anyway.
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*/
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static inline bool
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BTPageIsRecyclable(Page page)
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{
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BTPageOpaque opaque;
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Assert(!PageIsNew(page));
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/* Recycling okay iff page is deleted and safexid is old enough */
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opaque = BTPageGetOpaque(page);
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if (P_ISDELETED(opaque))
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{
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/*
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* The page was deleted, but when? If it was just deleted, a scan
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* might have seen the downlink to it, and will read the page later.
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* As long as that can happen, we must keep the deleted page around as
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* a tombstone.
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*
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* For that check if the deletion XID could still be visible to
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* anyone. If not, then no scan that's still in progress could have
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* seen its downlink, and we can recycle it.
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*
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* XXX: If we had the heap relation we could be more aggressive about
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* recycling deleted pages in non-catalog relations. For now we just
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* pass NULL. That is at least simple and consistent.
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*/
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return GlobalVisCheckRemovableFullXid(NULL, BTPageGetDeleteXid(page));
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}
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return false;
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}
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/*
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* BTVacState and BTPendingFSM are private nbtree.c state used during VACUUM.
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* They are exported for use by page deletion related code in nbtpage.c.
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*/
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typedef struct BTPendingFSM
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{
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BlockNumber target; /* Page deleted by current VACUUM */
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FullTransactionId safexid; /* Page's BTDeletedPageData.safexid */
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} BTPendingFSM;
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typedef struct BTVacState
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{
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IndexVacuumInfo *info;
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IndexBulkDeleteResult *stats;
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IndexBulkDeleteCallback callback;
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void *callback_state;
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BTCycleId cycleid;
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MemoryContext pagedelcontext;
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/*
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* _bt_pendingfsm_finalize() state
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*/
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int bufsize; /* pendingpages space (in # elements) */
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int maxbufsize; /* max bufsize that respects work_mem */
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BTPendingFSM *pendingpages; /* One entry per newly deleted page */
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int npendingpages; /* current # valid pendingpages */
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} BTVacState;
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/*
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* Lehman and Yao's algorithm requires a ``high key'' on every non-rightmost
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* page. The high key is not a tuple that is used to visit the heap. It is
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* a pivot tuple (see "Notes on B-Tree tuple format" below for definition).
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* The high key on a page is required to be greater than or equal to any
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* other key that appears on the page. If we find ourselves trying to
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* insert a key that is strictly > high key, we know we need to move right
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* (this should only happen if the page was split since we examined the
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* parent page).
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*
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* Our insertion algorithm guarantees that we can use the initial least key
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* on our right sibling as the high key. Once a page is created, its high
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* key changes only if the page is split.
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*
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* On a non-rightmost page, the high key lives in item 1 and data items
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* start in item 2. Rightmost pages have no high key, so we store data
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* items beginning in item 1.
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*/
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#define P_HIKEY ((OffsetNumber) 1)
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#define P_FIRSTKEY ((OffsetNumber) 2)
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#define P_FIRSTDATAKEY(opaque) (P_RIGHTMOST(opaque) ? P_HIKEY : P_FIRSTKEY)
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/*
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* Notes on B-Tree tuple format, and key and non-key attributes:
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*
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* INCLUDE B-Tree indexes have non-key attributes. These are extra
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* attributes that may be returned by index-only scans, but do not influence
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* the order of items in the index (formally, non-key attributes are not
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* considered to be part of the key space). Non-key attributes are only
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* present in leaf index tuples whose item pointers actually point to heap
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* tuples (non-pivot tuples). _bt_check_natts() enforces the rules
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* described here.
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*
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* Non-pivot tuple format (plain/non-posting variant):
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*
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* t_tid | t_info | key values | INCLUDE columns, if any
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*
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* t_tid points to the heap TID, which is a tiebreaker key column as of
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* BTREE_VERSION 4.
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*
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* Non-pivot tuples complement pivot tuples, which only have key columns.
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* The sole purpose of pivot tuples is to represent how the key space is
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* separated. In general, any B-Tree index that has more than one level
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* (i.e. any index that does not just consist of a metapage and a single
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* leaf root page) must have some number of pivot tuples, since pivot
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* tuples are used for traversing the tree. Suffix truncation can omit
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* trailing key columns when a new pivot is formed, which makes minus
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* infinity their logical value. Since BTREE_VERSION 4 indexes treat heap
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* TID as a trailing key column that ensures that all index tuples are
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* physically unique, it is necessary to represent heap TID as a trailing
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* key column in pivot tuples, though very often this can be truncated
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* away, just like any other key column. (Actually, the heap TID is
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* omitted rather than truncated, since its representation is different to
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* the non-pivot representation.)
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*
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* Pivot tuple format:
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*
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* t_tid | t_info | key values | [heap TID]
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*
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* We store the number of columns present inside pivot tuples by abusing
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* their t_tid offset field, since pivot tuples never need to store a real
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* offset (pivot tuples generally store a downlink in t_tid, though). The
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* offset field only stores the number of columns/attributes when the
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* INDEX_ALT_TID_MASK bit is set, which doesn't count the trailing heap
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* TID column sometimes stored in pivot tuples -- that's represented by
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* the presence of BT_PIVOT_HEAP_TID_ATTR. The INDEX_ALT_TID_MASK bit in
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* t_info is always set on BTREE_VERSION 4 pivot tuples, since
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* BTreeTupleIsPivot() must work reliably on heapkeyspace versions.
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*
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* In version 2 or version 3 (!heapkeyspace) indexes, INDEX_ALT_TID_MASK
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* might not be set in pivot tuples. BTreeTupleIsPivot() won't work
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* reliably as a result. The number of columns stored is implicitly the
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* same as the number of columns in the index, just like any non-pivot
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* tuple. (The number of columns stored should not vary, since suffix
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* truncation of key columns is unsafe within any !heapkeyspace index.)
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*
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* The 12 least significant bits from t_tid's offset number are used to
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* represent the number of key columns within a pivot tuple. This leaves 4
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* status bits (BT_STATUS_OFFSET_MASK bits), which are shared by all tuples
|
|
* that have the INDEX_ALT_TID_MASK bit set (set in t_info) to store basic
|
|
* tuple metadata. BTreeTupleIsPivot() and BTreeTupleIsPosting() use the
|
|
* BT_STATUS_OFFSET_MASK bits.
|
|
*
|
|
* Sometimes non-pivot tuples also use a representation that repurposes
|
|
* t_tid to store metadata rather than a TID. PostgreSQL v13 introduced a
|
|
* new non-pivot tuple format to support deduplication: posting list
|
|
* tuples. Deduplication merges together multiple equal non-pivot tuples
|
|
* into a logically equivalent, space efficient representation. A posting
|
|
* list is an array of ItemPointerData elements. Non-pivot tuples are
|
|
* merged together to form posting list tuples lazily, at the point where
|
|
* we'd otherwise have to split a leaf page.
|
|
*
|
|
* Posting tuple format (alternative non-pivot tuple representation):
|
|
*
|
|
* t_tid | t_info | key values | posting list (TID array)
|
|
*
|
|
* Posting list tuples are recognized as such by having the
|
|
* INDEX_ALT_TID_MASK status bit set in t_info and the BT_IS_POSTING status
|
|
* bit set in t_tid's offset number. These flags redefine the content of
|
|
* the posting tuple's t_tid to store the location of the posting list
|
|
* (instead of a block number), as well as the total number of heap TIDs
|
|
* present in the tuple (instead of a real offset number).
|
|
*
|
|
* The 12 least significant bits from t_tid's offset number are used to
|
|
* represent the number of heap TIDs present in the tuple, leaving 4 status
|
|
* bits (the BT_STATUS_OFFSET_MASK bits). Like any non-pivot tuple, the
|
|
* number of columns stored is always implicitly the total number in the
|
|
* index (in practice there can never be non-key columns stored, since
|
|
* deduplication is not supported with INCLUDE indexes).
|
|
*/
|
|
#define INDEX_ALT_TID_MASK INDEX_AM_RESERVED_BIT
|
|
|
|
/* Item pointer offset bit masks */
|
|
#define BT_OFFSET_MASK 0x0FFF
|
|
#define BT_STATUS_OFFSET_MASK 0xF000
|
|
/* BT_STATUS_OFFSET_MASK status bits */
|
|
#define BT_PIVOT_HEAP_TID_ATTR 0x1000
|
|
#define BT_IS_POSTING 0x2000
|
|
|
|
/*
|
|
* Mask allocated for number of keys in index tuple must be able to fit
|
|
* maximum possible number of index attributes
|
|
*/
|
|
StaticAssertDecl(BT_OFFSET_MASK >= INDEX_MAX_KEYS,
|
|
"BT_OFFSET_MASK can't fit INDEX_MAX_KEYS");
|
|
|
|
/*
|
|
* Note: BTreeTupleIsPivot() can have false negatives (but not false
|
|
* positives) when used with !heapkeyspace indexes
|
|
*/
|
|
static inline bool
|
|
BTreeTupleIsPivot(IndexTuple itup)
|
|
{
|
|
if ((itup->t_info & INDEX_ALT_TID_MASK) == 0)
|
|
return false;
|
|
/* absence of BT_IS_POSTING in offset number indicates pivot tuple */
|
|
if ((ItemPointerGetOffsetNumberNoCheck(&itup->t_tid) & BT_IS_POSTING) != 0)
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
static inline bool
|
|
BTreeTupleIsPosting(IndexTuple itup)
|
|
{
|
|
if ((itup->t_info & INDEX_ALT_TID_MASK) == 0)
|
|
return false;
|
|
/* presence of BT_IS_POSTING in offset number indicates posting tuple */
|
|
if ((ItemPointerGetOffsetNumberNoCheck(&itup->t_tid) & BT_IS_POSTING) == 0)
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
static inline void
|
|
BTreeTupleSetPosting(IndexTuple itup, uint16 nhtids, int postingoffset)
|
|
{
|
|
Assert(nhtids > 1);
|
|
Assert((nhtids & BT_STATUS_OFFSET_MASK) == 0);
|
|
Assert((size_t) postingoffset == MAXALIGN(postingoffset));
|
|
Assert(postingoffset < INDEX_SIZE_MASK);
|
|
Assert(!BTreeTupleIsPivot(itup));
|
|
|
|
itup->t_info |= INDEX_ALT_TID_MASK;
|
|
ItemPointerSetOffsetNumber(&itup->t_tid, (nhtids | BT_IS_POSTING));
|
|
ItemPointerSetBlockNumber(&itup->t_tid, postingoffset);
|
|
}
|
|
|
|
static inline uint16
|
|
BTreeTupleGetNPosting(IndexTuple posting)
|
|
{
|
|
OffsetNumber existing;
|
|
|
|
Assert(BTreeTupleIsPosting(posting));
|
|
|
|
existing = ItemPointerGetOffsetNumberNoCheck(&posting->t_tid);
|
|
return (existing & BT_OFFSET_MASK);
|
|
}
|
|
|
|
static inline uint32
|
|
BTreeTupleGetPostingOffset(IndexTuple posting)
|
|
{
|
|
Assert(BTreeTupleIsPosting(posting));
|
|
|
|
return ItemPointerGetBlockNumberNoCheck(&posting->t_tid);
|
|
}
|
|
|
|
static inline ItemPointer
|
|
BTreeTupleGetPosting(IndexTuple posting)
|
|
{
|
|
return (ItemPointer) ((char *) posting +
|
|
BTreeTupleGetPostingOffset(posting));
|
|
}
|
|
|
|
static inline ItemPointer
|
|
BTreeTupleGetPostingN(IndexTuple posting, int n)
|
|
{
|
|
return BTreeTupleGetPosting(posting) + n;
|
|
}
|
|
|
|
/*
|
|
* Get/set downlink block number in pivot tuple.
|
|
*
|
|
* Note: Cannot assert that tuple is a pivot tuple. If we did so then
|
|
* !heapkeyspace indexes would exhibit false positive assertion failures.
|
|
*/
|
|
static inline BlockNumber
|
|
BTreeTupleGetDownLink(IndexTuple pivot)
|
|
{
|
|
return ItemPointerGetBlockNumberNoCheck(&pivot->t_tid);
|
|
}
|
|
|
|
static inline void
|
|
BTreeTupleSetDownLink(IndexTuple pivot, BlockNumber blkno)
|
|
{
|
|
ItemPointerSetBlockNumber(&pivot->t_tid, blkno);
|
|
}
|
|
|
|
/*
|
|
* Get number of attributes within tuple.
|
|
*
|
|
* Note that this does not include an implicit tiebreaker heap TID
|
|
* attribute, if any. Note also that the number of key attributes must be
|
|
* explicitly represented in all heapkeyspace pivot tuples.
|
|
*
|
|
* Note: This is defined as a macro rather than an inline function to
|
|
* avoid including rel.h.
|
|
*/
|
|
#define BTreeTupleGetNAtts(itup, rel) \
|
|
( \
|
|
(BTreeTupleIsPivot(itup)) ? \
|
|
( \
|
|
ItemPointerGetOffsetNumberNoCheck(&(itup)->t_tid) & BT_OFFSET_MASK \
|
|
) \
|
|
: \
|
|
IndexRelationGetNumberOfAttributes(rel) \
|
|
)
|
|
|
|
/*
|
|
* Set number of key attributes in tuple.
|
|
*
|
|
* The heap TID tiebreaker attribute bit may also be set here, indicating that
|
|
* a heap TID value will be stored at the end of the tuple (i.e. using the
|
|
* special pivot tuple representation).
|
|
*/
|
|
static inline void
|
|
BTreeTupleSetNAtts(IndexTuple itup, uint16 nkeyatts, bool heaptid)
|
|
{
|
|
Assert(nkeyatts <= INDEX_MAX_KEYS);
|
|
Assert((nkeyatts & BT_STATUS_OFFSET_MASK) == 0);
|
|
Assert(!heaptid || nkeyatts > 0);
|
|
Assert(!BTreeTupleIsPivot(itup) || nkeyatts == 0);
|
|
|
|
itup->t_info |= INDEX_ALT_TID_MASK;
|
|
|
|
if (heaptid)
|
|
nkeyatts |= BT_PIVOT_HEAP_TID_ATTR;
|
|
|
|
/* BT_IS_POSTING bit is deliberately unset here */
|
|
ItemPointerSetOffsetNumber(&itup->t_tid, nkeyatts);
|
|
Assert(BTreeTupleIsPivot(itup));
|
|
}
|
|
|
|
/*
|
|
* Get/set leaf page's "top parent" link from its high key. Used during page
|
|
* deletion.
|
|
*
|
|
* Note: Cannot assert that tuple is a pivot tuple. If we did so then
|
|
* !heapkeyspace indexes would exhibit false positive assertion failures.
|
|
*/
|
|
static inline BlockNumber
|
|
BTreeTupleGetTopParent(IndexTuple leafhikey)
|
|
{
|
|
return ItemPointerGetBlockNumberNoCheck(&leafhikey->t_tid);
|
|
}
|
|
|
|
static inline void
|
|
BTreeTupleSetTopParent(IndexTuple leafhikey, BlockNumber blkno)
|
|
{
|
|
ItemPointerSetBlockNumber(&leafhikey->t_tid, blkno);
|
|
BTreeTupleSetNAtts(leafhikey, 0, false);
|
|
}
|
|
|
|
/*
|
|
* Get tiebreaker heap TID attribute, if any.
|
|
*
|
|
* This returns the first/lowest heap TID in the case of a posting list tuple.
|
|
*/
|
|
static inline ItemPointer
|
|
BTreeTupleGetHeapTID(IndexTuple itup)
|
|
{
|
|
if (BTreeTupleIsPivot(itup))
|
|
{
|
|
/* Pivot tuple heap TID representation? */
|
|
if ((ItemPointerGetOffsetNumberNoCheck(&itup->t_tid) &
|
|
BT_PIVOT_HEAP_TID_ATTR) != 0)
|
|
return (ItemPointer) ((char *) itup + IndexTupleSize(itup) -
|
|
sizeof(ItemPointerData));
|
|
|
|
/* Heap TID attribute was truncated */
|
|
return NULL;
|
|
}
|
|
else if (BTreeTupleIsPosting(itup))
|
|
return BTreeTupleGetPosting(itup);
|
|
|
|
return &itup->t_tid;
|
|
}
|
|
|
|
/*
|
|
* Get maximum heap TID attribute, which could be the only TID in the case of
|
|
* a non-pivot tuple that does not have a posting list tuple.
|
|
*
|
|
* Works with non-pivot tuples only.
|
|
*/
|
|
static inline ItemPointer
|
|
BTreeTupleGetMaxHeapTID(IndexTuple itup)
|
|
{
|
|
Assert(!BTreeTupleIsPivot(itup));
|
|
|
|
if (BTreeTupleIsPosting(itup))
|
|
{
|
|
uint16 nposting = BTreeTupleGetNPosting(itup);
|
|
|
|
return BTreeTupleGetPostingN(itup, nposting - 1);
|
|
}
|
|
|
|
return &itup->t_tid;
|
|
}
|
|
|
|
/*
|
|
* Operator strategy numbers for B-tree have been moved to access/stratnum.h,
|
|
* because many places need to use them in ScanKeyInit() calls.
|
|
*
|
|
* The strategy numbers are chosen so that we can commute them by
|
|
* subtraction, thus:
|
|
*/
|
|
#define BTCommuteStrategyNumber(strat) (BTMaxStrategyNumber + 1 - (strat))
|
|
|
|
/*
|
|
* When a new operator class is declared, we require that the user
|
|
* supply us with an amproc procedure (BTORDER_PROC) for determining
|
|
* whether, for two keys a and b, a < b, a = b, or a > b. This routine
|
|
* must return < 0, 0, > 0, respectively, in these three cases.
|
|
*
|
|
* To facilitate accelerated sorting, an operator class may choose to
|
|
* offer a second procedure (BTSORTSUPPORT_PROC). For full details, see
|
|
* src/include/utils/sortsupport.h.
|
|
*
|
|
* To support window frames defined by "RANGE offset PRECEDING/FOLLOWING",
|
|
* an operator class may choose to offer a third amproc procedure
|
|
* (BTINRANGE_PROC), independently of whether it offers sortsupport.
|
|
* For full details, see doc/src/sgml/btree.sgml.
|
|
*
|
|
* To facilitate B-Tree deduplication, an operator class may choose to
|
|
* offer a forth amproc procedure (BTEQUALIMAGE_PROC). For full details,
|
|
* see doc/src/sgml/btree.sgml.
|
|
*/
|
|
|
|
#define BTORDER_PROC 1
|
|
#define BTSORTSUPPORT_PROC 2
|
|
#define BTINRANGE_PROC 3
|
|
#define BTEQUALIMAGE_PROC 4
|
|
#define BTOPTIONS_PROC 5
|
|
#define BTNProcs 5
|
|
|
|
/*
|
|
* We need to be able to tell the difference between read and write
|
|
* requests for pages, in order to do locking correctly.
|
|
*/
|
|
|
|
#define BT_READ BUFFER_LOCK_SHARE
|
|
#define BT_WRITE BUFFER_LOCK_EXCLUSIVE
|
|
|
|
/*
|
|
* BTStackData -- As we descend a tree, we push the location of pivot
|
|
* tuples whose downlink we are about to follow onto a private stack. If
|
|
* we split a leaf, we use this stack to walk back up the tree and insert
|
|
* data into its parent page at the correct location. We also have to
|
|
* recursively insert into the grandparent page if and when the parent page
|
|
* splits. Our private stack can become stale due to concurrent page
|
|
* splits and page deletions, but it should never give us an irredeemably
|
|
* bad picture.
|
|
*/
|
|
typedef struct BTStackData
|
|
{
|
|
BlockNumber bts_blkno;
|
|
OffsetNumber bts_offset;
|
|
struct BTStackData *bts_parent;
|
|
} BTStackData;
|
|
|
|
typedef BTStackData *BTStack;
|
|
|
|
/*
|
|
* BTScanInsertData is the btree-private state needed to find an initial
|
|
* position for an indexscan, or to insert new tuples -- an "insertion
|
|
* scankey" (not to be confused with a search scankey). It's used to descend
|
|
* a B-Tree using _bt_search.
|
|
*
|
|
* heapkeyspace indicates if we expect all keys in the index to be physically
|
|
* unique because heap TID is used as a tiebreaker attribute, and if index may
|
|
* have truncated key attributes in pivot tuples. This is actually a property
|
|
* of the index relation itself (not an indexscan). heapkeyspace indexes are
|
|
* indexes whose version is >= version 4. It's convenient to keep this close
|
|
* by, rather than accessing the metapage repeatedly.
|
|
*
|
|
* allequalimage is set to indicate that deduplication is safe for the index.
|
|
* This is also a property of the index relation rather than an indexscan.
|
|
*
|
|
* anynullkeys indicates if any of the keys had NULL value when scankey was
|
|
* built from index tuple (note that already-truncated tuple key attributes
|
|
* set NULL as a placeholder key value, which also affects value of
|
|
* anynullkeys). This is a convenience for unique index non-pivot tuple
|
|
* insertion, which usually temporarily unsets scantid, but shouldn't iff
|
|
* anynullkeys is true. Value generally matches non-pivot tuple's HasNulls
|
|
* bit, but may not when inserting into an INCLUDE index (tuple header value
|
|
* is affected by the NULL-ness of both key and non-key attributes).
|
|
*
|
|
* When nextkey is false (the usual case), _bt_search and _bt_binsrch will
|
|
* locate the first item >= scankey. When nextkey is true, they will locate
|
|
* the first item > scan key.
|
|
*
|
|
* pivotsearch is set to true by callers that want to re-find a leaf page
|
|
* using a scankey built from a leaf page's high key. Most callers set this
|
|
* to false.
|
|
*
|
|
* scantid is the heap TID that is used as a final tiebreaker attribute. It
|
|
* is set to NULL when index scan doesn't need to find a position for a
|
|
* specific physical tuple. Must be set when inserting new tuples into
|
|
* heapkeyspace indexes, since every tuple in the tree unambiguously belongs
|
|
* in one exact position (it's never set with !heapkeyspace indexes, though).
|
|
* Despite the representational difference, nbtree search code considers
|
|
* scantid to be just another insertion scankey attribute.
|
|
*
|
|
* scankeys is an array of scan key entries for attributes that are compared
|
|
* before scantid (user-visible attributes). keysz is the size of the array.
|
|
* During insertion, there must be a scan key for every attribute, but when
|
|
* starting a regular index scan some can be omitted. The array is used as a
|
|
* flexible array member, though it's sized in a way that makes it possible to
|
|
* use stack allocations. See nbtree/README for full details.
|
|
*/
|
|
typedef struct BTScanInsertData
|
|
{
|
|
bool heapkeyspace;
|
|
bool allequalimage;
|
|
bool anynullkeys;
|
|
bool nextkey;
|
|
bool pivotsearch;
|
|
ItemPointer scantid; /* tiebreaker for scankeys */
|
|
int keysz; /* Size of scankeys array */
|
|
ScanKeyData scankeys[INDEX_MAX_KEYS]; /* Must appear last */
|
|
} BTScanInsertData;
|
|
|
|
typedef BTScanInsertData *BTScanInsert;
|
|
|
|
/*
|
|
* BTInsertStateData is a working area used during insertion.
|
|
*
|
|
* This is filled in after descending the tree to the first leaf page the new
|
|
* tuple might belong on. Tracks the current position while performing
|
|
* uniqueness check, before we have determined which exact page to insert
|
|
* to.
|
|
*
|
|
* (This should be private to nbtinsert.c, but it's also used by
|
|
* _bt_binsrch_insert)
|
|
*/
|
|
typedef struct BTInsertStateData
|
|
{
|
|
IndexTuple itup; /* Item we're inserting */
|
|
Size itemsz; /* Size of itup -- should be MAXALIGN()'d */
|
|
BTScanInsert itup_key; /* Insertion scankey */
|
|
|
|
/* Buffer containing leaf page we're likely to insert itup on */
|
|
Buffer buf;
|
|
|
|
/*
|
|
* Cache of bounds within the current buffer. Only used for insertions
|
|
* where _bt_check_unique is called. See _bt_binsrch_insert and
|
|
* _bt_findinsertloc for details.
|
|
*/
|
|
bool bounds_valid;
|
|
OffsetNumber low;
|
|
OffsetNumber stricthigh;
|
|
|
|
/*
|
|
* if _bt_binsrch_insert found the location inside existing posting list,
|
|
* save the position inside the list. -1 sentinel value indicates overlap
|
|
* with an existing posting list tuple that has its LP_DEAD bit set.
|
|
*/
|
|
int postingoff;
|
|
} BTInsertStateData;
|
|
|
|
typedef BTInsertStateData *BTInsertState;
|
|
|
|
/*
|
|
* State used to representing an individual pending tuple during
|
|
* deduplication.
|
|
*/
|
|
typedef struct BTDedupInterval
|
|
{
|
|
OffsetNumber baseoff;
|
|
uint16 nitems;
|
|
} BTDedupInterval;
|
|
|
|
/*
|
|
* BTDedupStateData is a working area used during deduplication.
|
|
*
|
|
* The status info fields track the state of a whole-page deduplication pass.
|
|
* State about the current pending posting list is also tracked.
|
|
*
|
|
* A pending posting list is comprised of a contiguous group of equal items
|
|
* from the page, starting from page offset number 'baseoff'. This is the
|
|
* offset number of the "base" tuple for new posting list. 'nitems' is the
|
|
* current total number of existing items from the page that will be merged to
|
|
* make a new posting list tuple, including the base tuple item. (Existing
|
|
* items may themselves be posting list tuples, or regular non-pivot tuples.)
|
|
*
|
|
* The total size of the existing tuples to be freed when pending posting list
|
|
* is processed gets tracked by 'phystupsize'. This information allows
|
|
* deduplication to calculate the space saving for each new posting list
|
|
* tuple, and for the entire pass over the page as a whole.
|
|
*/
|
|
typedef struct BTDedupStateData
|
|
{
|
|
/* Deduplication status info for entire pass over page */
|
|
bool deduplicate; /* Still deduplicating page? */
|
|
int nmaxitems; /* Number of max-sized tuples so far */
|
|
Size maxpostingsize; /* Limit on size of final tuple */
|
|
|
|
/* Metadata about base tuple of current pending posting list */
|
|
IndexTuple base; /* Use to form new posting list */
|
|
OffsetNumber baseoff; /* page offset of base */
|
|
Size basetupsize; /* base size without original posting list */
|
|
|
|
/* Other metadata about pending posting list */
|
|
ItemPointer htids; /* Heap TIDs in pending posting list */
|
|
int nhtids; /* Number of heap TIDs in htids array */
|
|
int nitems; /* Number of existing tuples/line pointers */
|
|
Size phystupsize; /* Includes line pointer overhead */
|
|
|
|
/*
|
|
* Array of tuples to go on new version of the page. Contains one entry
|
|
* for each group of consecutive items. Note that existing tuples that
|
|
* will not become posting list tuples do not appear in the array (they
|
|
* are implicitly unchanged by deduplication pass).
|
|
*/
|
|
int nintervals; /* current number of intervals in array */
|
|
BTDedupInterval intervals[MaxIndexTuplesPerPage];
|
|
} BTDedupStateData;
|
|
|
|
typedef BTDedupStateData *BTDedupState;
|
|
|
|
/*
|
|
* BTVacuumPostingData is state that represents how to VACUUM (or delete) a
|
|
* posting list tuple when some (though not all) of its TIDs are to be
|
|
* deleted.
|
|
*
|
|
* Convention is that itup field is the original posting list tuple on input,
|
|
* and palloc()'d final tuple used to overwrite existing tuple on output.
|
|
*/
|
|
typedef struct BTVacuumPostingData
|
|
{
|
|
/* Tuple that will be/was updated */
|
|
IndexTuple itup;
|
|
OffsetNumber updatedoffset;
|
|
|
|
/* State needed to describe final itup in WAL */
|
|
uint16 ndeletedtids;
|
|
uint16 deletetids[FLEXIBLE_ARRAY_MEMBER];
|
|
} BTVacuumPostingData;
|
|
|
|
typedef BTVacuumPostingData *BTVacuumPosting;
|
|
|
|
/*
|
|
* BTScanOpaqueData is the btree-private state needed for an indexscan.
|
|
* This consists of preprocessed scan keys (see _bt_preprocess_keys() for
|
|
* details of the preprocessing), information about the current location
|
|
* of the scan, and information about the marked location, if any. (We use
|
|
* BTScanPosData to represent the data needed for each of current and marked
|
|
* locations.) In addition we can remember some known-killed index entries
|
|
* that must be marked before we can move off the current page.
|
|
*
|
|
* Index scans work a page at a time: we pin and read-lock the page, identify
|
|
* all the matching items on the page and save them in BTScanPosData, then
|
|
* release the read-lock while returning the items to the caller for
|
|
* processing. This approach minimizes lock/unlock traffic. Note that we
|
|
* keep the pin on the index page until the caller is done with all the items
|
|
* (this is needed for VACUUM synchronization, see nbtree/README). When we
|
|
* are ready to step to the next page, if the caller has told us any of the
|
|
* items were killed, we re-lock the page to mark them killed, then unlock.
|
|
* Finally we drop the pin and step to the next page in the appropriate
|
|
* direction.
|
|
*
|
|
* If we are doing an index-only scan, we save the entire IndexTuple for each
|
|
* matched item, otherwise only its heap TID and offset. The IndexTuples go
|
|
* into a separate workspace array; each BTScanPosItem stores its tuple's
|
|
* offset within that array. Posting list tuples store a "base" tuple once,
|
|
* allowing the same key to be returned for each TID in the posting list
|
|
* tuple.
|
|
*/
|
|
|
|
typedef struct BTScanPosItem /* what we remember about each match */
|
|
{
|
|
ItemPointerData heapTid; /* TID of referenced heap item */
|
|
OffsetNumber indexOffset; /* index item's location within page */
|
|
LocationIndex tupleOffset; /* IndexTuple's offset in workspace, if any */
|
|
} BTScanPosItem;
|
|
|
|
typedef struct BTScanPosData
|
|
{
|
|
Buffer buf; /* if valid, the buffer is pinned */
|
|
|
|
XLogRecPtr lsn; /* pos in the WAL stream when page was read */
|
|
BlockNumber currPage; /* page referenced by items array */
|
|
BlockNumber nextPage; /* page's right link when we scanned it */
|
|
|
|
/*
|
|
* moreLeft and moreRight track whether we think there may be matching
|
|
* index entries to the left and right of the current page, respectively.
|
|
* We can clear the appropriate one of these flags when _bt_checkkeys()
|
|
* returns continuescan = false.
|
|
*/
|
|
bool moreLeft;
|
|
bool moreRight;
|
|
|
|
/*
|
|
* If we are doing an index-only scan, nextTupleOffset is the first free
|
|
* location in the associated tuple storage workspace.
|
|
*/
|
|
int nextTupleOffset;
|
|
|
|
/*
|
|
* The items array is always ordered in index order (ie, increasing
|
|
* indexoffset). When scanning backwards it is convenient to fill the
|
|
* array back-to-front, so we start at the last slot and fill downwards.
|
|
* Hence we need both a first-valid-entry and a last-valid-entry counter.
|
|
* itemIndex is a cursor showing which entry was last returned to caller.
|
|
*/
|
|
int firstItem; /* first valid index in items[] */
|
|
int lastItem; /* last valid index in items[] */
|
|
int itemIndex; /* current index in items[] */
|
|
|
|
BTScanPosItem items[MaxTIDsPerBTreePage]; /* MUST BE LAST */
|
|
} BTScanPosData;
|
|
|
|
typedef BTScanPosData *BTScanPos;
|
|
|
|
#define BTScanPosIsPinned(scanpos) \
|
|
( \
|
|
AssertMacro(BlockNumberIsValid((scanpos).currPage) || \
|
|
!BufferIsValid((scanpos).buf)), \
|
|
BufferIsValid((scanpos).buf) \
|
|
)
|
|
#define BTScanPosUnpin(scanpos) \
|
|
do { \
|
|
ReleaseBuffer((scanpos).buf); \
|
|
(scanpos).buf = InvalidBuffer; \
|
|
} while (0)
|
|
#define BTScanPosUnpinIfPinned(scanpos) \
|
|
do { \
|
|
if (BTScanPosIsPinned(scanpos)) \
|
|
BTScanPosUnpin(scanpos); \
|
|
} while (0)
|
|
|
|
#define BTScanPosIsValid(scanpos) \
|
|
( \
|
|
AssertMacro(BlockNumberIsValid((scanpos).currPage) || \
|
|
!BufferIsValid((scanpos).buf)), \
|
|
BlockNumberIsValid((scanpos).currPage) \
|
|
)
|
|
#define BTScanPosInvalidate(scanpos) \
|
|
do { \
|
|
(scanpos).currPage = InvalidBlockNumber; \
|
|
(scanpos).nextPage = InvalidBlockNumber; \
|
|
(scanpos).buf = InvalidBuffer; \
|
|
(scanpos).lsn = InvalidXLogRecPtr; \
|
|
(scanpos).nextTupleOffset = 0; \
|
|
} while (0)
|
|
|
|
/* We need one of these for each equality-type SK_SEARCHARRAY scan key */
|
|
typedef struct BTArrayKeyInfo
|
|
{
|
|
int scan_key; /* index of associated key in arrayKeyData */
|
|
int cur_elem; /* index of current element in elem_values */
|
|
int mark_elem; /* index of marked element in elem_values */
|
|
int num_elems; /* number of elems in current array value */
|
|
Datum *elem_values; /* array of num_elems Datums */
|
|
} BTArrayKeyInfo;
|
|
|
|
typedef struct BTScanOpaqueData
|
|
{
|
|
/* these fields are set by _bt_preprocess_keys(): */
|
|
bool qual_ok; /* false if qual can never be satisfied */
|
|
int numberOfKeys; /* number of preprocessed scan keys */
|
|
ScanKey keyData; /* array of preprocessed scan keys */
|
|
|
|
/* workspace for SK_SEARCHARRAY support */
|
|
ScanKey arrayKeyData; /* modified copy of scan->keyData */
|
|
int numArrayKeys; /* number of equality-type array keys (-1 if
|
|
* there are any unsatisfiable array keys) */
|
|
int arrayKeyCount; /* count indicating number of array scan keys
|
|
* processed */
|
|
BTArrayKeyInfo *arrayKeys; /* info about each equality-type array key */
|
|
MemoryContext arrayContext; /* scan-lifespan context for array data */
|
|
|
|
/* info about killed items if any (killedItems is NULL if never used) */
|
|
int *killedItems; /* currPos.items indexes of killed items */
|
|
int numKilled; /* number of currently stored items */
|
|
|
|
/*
|
|
* If we are doing an index-only scan, these are the tuple storage
|
|
* workspaces for the currPos and markPos respectively. Each is of size
|
|
* BLCKSZ, so it can hold as much as a full page's worth of tuples.
|
|
*/
|
|
char *currTuples; /* tuple storage for currPos */
|
|
char *markTuples; /* tuple storage for markPos */
|
|
|
|
/*
|
|
* If the marked position is on the same page as current position, we
|
|
* don't use markPos, but just keep the marked itemIndex in markItemIndex
|
|
* (all the rest of currPos is valid for the mark position). Hence, to
|
|
* determine if there is a mark, first look at markItemIndex, then at
|
|
* markPos.
|
|
*/
|
|
int markItemIndex; /* itemIndex, or -1 if not valid */
|
|
|
|
/* keep these last in struct for efficiency */
|
|
BTScanPosData currPos; /* current position data */
|
|
BTScanPosData markPos; /* marked position, if any */
|
|
} BTScanOpaqueData;
|
|
|
|
typedef BTScanOpaqueData *BTScanOpaque;
|
|
|
|
/*
|
|
* We use some private sk_flags bits in preprocessed scan keys. We're allowed
|
|
* to use bits 16-31 (see skey.h). The uppermost bits are copied from the
|
|
* index's indoption[] array entry for the index attribute.
|
|
*/
|
|
#define SK_BT_REQFWD 0x00010000 /* required to continue forward scan */
|
|
#define SK_BT_REQBKWD 0x00020000 /* required to continue backward scan */
|
|
#define SK_BT_INDOPTION_SHIFT 24 /* must clear the above bits */
|
|
#define SK_BT_DESC (INDOPTION_DESC << SK_BT_INDOPTION_SHIFT)
|
|
#define SK_BT_NULLS_FIRST (INDOPTION_NULLS_FIRST << SK_BT_INDOPTION_SHIFT)
|
|
|
|
typedef struct BTOptions
|
|
{
|
|
int32 varlena_header_; /* varlena header (do not touch directly!) */
|
|
int fillfactor; /* page fill factor in percent (0..100) */
|
|
float8 vacuum_cleanup_index_scale_factor; /* deprecated */
|
|
bool deduplicate_items; /* Try to deduplicate items? */
|
|
} BTOptions;
|
|
|
|
#define BTGetFillFactor(relation) \
|
|
(AssertMacro(relation->rd_rel->relkind == RELKIND_INDEX && \
|
|
relation->rd_rel->relam == BTREE_AM_OID), \
|
|
(relation)->rd_options ? \
|
|
((BTOptions *) (relation)->rd_options)->fillfactor : \
|
|
BTREE_DEFAULT_FILLFACTOR)
|
|
#define BTGetTargetPageFreeSpace(relation) \
|
|
(BLCKSZ * (100 - BTGetFillFactor(relation)) / 100)
|
|
#define BTGetDeduplicateItems(relation) \
|
|
(AssertMacro(relation->rd_rel->relkind == RELKIND_INDEX && \
|
|
relation->rd_rel->relam == BTREE_AM_OID), \
|
|
((relation)->rd_options ? \
|
|
((BTOptions *) (relation)->rd_options)->deduplicate_items : true))
|
|
|
|
/*
|
|
* Constant definition for progress reporting. Phase numbers must match
|
|
* btbuildphasename.
|
|
*/
|
|
/* PROGRESS_CREATEIDX_SUBPHASE_INITIALIZE is 1 (see progress.h) */
|
|
#define PROGRESS_BTREE_PHASE_INDEXBUILD_TABLESCAN 2
|
|
#define PROGRESS_BTREE_PHASE_PERFORMSORT_1 3
|
|
#define PROGRESS_BTREE_PHASE_PERFORMSORT_2 4
|
|
#define PROGRESS_BTREE_PHASE_LEAF_LOAD 5
|
|
|
|
/*
|
|
* external entry points for btree, in nbtree.c
|
|
*/
|
|
extern void btbuildempty(Relation index);
|
|
extern bool btinsert(Relation rel, Datum *values, bool *isnull,
|
|
ItemPointer ht_ctid, Relation heapRel,
|
|
IndexUniqueCheck checkUnique,
|
|
bool indexUnchanged,
|
|
struct IndexInfo *indexInfo);
|
|
extern IndexScanDesc btbeginscan(Relation rel, int nkeys, int norderbys);
|
|
extern Size btestimateparallelscan(void);
|
|
extern void btinitparallelscan(void *target);
|
|
extern bool btgettuple(IndexScanDesc scan, ScanDirection dir);
|
|
extern int64 btgetbitmap(IndexScanDesc scan, TIDBitmap *tbm);
|
|
extern void btrescan(IndexScanDesc scan, ScanKey scankey, int nscankeys,
|
|
ScanKey orderbys, int norderbys);
|
|
extern void btparallelrescan(IndexScanDesc scan);
|
|
extern void btendscan(IndexScanDesc scan);
|
|
extern void btmarkpos(IndexScanDesc scan);
|
|
extern void btrestrpos(IndexScanDesc scan);
|
|
extern IndexBulkDeleteResult *btbulkdelete(IndexVacuumInfo *info,
|
|
IndexBulkDeleteResult *stats,
|
|
IndexBulkDeleteCallback callback,
|
|
void *callback_state);
|
|
extern IndexBulkDeleteResult *btvacuumcleanup(IndexVacuumInfo *info,
|
|
IndexBulkDeleteResult *stats);
|
|
extern bool btcanreturn(Relation index, int attno);
|
|
|
|
/*
|
|
* prototypes for internal functions in nbtree.c
|
|
*/
|
|
extern bool _bt_parallel_seize(IndexScanDesc scan, BlockNumber *pageno);
|
|
extern void _bt_parallel_release(IndexScanDesc scan, BlockNumber scan_page);
|
|
extern void _bt_parallel_done(IndexScanDesc scan);
|
|
extern void _bt_parallel_advance_array_keys(IndexScanDesc scan);
|
|
|
|
/*
|
|
* prototypes for functions in nbtdedup.c
|
|
*/
|
|
extern void _bt_dedup_pass(Relation rel, Buffer buf, Relation heapRel,
|
|
IndexTuple newitem, Size newitemsz,
|
|
bool bottomupdedup);
|
|
extern bool _bt_bottomupdel_pass(Relation rel, Buffer buf, Relation heapRel,
|
|
Size newitemsz);
|
|
extern void _bt_dedup_start_pending(BTDedupState state, IndexTuple base,
|
|
OffsetNumber baseoff);
|
|
extern bool _bt_dedup_save_htid(BTDedupState state, IndexTuple itup);
|
|
extern Size _bt_dedup_finish_pending(Page newpage, BTDedupState state);
|
|
extern IndexTuple _bt_form_posting(IndexTuple base, ItemPointer htids,
|
|
int nhtids);
|
|
extern void _bt_update_posting(BTVacuumPosting vacposting);
|
|
extern IndexTuple _bt_swap_posting(IndexTuple newitem, IndexTuple oposting,
|
|
int postingoff);
|
|
|
|
/*
|
|
* prototypes for functions in nbtinsert.c
|
|
*/
|
|
extern bool _bt_doinsert(Relation rel, IndexTuple itup,
|
|
IndexUniqueCheck checkUnique, bool indexUnchanged,
|
|
Relation heapRel);
|
|
extern void _bt_finish_split(Relation rel, Buffer lbuf, BTStack stack);
|
|
extern Buffer _bt_getstackbuf(Relation rel, BTStack stack, BlockNumber child);
|
|
|
|
/*
|
|
* prototypes for functions in nbtsplitloc.c
|
|
*/
|
|
extern OffsetNumber _bt_findsplitloc(Relation rel, Page origpage,
|
|
OffsetNumber newitemoff, Size newitemsz, IndexTuple newitem,
|
|
bool *newitemonleft);
|
|
|
|
/*
|
|
* prototypes for functions in nbtpage.c
|
|
*/
|
|
extern void _bt_initmetapage(Page page, BlockNumber rootbknum, uint32 level,
|
|
bool allequalimage);
|
|
extern bool _bt_vacuum_needs_cleanup(Relation rel);
|
|
extern void _bt_set_cleanup_info(Relation rel, BlockNumber num_delpages);
|
|
extern void _bt_upgrademetapage(Page page);
|
|
extern Buffer _bt_getroot(Relation rel, int access);
|
|
extern Buffer _bt_gettrueroot(Relation rel);
|
|
extern int _bt_getrootheight(Relation rel);
|
|
extern void _bt_metaversion(Relation rel, bool *heapkeyspace,
|
|
bool *allequalimage);
|
|
extern void _bt_checkpage(Relation rel, Buffer buf);
|
|
extern Buffer _bt_getbuf(Relation rel, BlockNumber blkno, int access);
|
|
extern Buffer _bt_relandgetbuf(Relation rel, Buffer obuf,
|
|
BlockNumber blkno, int access);
|
|
extern void _bt_relbuf(Relation rel, Buffer buf);
|
|
extern void _bt_lockbuf(Relation rel, Buffer buf, int access);
|
|
extern void _bt_unlockbuf(Relation rel, Buffer buf);
|
|
extern bool _bt_conditionallockbuf(Relation rel, Buffer buf);
|
|
extern void _bt_upgradelockbufcleanup(Relation rel, Buffer buf);
|
|
extern void _bt_pageinit(Page page, Size size);
|
|
extern void _bt_delitems_vacuum(Relation rel, Buffer buf,
|
|
OffsetNumber *deletable, int ndeletable,
|
|
BTVacuumPosting *updatable, int nupdatable);
|
|
extern void _bt_delitems_delete_check(Relation rel, Buffer buf,
|
|
Relation heapRel,
|
|
TM_IndexDeleteOp *delstate);
|
|
extern void _bt_pagedel(Relation rel, Buffer leafbuf, BTVacState *vstate);
|
|
extern void _bt_pendingfsm_init(Relation rel, BTVacState *vstate,
|
|
bool cleanuponly);
|
|
extern void _bt_pendingfsm_finalize(Relation rel, BTVacState *vstate);
|
|
|
|
/*
|
|
* prototypes for functions in nbtsearch.c
|
|
*/
|
|
extern BTStack _bt_search(Relation rel, BTScanInsert key, Buffer *bufP,
|
|
int access, Snapshot snapshot);
|
|
extern Buffer _bt_moveright(Relation rel, BTScanInsert key, Buffer buf,
|
|
bool forupdate, BTStack stack, int access, Snapshot snapshot);
|
|
extern OffsetNumber _bt_binsrch_insert(Relation rel, BTInsertState insertstate);
|
|
extern int32 _bt_compare(Relation rel, BTScanInsert key, Page page, OffsetNumber offnum);
|
|
extern bool _bt_first(IndexScanDesc scan, ScanDirection dir);
|
|
extern bool _bt_next(IndexScanDesc scan, ScanDirection dir);
|
|
extern Buffer _bt_get_endpoint(Relation rel, uint32 level, bool rightmost,
|
|
Snapshot snapshot);
|
|
|
|
/*
|
|
* prototypes for functions in nbtutils.c
|
|
*/
|
|
extern BTScanInsert _bt_mkscankey(Relation rel, IndexTuple itup);
|
|
extern void _bt_freestack(BTStack stack);
|
|
extern void _bt_preprocess_array_keys(IndexScanDesc scan);
|
|
extern void _bt_start_array_keys(IndexScanDesc scan, ScanDirection dir);
|
|
extern bool _bt_advance_array_keys(IndexScanDesc scan, ScanDirection dir);
|
|
extern void _bt_mark_array_keys(IndexScanDesc scan);
|
|
extern void _bt_restore_array_keys(IndexScanDesc scan);
|
|
extern void _bt_preprocess_keys(IndexScanDesc scan);
|
|
extern bool _bt_checkkeys(IndexScanDesc scan, IndexTuple tuple,
|
|
int tupnatts, ScanDirection dir, bool *continuescan);
|
|
extern void _bt_killitems(IndexScanDesc scan);
|
|
extern BTCycleId _bt_vacuum_cycleid(Relation rel);
|
|
extern BTCycleId _bt_start_vacuum(Relation rel);
|
|
extern void _bt_end_vacuum(Relation rel);
|
|
extern void _bt_end_vacuum_callback(int code, Datum arg);
|
|
extern Size BTreeShmemSize(void);
|
|
extern void BTreeShmemInit(void);
|
|
extern bytea *btoptions(Datum reloptions, bool validate);
|
|
extern bool btproperty(Oid index_oid, int attno,
|
|
IndexAMProperty prop, const char *propname,
|
|
bool *res, bool *isnull);
|
|
extern char *btbuildphasename(int64 phasenum);
|
|
extern IndexTuple _bt_truncate(Relation rel, IndexTuple lastleft,
|
|
IndexTuple firstright, BTScanInsert itup_key);
|
|
extern int _bt_keep_natts_fast(Relation rel, IndexTuple lastleft,
|
|
IndexTuple firstright);
|
|
extern bool _bt_check_natts(Relation rel, bool heapkeyspace, Page page,
|
|
OffsetNumber offnum);
|
|
extern void _bt_check_third_page(Relation rel, Relation heap,
|
|
bool needheaptidspace, Page page, IndexTuple newtup);
|
|
extern bool _bt_allequalimage(Relation rel, bool debugmessage);
|
|
|
|
/*
|
|
* prototypes for functions in nbtvalidate.c
|
|
*/
|
|
extern bool btvalidate(Oid opclassoid);
|
|
extern void btadjustmembers(Oid opfamilyoid,
|
|
Oid opclassoid,
|
|
List *operators,
|
|
List *functions);
|
|
|
|
/*
|
|
* prototypes for functions in nbtsort.c
|
|
*/
|
|
extern IndexBuildResult *btbuild(Relation heap, Relation index,
|
|
struct IndexInfo *indexInfo);
|
|
extern void _bt_parallel_build_main(dsm_segment *seg, shm_toc *toc);
|
|
|
|
#endif /* NBTREE_H */
|