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Our usual practice for "poor man's enum" catalog columns is to define macros for the possible values and use those, not literal constants, in C code. But for some reason lost in the mists of time, this was never done for typalign/attalign or typstorage/attstorage. It's never too late to make it better though, so let's do that. The reason I got interested in this right now is the need to duplicate some uses of the TYPSTORAGE constants in an upcoming ALTER TYPE patch. But in general, this sort of change aids greppability and readability, so it's a good idea even without any specific motivation. I may have missed a few places that could be converted, and it's even more likely that pending patches will re-introduce some hard-coded references. But that's not fatal --- there's no expectation that we'd actually change any of these values. We can clean up stragglers over time. Discussion: https://postgr.es/m/16457.1583189537@sss.pgh.pa.us
693 lines
19 KiB
C
693 lines
19 KiB
C
/*
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* contrib/pageinspect/btreefuncs.c
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*
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*
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* btreefuncs.c
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*
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* Copyright (c) 2006 Satoshi Nagayasu <nagayasus@nttdata.co.jp>
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*
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* Permission to use, copy, modify, and distribute this software and
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* its documentation for any purpose, without fee, and without a
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* written agreement is hereby granted, provided that the above
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* copyright notice and this paragraph and the following two
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* paragraphs appear in all copies.
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*
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* IN NO EVENT SHALL THE AUTHOR BE LIABLE TO ANY PARTY FOR DIRECT,
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* INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING
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* LOST PROFITS, ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS
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* DOCUMENTATION, EVEN IF THE UNIVERSITY OF CALIFORNIA HAS BEEN ADVISED
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* OF THE POSSIBILITY OF SUCH DAMAGE.
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*
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* THE AUTHOR SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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* A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS ON AN "AS
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* IS" BASIS, AND THE AUTHOR HAS NO OBLIGATIONS TO PROVIDE MAINTENANCE,
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* SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
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*/
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#include "postgres.h"
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#include "access/nbtree.h"
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#include "access/relation.h"
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#include "catalog/namespace.h"
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#include "catalog/pg_am.h"
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#include "catalog/pg_type.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 "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/varlena.h"
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PG_FUNCTION_INFO_V1(bt_metap);
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PG_FUNCTION_INFO_V1(bt_page_items);
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PG_FUNCTION_INFO_V1(bt_page_items_bytea);
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PG_FUNCTION_INFO_V1(bt_page_stats);
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#define IS_INDEX(r) ((r)->rd_rel->relkind == RELKIND_INDEX)
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#define IS_BTREE(r) ((r)->rd_rel->relam == BTREE_AM_OID)
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#define DatumGetItemPointer(X) ((ItemPointer) DatumGetPointer(X))
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#define ItemPointerGetDatum(X) PointerGetDatum(X)
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/* note: BlockNumber is unsigned, hence can't be negative */
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#define CHECK_RELATION_BLOCK_RANGE(rel, blkno) { \
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if ( RelationGetNumberOfBlocks(rel) <= (BlockNumber) (blkno) ) \
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elog(ERROR, "block number out of range"); }
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/* ------------------------------------------------
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* structure for single btree page statistics
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* ------------------------------------------------
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*/
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typedef struct BTPageStat
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{
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uint32 blkno;
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uint32 live_items;
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uint32 dead_items;
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uint32 page_size;
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uint32 max_avail;
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uint32 free_size;
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uint32 avg_item_size;
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char type;
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/* opaque data */
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BlockNumber btpo_prev;
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BlockNumber btpo_next;
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union
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{
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uint32 level;
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TransactionId xact;
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} btpo;
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uint16 btpo_flags;
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BTCycleId btpo_cycleid;
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} BTPageStat;
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/* -------------------------------------------------
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* GetBTPageStatistics()
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*
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* Collect statistics of single b-tree page
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* -------------------------------------------------
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*/
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static void
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GetBTPageStatistics(BlockNumber blkno, Buffer buffer, BTPageStat *stat)
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{
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Page page = BufferGetPage(buffer);
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PageHeader phdr = (PageHeader) page;
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OffsetNumber maxoff = PageGetMaxOffsetNumber(page);
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BTPageOpaque opaque = (BTPageOpaque) PageGetSpecialPointer(page);
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int item_size = 0;
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int off;
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stat->blkno = blkno;
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stat->max_avail = BLCKSZ - (BLCKSZ - phdr->pd_special + SizeOfPageHeaderData);
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stat->dead_items = stat->live_items = 0;
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stat->page_size = PageGetPageSize(page);
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/* page type (flags) */
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if (P_ISDELETED(opaque))
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{
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stat->type = 'd';
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stat->btpo.xact = opaque->btpo.xact;
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return;
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}
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else if (P_IGNORE(opaque))
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stat->type = 'e';
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else if (P_ISLEAF(opaque))
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stat->type = 'l';
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else if (P_ISROOT(opaque))
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stat->type = 'r';
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else
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stat->type = 'i';
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/* btpage opaque data */
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stat->btpo_prev = opaque->btpo_prev;
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stat->btpo_next = opaque->btpo_next;
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stat->btpo.level = opaque->btpo.level;
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stat->btpo_flags = opaque->btpo_flags;
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stat->btpo_cycleid = opaque->btpo_cycleid;
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/* count live and dead tuples, and free space */
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for (off = FirstOffsetNumber; off <= maxoff; off++)
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{
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IndexTuple itup;
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ItemId id = PageGetItemId(page, off);
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itup = (IndexTuple) PageGetItem(page, id);
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item_size += IndexTupleSize(itup);
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if (!ItemIdIsDead(id))
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stat->live_items++;
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else
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stat->dead_items++;
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}
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stat->free_size = PageGetFreeSpace(page);
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if ((stat->live_items + stat->dead_items) > 0)
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stat->avg_item_size = item_size / (stat->live_items + stat->dead_items);
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else
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stat->avg_item_size = 0;
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}
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/* -----------------------------------------------
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* bt_page_stats()
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*
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* Usage: SELECT * FROM bt_page_stats('t1_pkey', 1);
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* -----------------------------------------------
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*/
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Datum
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bt_page_stats(PG_FUNCTION_ARGS)
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{
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text *relname = PG_GETARG_TEXT_PP(0);
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uint32 blkno = PG_GETARG_UINT32(1);
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Buffer buffer;
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Relation rel;
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RangeVar *relrv;
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Datum result;
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HeapTuple tuple;
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TupleDesc tupleDesc;
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int j;
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char *values[11];
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BTPageStat stat;
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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 pageinspect functions")));
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relrv = makeRangeVarFromNameList(textToQualifiedNameList(relname));
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rel = relation_openrv(relrv, AccessShareLock);
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if (!IS_INDEX(rel) || !IS_BTREE(rel))
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elog(ERROR, "relation \"%s\" is not a btree index",
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RelationGetRelationName(rel));
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/*
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* Reject attempts to read non-local temporary relations; we would be
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* likely to get wrong data since we have no visibility into the owning
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* session's local buffers.
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*/
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if (RELATION_IS_OTHER_TEMP(rel))
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ereport(ERROR,
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(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
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errmsg("cannot access temporary tables of other sessions")));
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if (blkno == 0)
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elog(ERROR, "block 0 is a meta page");
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CHECK_RELATION_BLOCK_RANGE(rel, blkno);
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buffer = ReadBuffer(rel, blkno);
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LockBuffer(buffer, BUFFER_LOCK_SHARE);
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/* keep compiler quiet */
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stat.btpo_prev = stat.btpo_next = InvalidBlockNumber;
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stat.btpo_flags = stat.free_size = stat.avg_item_size = 0;
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GetBTPageStatistics(blkno, buffer, &stat);
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UnlockReleaseBuffer(buffer);
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relation_close(rel, AccessShareLock);
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/* Build a tuple descriptor for our result type */
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if (get_call_result_type(fcinfo, NULL, &tupleDesc) != TYPEFUNC_COMPOSITE)
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elog(ERROR, "return type must be a row type");
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j = 0;
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values[j++] = psprintf("%d", stat.blkno);
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values[j++] = psprintf("%c", stat.type);
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values[j++] = psprintf("%d", stat.live_items);
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values[j++] = psprintf("%d", stat.dead_items);
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values[j++] = psprintf("%d", stat.avg_item_size);
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values[j++] = psprintf("%d", stat.page_size);
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values[j++] = psprintf("%d", stat.free_size);
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values[j++] = psprintf("%d", stat.btpo_prev);
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values[j++] = psprintf("%d", stat.btpo_next);
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values[j++] = psprintf("%d", (stat.type == 'd') ? stat.btpo.xact : stat.btpo.level);
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values[j++] = psprintf("%d", stat.btpo_flags);
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tuple = BuildTupleFromCStrings(TupleDescGetAttInMetadata(tupleDesc),
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values);
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result = HeapTupleGetDatum(tuple);
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PG_RETURN_DATUM(result);
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}
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/*
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* cross-call data structure for SRF
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*/
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struct user_args
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{
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Page page;
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OffsetNumber offset;
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bool leafpage;
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bool rightmost;
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TupleDesc tupd;
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};
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/*-------------------------------------------------------
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* bt_page_print_tuples()
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*
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* Form a tuple describing index tuple at a given offset
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* ------------------------------------------------------
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*/
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static Datum
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bt_page_print_tuples(FuncCallContext *fctx, struct user_args *uargs)
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{
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Page page = uargs->page;
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OffsetNumber offset = uargs->offset;
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bool leafpage = uargs->leafpage;
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bool rightmost = uargs->rightmost;
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bool ispivottuple;
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Datum values[9];
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bool nulls[9];
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HeapTuple tuple;
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ItemId id;
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IndexTuple itup;
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int j;
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int off;
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int dlen;
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char *dump,
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*datacstring;
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char *ptr;
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ItemPointer htid;
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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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j = 0;
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memset(nulls, 0, sizeof(nulls));
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values[j++] = DatumGetInt16(offset);
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values[j++] = ItemPointerGetDatum(&itup->t_tid);
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values[j++] = Int32GetDatum((int) IndexTupleSize(itup));
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values[j++] = BoolGetDatum(IndexTupleHasNulls(itup));
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values[j++] = BoolGetDatum(IndexTupleHasVarwidths(itup));
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ptr = (char *) itup + IndexInfoFindDataOffset(itup->t_info);
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dlen = IndexTupleSize(itup) - IndexInfoFindDataOffset(itup->t_info);
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/*
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* Make sure that "data" column does not include posting list or pivot
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* tuple representation of heap TID(s).
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*
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* Note: BTreeTupleIsPivot() won't work reliably on !heapkeyspace indexes
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* (those built before BTREE_VERSION 4), but we have no way of determining
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* if this page came from a !heapkeyspace index. We may only have a bytea
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* nbtree page image to go on, so in general there is no metapage that we
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* can check.
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*
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* That's okay here because BTreeTupleIsPivot() can only return false for
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* a !heapkeyspace pivot, never true for a !heapkeyspace non-pivot. Since
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* heap TID isn't part of the keyspace in a !heapkeyspace index anyway,
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* there cannot possibly be a pivot tuple heap TID representation that we
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* fail to make an adjustment for. A !heapkeyspace index can have
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* BTreeTupleIsPivot() return true (due to things like suffix truncation
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* for INCLUDE indexes in Postgres v11), but when that happens
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* BTreeTupleGetHeapTID() can be trusted to work reliably (i.e. return
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* NULL).
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*
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* Note: BTreeTupleIsPosting() always works reliably, even with
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* !heapkeyspace indexes.
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*/
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if (BTreeTupleIsPosting(itup))
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dlen -= IndexTupleSize(itup) - BTreeTupleGetPostingOffset(itup);
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else if (BTreeTupleIsPivot(itup) && BTreeTupleGetHeapTID(itup) != NULL)
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dlen -= MAXALIGN(sizeof(ItemPointerData));
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if (dlen < 0 || dlen > INDEX_SIZE_MASK)
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elog(ERROR, "invalid tuple length %d for tuple at offset number %u",
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dlen, offset);
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dump = palloc0(dlen * 3 + 1);
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datacstring = dump;
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for (off = 0; off < dlen; off++)
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{
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if (off > 0)
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*dump++ = ' ';
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sprintf(dump, "%02x", *(ptr + off) & 0xff);
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dump += 2;
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}
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values[j++] = CStringGetTextDatum(datacstring);
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pfree(datacstring);
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/*
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* We need to work around the BTreeTupleIsPivot() !heapkeyspace limitation
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* again. Deduce whether or not tuple must be a pivot tuple based on
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* whether or not the page is a leaf page, as well as the page offset
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* number of the tuple.
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*/
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ispivottuple = (!leafpage || (!rightmost && offset == P_HIKEY));
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/* LP_DEAD bit can never be set for pivot tuples, so show a NULL there */
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if (!ispivottuple)
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values[j++] = BoolGetDatum(ItemIdIsDead(id));
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else
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{
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Assert(!ItemIdIsDead(id));
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nulls[j++] = true;
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}
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htid = BTreeTupleGetHeapTID(itup);
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if (ispivottuple && !BTreeTupleIsPivot(itup))
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{
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/* Don't show bogus heap TID in !heapkeyspace pivot tuple */
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htid = NULL;
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}
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if (htid)
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values[j++] = ItemPointerGetDatum(htid);
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else
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nulls[j++] = true;
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if (BTreeTupleIsPosting(itup))
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{
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/* Build an array of item pointers */
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ItemPointer tids;
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Datum *tids_datum;
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int nposting;
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tids = BTreeTupleGetPosting(itup);
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nposting = BTreeTupleGetNPosting(itup);
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tids_datum = (Datum *) palloc(nposting * sizeof(Datum));
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for (int i = 0; i < nposting; i++)
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tids_datum[i] = ItemPointerGetDatum(&tids[i]);
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values[j++] = PointerGetDatum(construct_array(tids_datum,
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nposting,
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TIDOID,
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sizeof(ItemPointerData),
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false, TYPALIGN_SHORT));
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pfree(tids_datum);
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}
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else
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nulls[j++] = true;
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/* Build and return the result tuple */
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tuple = heap_form_tuple(uargs->tupd, values, nulls);
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return HeapTupleGetDatum(tuple);
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}
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/*-------------------------------------------------------
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* bt_page_items()
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*
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* Get IndexTupleData set in a btree page
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*
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* Usage: SELECT * FROM bt_page_items('t1_pkey', 1);
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*-------------------------------------------------------
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*/
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Datum
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bt_page_items(PG_FUNCTION_ARGS)
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{
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text *relname = PG_GETARG_TEXT_PP(0);
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uint32 blkno = PG_GETARG_UINT32(1);
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Datum result;
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FuncCallContext *fctx;
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MemoryContext mctx;
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struct user_args *uargs;
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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 pageinspect functions")));
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if (SRF_IS_FIRSTCALL())
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{
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RangeVar *relrv;
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Relation rel;
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Buffer buffer;
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BTPageOpaque opaque;
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TupleDesc tupleDesc;
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fctx = SRF_FIRSTCALL_INIT();
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relrv = makeRangeVarFromNameList(textToQualifiedNameList(relname));
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rel = relation_openrv(relrv, AccessShareLock);
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if (!IS_INDEX(rel) || !IS_BTREE(rel))
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elog(ERROR, "relation \"%s\" is not a btree index",
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RelationGetRelationName(rel));
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/*
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* Reject attempts to read non-local temporary relations; we would be
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* likely to get wrong data since we have no visibility into the
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* owning session's local buffers.
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*/
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if (RELATION_IS_OTHER_TEMP(rel))
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ereport(ERROR,
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(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
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errmsg("cannot access temporary tables of other sessions")));
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if (blkno == 0)
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elog(ERROR, "block 0 is a meta page");
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CHECK_RELATION_BLOCK_RANGE(rel, blkno);
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buffer = ReadBuffer(rel, blkno);
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LockBuffer(buffer, BUFFER_LOCK_SHARE);
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/*
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* We copy the page into local storage to avoid holding pin on the
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* buffer longer than we must, and possibly failing to release it at
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* all if the calling query doesn't fetch all rows.
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*/
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mctx = MemoryContextSwitchTo(fctx->multi_call_memory_ctx);
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uargs = palloc(sizeof(struct user_args));
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uargs->page = palloc(BLCKSZ);
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memcpy(uargs->page, BufferGetPage(buffer), BLCKSZ);
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UnlockReleaseBuffer(buffer);
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relation_close(rel, AccessShareLock);
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uargs->offset = FirstOffsetNumber;
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opaque = (BTPageOpaque) PageGetSpecialPointer(uargs->page);
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if (P_ISDELETED(opaque))
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elog(NOTICE, "page is deleted");
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fctx->max_calls = PageGetMaxOffsetNumber(uargs->page);
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uargs->leafpage = P_ISLEAF(opaque);
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uargs->rightmost = P_RIGHTMOST(opaque);
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/* Build a tuple descriptor for our result type */
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if (get_call_result_type(fcinfo, NULL, &tupleDesc) != TYPEFUNC_COMPOSITE)
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elog(ERROR, "return type must be a row type");
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tupleDesc = BlessTupleDesc(tupleDesc);
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uargs->tupd = tupleDesc;
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fctx->user_fctx = uargs;
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MemoryContextSwitchTo(mctx);
|
|
}
|
|
|
|
fctx = SRF_PERCALL_SETUP();
|
|
uargs = fctx->user_fctx;
|
|
|
|
if (fctx->call_cntr < fctx->max_calls)
|
|
{
|
|
result = bt_page_print_tuples(fctx, uargs);
|
|
uargs->offset++;
|
|
SRF_RETURN_NEXT(fctx, result);
|
|
}
|
|
else
|
|
{
|
|
pfree(uargs->page);
|
|
pfree(uargs);
|
|
SRF_RETURN_DONE(fctx);
|
|
}
|
|
}
|
|
|
|
/*-------------------------------------------------------
|
|
* bt_page_items_bytea()
|
|
*
|
|
* Get IndexTupleData set in a btree page
|
|
*
|
|
* Usage: SELECT * FROM bt_page_items(get_raw_page('t1_pkey', 1));
|
|
*-------------------------------------------------------
|
|
*/
|
|
|
|
Datum
|
|
bt_page_items_bytea(PG_FUNCTION_ARGS)
|
|
{
|
|
bytea *raw_page = PG_GETARG_BYTEA_P(0);
|
|
Datum result;
|
|
FuncCallContext *fctx;
|
|
struct user_args *uargs;
|
|
int raw_page_size;
|
|
|
|
if (!superuser())
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
|
|
errmsg("must be superuser to use raw page functions")));
|
|
|
|
if (SRF_IS_FIRSTCALL())
|
|
{
|
|
BTPageOpaque opaque;
|
|
MemoryContext mctx;
|
|
TupleDesc tupleDesc;
|
|
|
|
raw_page_size = VARSIZE(raw_page) - VARHDRSZ;
|
|
|
|
if (raw_page_size < SizeOfPageHeaderData)
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
|
|
errmsg("input page too small (%d bytes)", raw_page_size)));
|
|
|
|
fctx = SRF_FIRSTCALL_INIT();
|
|
mctx = MemoryContextSwitchTo(fctx->multi_call_memory_ctx);
|
|
|
|
uargs = palloc(sizeof(struct user_args));
|
|
|
|
uargs->page = VARDATA(raw_page);
|
|
|
|
uargs->offset = FirstOffsetNumber;
|
|
|
|
opaque = (BTPageOpaque) PageGetSpecialPointer(uargs->page);
|
|
|
|
if (P_ISMETA(opaque))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
|
|
errmsg("block is a meta page")));
|
|
|
|
if (P_ISDELETED(opaque))
|
|
elog(NOTICE, "page is deleted");
|
|
|
|
fctx->max_calls = PageGetMaxOffsetNumber(uargs->page);
|
|
uargs->leafpage = P_ISLEAF(opaque);
|
|
uargs->rightmost = P_RIGHTMOST(opaque);
|
|
|
|
/* Build a tuple descriptor for our result type */
|
|
if (get_call_result_type(fcinfo, NULL, &tupleDesc) != TYPEFUNC_COMPOSITE)
|
|
elog(ERROR, "return type must be a row type");
|
|
tupleDesc = BlessTupleDesc(tupleDesc);
|
|
|
|
uargs->tupd = tupleDesc;
|
|
|
|
fctx->user_fctx = uargs;
|
|
|
|
MemoryContextSwitchTo(mctx);
|
|
}
|
|
|
|
fctx = SRF_PERCALL_SETUP();
|
|
uargs = fctx->user_fctx;
|
|
|
|
if (fctx->call_cntr < fctx->max_calls)
|
|
{
|
|
result = bt_page_print_tuples(fctx, uargs);
|
|
uargs->offset++;
|
|
SRF_RETURN_NEXT(fctx, result);
|
|
}
|
|
else
|
|
{
|
|
pfree(uargs);
|
|
SRF_RETURN_DONE(fctx);
|
|
}
|
|
}
|
|
|
|
|
|
/* ------------------------------------------------
|
|
* bt_metap()
|
|
*
|
|
* Get a btree's meta-page information
|
|
*
|
|
* Usage: SELECT * FROM bt_metap('t1_pkey')
|
|
* ------------------------------------------------
|
|
*/
|
|
Datum
|
|
bt_metap(PG_FUNCTION_ARGS)
|
|
{
|
|
text *relname = PG_GETARG_TEXT_PP(0);
|
|
Datum result;
|
|
Relation rel;
|
|
RangeVar *relrv;
|
|
BTMetaPageData *metad;
|
|
TupleDesc tupleDesc;
|
|
int j;
|
|
char *values[9];
|
|
Buffer buffer;
|
|
Page page;
|
|
HeapTuple tuple;
|
|
|
|
if (!superuser())
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_INSUFFICIENT_PRIVILEGE),
|
|
errmsg("must be superuser to use pageinspect functions")));
|
|
|
|
relrv = makeRangeVarFromNameList(textToQualifiedNameList(relname));
|
|
rel = relation_openrv(relrv, AccessShareLock);
|
|
|
|
if (!IS_INDEX(rel) || !IS_BTREE(rel))
|
|
elog(ERROR, "relation \"%s\" is not a btree index",
|
|
RelationGetRelationName(rel));
|
|
|
|
/*
|
|
* Reject attempts to read non-local temporary relations; we would be
|
|
* likely to get wrong data since we have no visibility into the owning
|
|
* session's local buffers.
|
|
*/
|
|
if (RELATION_IS_OTHER_TEMP(rel))
|
|
ereport(ERROR,
|
|
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
|
|
errmsg("cannot access temporary tables of other sessions")));
|
|
|
|
buffer = ReadBuffer(rel, 0);
|
|
LockBuffer(buffer, BUFFER_LOCK_SHARE);
|
|
|
|
page = BufferGetPage(buffer);
|
|
metad = BTPageGetMeta(page);
|
|
|
|
/* Build a tuple descriptor for our result type */
|
|
if (get_call_result_type(fcinfo, NULL, &tupleDesc) != TYPEFUNC_COMPOSITE)
|
|
elog(ERROR, "return type must be a row type");
|
|
|
|
j = 0;
|
|
values[j++] = psprintf("%d", metad->btm_magic);
|
|
values[j++] = psprintf("%d", metad->btm_version);
|
|
values[j++] = psprintf("%d", metad->btm_root);
|
|
values[j++] = psprintf("%d", metad->btm_level);
|
|
values[j++] = psprintf("%d", metad->btm_fastroot);
|
|
values[j++] = psprintf("%d", metad->btm_fastlevel);
|
|
|
|
/*
|
|
* Get values of extended metadata if available, use default values
|
|
* otherwise. Note that we rely on the assumption that btm_allequalimage
|
|
* is initialized to zero with indexes that were built on versions prior
|
|
* to Postgres 13 (just like _bt_metaversion()).
|
|
*/
|
|
if (metad->btm_version >= BTREE_NOVAC_VERSION)
|
|
{
|
|
values[j++] = psprintf("%u", metad->btm_oldest_btpo_xact);
|
|
values[j++] = psprintf("%f", metad->btm_last_cleanup_num_heap_tuples);
|
|
values[j++] = metad->btm_allequalimage ? "t" : "f";
|
|
}
|
|
else
|
|
{
|
|
values[j++] = "0";
|
|
values[j++] = "-1";
|
|
values[j++] = "f";
|
|
}
|
|
|
|
tuple = BuildTupleFromCStrings(TupleDescGetAttInMetadata(tupleDesc),
|
|
values);
|
|
|
|
result = HeapTupleGetDatum(tuple);
|
|
|
|
UnlockReleaseBuffer(buffer);
|
|
relation_close(rel, AccessShareLock);
|
|
|
|
PG_RETURN_DATUM(result);
|
|
}
|