Add functions to 'pageinspect' to inspect GiST indexes.
Author: Andrey Borodin and me Discussion: https://www.postgresql.org/message-id/3E4F9093-A1B5-4DF8-A292-0B48692E3954%40yandex-team.ru
This commit is contained in:
Heikki Linnakangas
parent
df10ac625c
commit
756ab29124
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@ -7,19 +7,21 @@ OBJS = \
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btreefuncs.o \
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fsmfuncs.o \
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ginfuncs.o \
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gistfuncs.o \
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hashfuncs.o \
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heapfuncs.o \
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rawpage.o
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EXTENSION = pageinspect
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DATA = pageinspect--1.7--1.8.sql pageinspect--1.6--1.7.sql \
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DATA = pageinspect--1.8--1.9.sql \
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pageinspect--1.7--1.8.sql pageinspect--1.6--1.7.sql \
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pageinspect--1.5.sql pageinspect--1.5--1.6.sql \
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pageinspect--1.4--1.5.sql pageinspect--1.3--1.4.sql \
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pageinspect--1.2--1.3.sql pageinspect--1.1--1.2.sql \
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pageinspect--1.0--1.1.sql
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PGFILEDESC = "pageinspect - functions to inspect contents of database pages"
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REGRESS = page btree brin gin hash checksum
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REGRESS = page btree brin gin gist hash checksum
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ifdef USE_PGXS
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PG_CONFIG = pg_config
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@ -0,0 +1,87 @@
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CREATE TABLE test_gist AS SELECT point(i,i) p, i::text t FROM
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generate_series(1,1000) i;
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CREATE INDEX test_gist_idx ON test_gist USING gist (p);
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-- Page 0 is the root, the rest are leaf pages
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SELECT * FROM gist_page_opaque_info(get_raw_page('test_gist_idx', 0));
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lsn | nsn | rightlink | flags
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-----+-----+------------+-------
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0/1 | 0/0 | 4294967295 | {}
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(1 row)
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SELECT * FROM gist_page_opaque_info(get_raw_page('test_gist_idx', 1));
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lsn | nsn | rightlink | flags
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-----+-----+------------+--------
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0/1 | 0/0 | 4294967295 | {leaf}
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(1 row)
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SELECT * FROM gist_page_opaque_info(get_raw_page('test_gist_idx', 2));
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lsn | nsn | rightlink | flags
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-----+-----+-----------+--------
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0/1 | 0/0 | 1 | {leaf}
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(1 row)
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SELECT * FROM gist_page_items(get_raw_page('test_gist_idx', 0), 'test_gist_idx');
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itemoffset | ctid | itemlen | keys
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------------+-----------+---------+-------------------
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1 | (1,65535) | 40 | (p)=((166,166))
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2 | (2,65535) | 40 | (p)=((332,332))
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3 | (3,65535) | 40 | (p)=((498,498))
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4 | (4,65535) | 40 | (p)=((664,664))
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5 | (5,65535) | 40 | (p)=((830,830))
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6 | (6,65535) | 40 | (p)=((996,996))
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7 | (7,65535) | 40 | (p)=((1000,1000))
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(7 rows)
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SELECT * FROM gist_page_items(get_raw_page('test_gist_idx', 1), 'test_gist_idx') LIMIT 5;
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itemoffset | ctid | itemlen | keys
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------------+-------+---------+-------------
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1 | (0,1) | 40 | (p)=((1,1))
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2 | (0,2) | 40 | (p)=((2,2))
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3 | (0,3) | 40 | (p)=((3,3))
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4 | (0,4) | 40 | (p)=((4,4))
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5 | (0,5) | 40 | (p)=((5,5))
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(5 rows)
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SELECT * FROM gist_page_items(get_raw_page('test_gist_idx', 2), 'test_gist_idx') LIMIT 5;
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itemoffset | ctid | itemlen | keys
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------------+--------+---------+-----------------
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1 | (1,10) | 40 | (p)=((167,167))
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2 | (1,11) | 40 | (p)=((168,168))
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3 | (1,12) | 40 | (p)=((169,169))
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4 | (1,13) | 40 | (p)=((170,170))
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5 | (1,14) | 40 | (p)=((171,171))
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(5 rows)
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SELECT * FROM gist_page_items_bytea(get_raw_page('test_gist_idx', 0));
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itemoffset | ctid | itemlen | key_data
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------------+-----------+---------+------------------------------------------------------------------------------------
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1 | (1,65535) | 40 | \x00000100ffff28000000000000c064400000000000c06440000000000000f03f000000000000f03f
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2 | (2,65535) | 40 | \x00000200ffff28000000000000c074400000000000c074400000000000e064400000000000e06440
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3 | (3,65535) | 40 | \x00000300ffff28000000000000207f400000000000207f400000000000d074400000000000d07440
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4 | (4,65535) | 40 | \x00000400ffff28000000000000c084400000000000c084400000000000307f400000000000307f40
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5 | (5,65535) | 40 | \x00000500ffff28000000000000f089400000000000f089400000000000c884400000000000c88440
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6 | (6,65535) | 40 | \x00000600ffff28000000000000208f400000000000208f400000000000f889400000000000f88940
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7 | (7,65535) | 40 | \x00000700ffff28000000000000408f400000000000408f400000000000288f400000000000288f40
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(7 rows)
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SELECT * FROM gist_page_items_bytea(get_raw_page('test_gist_idx', 1)) LIMIT 5;
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itemoffset | ctid | itemlen | key_data
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------------+-------+---------+------------------------------------------------------------------------------------
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1 | (0,1) | 40 | \x0000000001002800000000000000f03f000000000000f03f000000000000f03f000000000000f03f
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2 | (0,2) | 40 | \x00000000020028000000000000000040000000000000004000000000000000400000000000000040
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3 | (0,3) | 40 | \x00000000030028000000000000000840000000000000084000000000000008400000000000000840
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4 | (0,4) | 40 | \x00000000040028000000000000001040000000000000104000000000000010400000000000001040
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5 | (0,5) | 40 | \x00000000050028000000000000001440000000000000144000000000000014400000000000001440
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(5 rows)
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SELECT * FROM gist_page_items_bytea(get_raw_page('test_gist_idx', 2)) LIMIT 5;
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itemoffset | ctid | itemlen | key_data
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------------+--------+---------+------------------------------------------------------------------------------------
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1 | (1,10) | 40 | \x000001000a0028000000000000e064400000000000e064400000000000e064400000000000e06440
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2 | (1,11) | 40 | \x000001000b0028000000000000006540000000000000654000000000000065400000000000006540
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3 | (1,12) | 40 | \x000001000c0028000000000000206540000000000020654000000000002065400000000000206540
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4 | (1,13) | 40 | \x000001000d0028000000000000406540000000000040654000000000004065400000000000406540
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5 | (1,14) | 40 | \x000001000e0028000000000000606540000000000060654000000000006065400000000000606540
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(5 rows)
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DROP TABLE test_gist;
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@ -0,0 +1,287 @@
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/*
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* gistfuncs.c
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* Functions to investigate the content of GiST indexes
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*
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* Copyright (c) 2014-2020, PostgreSQL Global Development Group
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*
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* IDENTIFICATION
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* contrib/pageinspect/gistfuncs.c
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*/
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#include "postgres.h"
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#include "access/gist.h"
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#include "access/gist_private.h"
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#include "access/htup.h"
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#include "access/relation.h"
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#include "catalog/namespace.h"
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#include "funcapi.h"
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#include "miscadmin.h"
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#include "pageinspect.h"
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#include "storage/itemptr.h"
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#include "utils/array.h"
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#include "utils/builtins.h"
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#include "utils/rel.h"
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#include "utils/pg_lsn.h"
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#include "utils/varlena.h"
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PG_FUNCTION_INFO_V1(gist_page_opaque_info);
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PG_FUNCTION_INFO_V1(gist_page_items);
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PG_FUNCTION_INFO_V1(gist_page_items_bytea);
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#define ItemPointerGetDatum(X) PointerGetDatum(X)
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Datum
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gist_page_opaque_info(PG_FUNCTION_ARGS)
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{
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bytea *raw_page = PG_GETARG_BYTEA_P(0);
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TupleDesc tupdesc;
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Page page;
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GISTPageOpaque opaq;
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HeapTuple resultTuple;
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Datum values[4];
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bool nulls[4];
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Datum flags[16];
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int nflags = 0;
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uint16 flagbits;
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if (!superuser())
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ereport(ERROR,
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(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
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errmsg("must be superuser to use raw page functions")));
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page = get_page_from_raw(raw_page);
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opaq = (GISTPageOpaque) PageGetSpecialPointer(page);
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/* Build a tuple descriptor for our result type */
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if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
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elog(ERROR, "return type must be a row type");
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/* Convert the flags bitmask to an array of human-readable names */
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flagbits = opaq->flags;
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if (flagbits & F_LEAF)
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flags[nflags++] = CStringGetTextDatum("leaf");
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if (flagbits & F_DELETED)
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flags[nflags++] = CStringGetTextDatum("deleted");
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if (flagbits & F_TUPLES_DELETED)
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flags[nflags++] = CStringGetTextDatum("tuples_deleted");
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if (flagbits & F_FOLLOW_RIGHT)
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flags[nflags++] = CStringGetTextDatum("follow_right");
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if (flagbits & F_HAS_GARBAGE)
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flags[nflags++] = CStringGetTextDatum("has_garbage");
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flagbits &= ~(F_LEAF | F_DELETED | F_TUPLES_DELETED | F_FOLLOW_RIGHT | F_HAS_GARBAGE);
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if (flagbits)
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{
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/* any flags we don't recognize are printed in hex */
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flags[nflags++] = DirectFunctionCall1(to_hex32, Int32GetDatum(flagbits));
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}
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memset(nulls, 0, sizeof(nulls));
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values[0] = LSNGetDatum(PageGetLSN(page));
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values[1] = LSNGetDatum(GistPageGetNSN(page));
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values[2] = Int64GetDatum(opaq->rightlink);
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values[3] = PointerGetDatum(construct_array(flags, nflags,
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TEXTOID,
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-1, false, TYPALIGN_INT));
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/* Build and return the result tuple. */
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resultTuple = heap_form_tuple(tupdesc, values, nulls);
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return HeapTupleGetDatum(resultTuple);
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}
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typedef struct gist_page_items_state
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{
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Page page;
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TupleDesc tupd;
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OffsetNumber offset;
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Relation rel;
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} gist_page_items_state;
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Datum
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gist_page_items_bytea(PG_FUNCTION_ARGS)
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{
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bytea *raw_page = PG_GETARG_BYTEA_P(0);
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FuncCallContext *fctx;
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gist_page_items_state *inter_call_data;
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if (!superuser())
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ereport(ERROR,
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(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
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errmsg("must be superuser to use raw page functions")));
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if (SRF_IS_FIRSTCALL())
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{
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TupleDesc tupdesc;
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MemoryContext mctx;
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Page page;
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fctx = SRF_FIRSTCALL_INIT();
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mctx = MemoryContextSwitchTo(fctx->multi_call_memory_ctx);
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page = get_page_from_raw(raw_page);
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inter_call_data = palloc(sizeof(gist_page_items_state));
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/* Build a tuple descriptor for our result type */
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if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
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elog(ERROR, "return type must be a row type");
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if (GistPageIsDeleted(page))
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elog(NOTICE, "page is deleted");
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inter_call_data->page = page;
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inter_call_data->tupd = tupdesc;
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inter_call_data->offset = FirstOffsetNumber;
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fctx->max_calls = PageGetMaxOffsetNumber(page);
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fctx->user_fctx = inter_call_data;
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MemoryContextSwitchTo(mctx);
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}
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fctx = SRF_PERCALL_SETUP();
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inter_call_data = fctx->user_fctx;
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if (fctx->call_cntr < fctx->max_calls)
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{
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Page page = inter_call_data->page;
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OffsetNumber offset = inter_call_data->offset;
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HeapTuple resultTuple;
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Datum result;
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Datum values[4];
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bool nulls[4];
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ItemId id;
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IndexTuple itup;
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bytea *tuple_bytea;
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int tuple_len;
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id = PageGetItemId(page, offset);
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if (!ItemIdIsValid(id))
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elog(ERROR, "invalid ItemId");
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itup = (IndexTuple) PageGetItem(page, id);
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tuple_len = IndexTupleSize(itup);
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memset(nulls, 0, sizeof(nulls));
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values[0] = DatumGetInt16(offset);
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values[1] = ItemPointerGetDatum(&itup->t_tid);
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values[2] = Int32GetDatum((int) IndexTupleSize(itup));
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tuple_bytea = (bytea *) palloc(tuple_len + VARHDRSZ);
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SET_VARSIZE(tuple_bytea, tuple_len + VARHDRSZ);
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memcpy(VARDATA(tuple_bytea), itup, tuple_len);
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values[3] = PointerGetDatum(tuple_bytea);
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/* Build and return the result tuple. */
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resultTuple = heap_form_tuple(inter_call_data->tupd, values, nulls);
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result = HeapTupleGetDatum(resultTuple);
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inter_call_data->offset++;
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SRF_RETURN_NEXT(fctx, result);
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}
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SRF_RETURN_DONE(fctx);
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}
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Datum
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gist_page_items(PG_FUNCTION_ARGS)
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{
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bytea *raw_page = PG_GETARG_BYTEA_P(0);
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Oid indexRelid = PG_GETARG_OID(1);
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FuncCallContext *fctx;
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gist_page_items_state *inter_call_data;
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if (!superuser())
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ereport(ERROR,
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(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
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errmsg("must be superuser to use raw page functions")));
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if (SRF_IS_FIRSTCALL())
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{
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Relation indexRel;
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TupleDesc tupdesc;
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MemoryContext mctx;
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Page page;
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fctx = SRF_FIRSTCALL_INIT();
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mctx = MemoryContextSwitchTo(fctx->multi_call_memory_ctx);
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page = get_page_from_raw(raw_page);
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inter_call_data = palloc(sizeof(gist_page_items_state));
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/* Open the relation */
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indexRel = index_open(indexRelid, AccessShareLock);
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/* Build a tuple descriptor for our result type */
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if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
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elog(ERROR, "return type must be a row type");
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if (GistPageIsDeleted(page))
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elog(NOTICE, "page is deleted");
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inter_call_data->page = page;
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inter_call_data->tupd = tupdesc;
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inter_call_data->offset = FirstOffsetNumber;
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inter_call_data->rel = indexRel;
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fctx->max_calls = PageGetMaxOffsetNumber(page);
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fctx->user_fctx = inter_call_data;
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MemoryContextSwitchTo(mctx);
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}
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fctx = SRF_PERCALL_SETUP();
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inter_call_data = fctx->user_fctx;
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if (fctx->call_cntr < fctx->max_calls)
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{
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Page page = inter_call_data->page;
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OffsetNumber offset = inter_call_data->offset;
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HeapTuple resultTuple;
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Datum result;
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Datum values[4];
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bool nulls[4];
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ItemId id;
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IndexTuple itup;
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Datum itup_values[INDEX_MAX_KEYS];
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bool itup_isnull[INDEX_MAX_KEYS];
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char *key_desc;
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id = PageGetItemId(page, offset);
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if (!ItemIdIsValid(id))
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elog(ERROR, "invalid ItemId");
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itup = (IndexTuple) PageGetItem(page, id);
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index_deform_tuple(itup, RelationGetDescr(inter_call_data->rel),
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itup_values, itup_isnull);
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key_desc = BuildIndexValueDescription(inter_call_data->rel, itup_values,
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itup_isnull);
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memset(nulls, 0, sizeof(nulls));
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values[0] = DatumGetInt16(offset);
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values[1] = ItemPointerGetDatum(&itup->t_tid);
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values[2] = Int32GetDatum((int) IndexTupleSize(itup));
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values[3] = CStringGetTextDatum(key_desc);
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/* Build and return the result tuple. */
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resultTuple = heap_form_tuple(inter_call_data->tupd, values, nulls);
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result = HeapTupleGetDatum(resultTuple);
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inter_call_data->offset++;
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SRF_RETURN_NEXT(fctx, result);
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}
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relation_close(inter_call_data->rel, AccessShareLock);
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SRF_RETURN_DONE(fctx);
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}
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@ -0,0 +1,41 @@
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/* contrib/pageinspect/pageinspect--1.8--1.9.sql */
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-- complain if script is sourced in psql, rather than via ALTER EXTENSION
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\echo Use "ALTER EXTENSION pageinspect UPDATE TO '1.9'" to load this file. \quit
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--
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-- gist_page_opaque_info()
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--
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CREATE FUNCTION gist_page_opaque_info(IN page bytea,
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OUT lsn pg_lsn,
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OUT nsn pg_lsn,
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OUT rightlink bigint,
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OUT flags text[])
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AS 'MODULE_PATHNAME', 'gist_page_opaque_info'
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LANGUAGE C STRICT PARALLEL SAFE;
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--
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-- gist_page_items_bytea()
|
||||
--
|
||||
CREATE FUNCTION gist_page_items_bytea(IN page bytea,
|
||||
OUT itemoffset smallint,
|
||||
OUT ctid tid,
|
||||
OUT itemlen smallint,
|
||||
OUT key_data bytea)
|
||||
RETURNS SETOF record
|
||||
AS 'MODULE_PATHNAME', 'gist_page_items_bytea'
|
||||
LANGUAGE C STRICT PARALLEL SAFE;
|
||||
|
||||
--
|
||||
-- gist_page_items()
|
||||
--
|
||||
CREATE FUNCTION gist_page_items(IN page bytea,
|
||||
IN index_oid regclass,
|
||||
OUT itemoffset smallint,
|
||||
OUT ctid tid,
|
||||
OUT itemlen smallint,
|
||||
OUT keys text)
|
||||
RETURNS SETOF record
|
||||
AS 'MODULE_PATHNAME', 'gist_page_items'
|
||||
LANGUAGE C STRICT PARALLEL SAFE;
|
||||
|
|
@ -1,5 +1,5 @@
|
|||
# pageinspect extension
|
||||
comment = 'inspect the contents of database pages at a low level'
|
||||
default_version = '1.8'
|
||||
default_version = '1.9'
|
||||
module_pathname = '$libdir/pageinspect'
|
||||
relocatable = true
|
||||
|
|
|
|||
|
|
@ -0,0 +1,18 @@
|
|||
CREATE TABLE test_gist AS SELECT point(i,i) p, i::text t FROM
|
||||
generate_series(1,1000) i;
|
||||
CREATE INDEX test_gist_idx ON test_gist USING gist (p);
|
||||
|
||||
-- Page 0 is the root, the rest are leaf pages
|
||||
SELECT * FROM gist_page_opaque_info(get_raw_page('test_gist_idx', 0));
|
||||
SELECT * FROM gist_page_opaque_info(get_raw_page('test_gist_idx', 1));
|
||||
SELECT * FROM gist_page_opaque_info(get_raw_page('test_gist_idx', 2));
|
||||
|
||||
SELECT * FROM gist_page_items(get_raw_page('test_gist_idx', 0), 'test_gist_idx');
|
||||
SELECT * FROM gist_page_items(get_raw_page('test_gist_idx', 1), 'test_gist_idx') LIMIT 5;
|
||||
SELECT * FROM gist_page_items(get_raw_page('test_gist_idx', 2), 'test_gist_idx') LIMIT 5;
|
||||
|
||||
SELECT * FROM gist_page_items_bytea(get_raw_page('test_gist_idx', 0));
|
||||
SELECT * FROM gist_page_items_bytea(get_raw_page('test_gist_idx', 1)) LIMIT 5;
|
||||
SELECT * FROM gist_page_items_bytea(get_raw_page('test_gist_idx', 2)) LIMIT 5;
|
||||
|
||||
DROP TABLE test_gist;
|
||||
|
|
@ -671,6 +671,95 @@ test=# SELECT first_tid, nbytes, tids[0:5] AS some_tids
|
|||
</variablelist>
|
||||
</sect2>
|
||||
|
||||
<sect2>
|
||||
<title>GiST Functions</title>
|
||||
|
||||
<variablelist>
|
||||
<varlistentry>
|
||||
<term>
|
||||
<function>gist_page_opaque_info(page bytea) returns record</function>
|
||||
<indexterm>
|
||||
<primary>gist_page_opaque_info</primary>
|
||||
</indexterm>
|
||||
</term>
|
||||
|
||||
<listitem>
|
||||
<para>
|
||||
<function>gist_page_opaque_info</function> returns information about
|
||||
a <acronym>GiST</acronym> index opaque area, like the NSN, rightlink and
|
||||
page type.
|
||||
For example:
|
||||
<screen>
|
||||
test=# SELECT * FROM gist_page_opaque_info(get_raw_page('test_gist_idx', 2));
|
||||
lsn | nsn | rightlink | flags
|
||||
-----+-----+-----------+--------
|
||||
0/1 | 0/0 | 1 | {leaf}
|
||||
(1 row)
|
||||
</screen>
|
||||
</para>
|
||||
</listitem>
|
||||
</varlistentry>
|
||||
|
||||
<varlistentry>
|
||||
<term>
|
||||
<function>gist_page_items(page bytea, index oid) returns setof record</function>
|
||||
<indexterm>
|
||||
<primary>gist_page_items</primary>
|
||||
</indexterm>
|
||||
</term>
|
||||
|
||||
<listitem>
|
||||
<para>
|
||||
<function>gist_page_items</function> returns information about
|
||||
the data stored in a page of <acronym>GiST</acronym> index. For example:
|
||||
<screen>
|
||||
test=# SELECT * FROM gist_page_items(get_raw_page('test_gist_idx', 0), 'test_gist_idx');
|
||||
itemoffset | ctid | itemlen | keys
|
||||
------------+-----------+---------+-------------------
|
||||
1 | (1,65535) | 40 | (p)=((166,166))
|
||||
2 | (2,65535) | 40 | (p)=((332,332))
|
||||
3 | (3,65535) | 40 | (p)=((498,498))
|
||||
4 | (4,65535) | 40 | (p)=((664,664))
|
||||
5 | (5,65535) | 40 | (p)=((830,830))
|
||||
6 | (6,65535) | 40 | (p)=((996,996))
|
||||
7 | (7,65535) | 40 | (p)=((1000,1000))
|
||||
(7 rows)
|
||||
</screen>
|
||||
</para>
|
||||
</listitem>
|
||||
</varlistentry>
|
||||
|
||||
<varlistentry>
|
||||
<term>
|
||||
<function>gist_page_items_bytea(page bytea) returns setof record</function>
|
||||
<indexterm>
|
||||
<primary>gist_page_items_bytea</primary>
|
||||
</indexterm>
|
||||
</term>
|
||||
|
||||
<listitem>
|
||||
<para>
|
||||
Same as <function>gist_page_items</function>, but returns the key data as a raw
|
||||
bytea blob. For example:
|
||||
<screen>
|
||||
test=# SELECT * FROM gist_page_items_bytea(get_raw_page('test_gist_idx', 0));
|
||||
itemoffset | ctid | itemlen | key_data
|
||||
------------+-----------+---------+------------------------------------------------------------------------------------
|
||||
1 | (1,65535) | 40 | \x00000100ffff28000000000000c064400000000000c06440000000000000f03f000000000000f03f
|
||||
2 | (2,65535) | 40 | \x00000200ffff28000000000000c074400000000000c074400000000000e064400000000000e06440
|
||||
3 | (3,65535) | 40 | \x00000300ffff28000000000000207f400000000000207f400000000000d074400000000000d07440
|
||||
4 | (4,65535) | 40 | \x00000400ffff28000000000000c084400000000000c084400000000000307f400000000000307f40
|
||||
5 | (5,65535) | 40 | \x00000500ffff28000000000000f089400000000000f089400000000000c884400000000000c88440
|
||||
6 | (6,65535) | 40 | \x00000600ffff28000000000000208f400000000000208f400000000000f889400000000000f88940
|
||||
7 | (7,65535) | 40 | \x00000700ffff28000000000000408f400000000000408f400000000000288f400000000000288f40
|
||||
(7 rows)
|
||||
</screen>
|
||||
</para>
|
||||
</listitem>
|
||||
</varlistentry>
|
||||
</variablelist>
|
||||
</sect2>
|
||||
|
||||
<sect2>
|
||||
<title>Hash Functions</title>
|
||||
|
||||
|
|
|
|||
Loading…
Reference in New Issue