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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-04 12:19:15 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-04 12:19:15 +0000 |
commit | 6eb9c5a5657d1fe77b55cc261450f3538d35a94d (patch) | |
tree | 657d8194422a5daccecfd42d654b8a245ef7b4c8 /src/include/access/brin_tuple.h | |
parent | Initial commit. (diff) | |
download | postgresql-13-6eb9c5a5657d1fe77b55cc261450f3538d35a94d.tar.xz postgresql-13-6eb9c5a5657d1fe77b55cc261450f3538d35a94d.zip |
Adding upstream version 13.4.upstream/13.4upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/include/access/brin_tuple.h')
-rw-r--r-- | src/include/access/brin_tuple.h | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/src/include/access/brin_tuple.h b/src/include/access/brin_tuple.h new file mode 100644 index 0000000..a9ccc39 --- /dev/null +++ b/src/include/access/brin_tuple.h @@ -0,0 +1,102 @@ +/* + * brin_tuple.h + * Declarations for dealing with BRIN-specific tuples. + * + * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group + * Portions Copyright (c) 1994, Regents of the University of California + * + * IDENTIFICATION + * src/include/access/brin_tuple.h + */ +#ifndef BRIN_TUPLE_H +#define BRIN_TUPLE_H + +#include "access/brin_internal.h" +#include "access/tupdesc.h" + + +/* + * A BRIN index stores one index tuple per page range. Each index tuple + * has one BrinValues struct for each indexed column; in turn, each BrinValues + * has (besides the null flags) an array of Datum whose size is determined by + * the opclass. + */ +typedef struct BrinValues +{ + AttrNumber bv_attno; /* index attribute number */ + bool bv_hasnulls; /* are there any nulls in the page range? */ + bool bv_allnulls; /* are all values nulls in the page range? */ + Datum *bv_values; /* current accumulated values */ +} BrinValues; + +/* + * This struct is used to represent an in-memory index tuple. The values can + * only be meaningfully decoded with an appropriate BrinDesc. + */ +typedef struct BrinMemTuple +{ + bool bt_placeholder; /* this is a placeholder tuple */ + BlockNumber bt_blkno; /* heap blkno that the tuple is for */ + MemoryContext bt_context; /* memcxt holding the bt_columns values */ + /* output arrays for brin_deform_tuple: */ + Datum *bt_values; /* values array */ + bool *bt_allnulls; /* allnulls array */ + bool *bt_hasnulls; /* hasnulls array */ + /* not an output array, but must be last */ + BrinValues bt_columns[FLEXIBLE_ARRAY_MEMBER]; +} BrinMemTuple; + +/* + * An on-disk BRIN tuple. This is possibly followed by a nulls bitmask, with + * room for 2 null bits (two bits for each indexed column); an opclass-defined + * number of Datum values for each column follow. + */ +typedef struct BrinTuple +{ + /* heap block number that the tuple is for */ + BlockNumber bt_blkno; + + /* --------------- + * bt_info is laid out in the following fashion: + * + * 7th (high) bit: has nulls + * 6th bit: is placeholder tuple + * 5th bit: unused + * 4-0 bit: offset of data + * --------------- + */ + uint8 bt_info; +} BrinTuple; + +#define SizeOfBrinTuple (offsetof(BrinTuple, bt_info) + sizeof(uint8)) + +/* + * bt_info manipulation macros + */ +#define BRIN_OFFSET_MASK 0x1F +/* bit 0x20 is not used at present */ +#define BRIN_PLACEHOLDER_MASK 0x40 +#define BRIN_NULLS_MASK 0x80 + +#define BrinTupleDataOffset(tup) ((Size) (((BrinTuple *) (tup))->bt_info & BRIN_OFFSET_MASK)) +#define BrinTupleHasNulls(tup) (((((BrinTuple *) (tup))->bt_info & BRIN_NULLS_MASK)) != 0) +#define BrinTupleIsPlaceholder(tup) (((((BrinTuple *) (tup))->bt_info & BRIN_PLACEHOLDER_MASK)) != 0) + + +extern BrinTuple *brin_form_tuple(BrinDesc *brdesc, BlockNumber blkno, + BrinMemTuple *tuple, Size *size); +extern BrinTuple *brin_form_placeholder_tuple(BrinDesc *brdesc, + BlockNumber blkno, Size *size); +extern void brin_free_tuple(BrinTuple *tuple); +extern BrinTuple *brin_copy_tuple(BrinTuple *tuple, Size len, + BrinTuple *dest, Size *destsz); +extern bool brin_tuples_equal(const BrinTuple *a, Size alen, + const BrinTuple *b, Size blen); + +extern BrinMemTuple *brin_new_memtuple(BrinDesc *brdesc); +extern BrinMemTuple *brin_memtuple_initialize(BrinMemTuple *dtuple, + BrinDesc *brdesc); +extern BrinMemTuple *brin_deform_tuple(BrinDesc *brdesc, + BrinTuple *tuple, BrinMemTuple *dMemtuple); + +#endif /* BRIN_TUPLE_H */ |