--- /dev/null
+pgstattuple README 2001/10/01 Tatsuo Ishii
+
+1. What is pgstattuple?
+
+ pgstattuple returns the percentage of the "dead" tuples of a
+ table. This will help users to judge if vacuum is needed.
+
+ In addition, pgstattuple prints more detailed information using
+ NOTICE.
+
+test=# select pgstattuple('tellers');
+NOTICE: physical length: 0.08MB live tuples: 20 (0.00MB, 1.17%) dead tuples: 320 (0.01MB, 18.75%) free/reusable space: 0.01MB (18.06%) overhead: 62.02%
+ pgstattuple
+-------------
+ 18.75
+(1 row)
+
+ Above example shows tellers tables includes 18.75% dead tuples.
+
+ physical length physical size of the table in MB
+ live tuples information on the live tuples
+ dead tuples information on the dead tuples
+ free/reusable space available space
+ overhead overhead space
+
+2. Installing pgstattuple
+
+ $ make
+ $ make install
+ $ psql -e -f /usr/local/pgsql/share/contrib/pgstattuple.sql test
+
+3. Using pgstattuple
+
+ pgstattuple can be called as a function:
+
+ pgstattuple(NAME) RETURNS FLOAT8
+
+ The argument is the table name. pgstattuple returns the percentage
+ of the "dead" tuples of a table.
+
+4. Notes
+
+ pgstattuple does not lock the target table at all. So concurrent
+ update may affect the result.
+
+ pgstattuple judges a tuple is "dead" if HeapTupleSatisfiesNow()
+ returns false.
--- /dev/null
+$Id: README.pgstattuple.euc_jp,v 1.1 2001/10/01 01:52:38 ishii Exp $
+
+pgstattuple README 2001/10/01 ÀаæãÉ×
+
+1. pgstattuple¤È¤Ï
+
+ pgstattuple¤Ï¡¤UPDATE¤äDELETE¤Çºî¤é¤ì¤¿¥Æ¡¼¥Ö¥ë¤Î¥´¥ßÎΰè¤ÎÂ礤µ¤ò¡¤
+ ¥Æ¡¼¥Ö¥ë¼«ÂΤÎʪÍýŪ¤ÊÂ礤µ¤ËÂФ¹¤ë¥Ñ¡¼¥»¥ó¥Æ¡¼¥¸¤ÇÊֵѤ·¤Þ¤¹¡¥¤Ä
+ ¤Þ¤ê¡¤ÊÖµÑÃͤ¬Â礤±¤ì¤Ð¡¤¤½¤ì¤À¤±¥´¥ß¤â¿¤¤¤Î¤Ç¡¤vacuum¤ò¤«¤±¤ëɬ
+ Íפ¬¤¢¤ë¤È¤¤¤¦È½ÃǤνõ¤±¤Ë¤Ê¤ë¤ï¤±¤Ç¤¹¡¥
+
+ ¤³¤ì¤À¤±¤Ç¤Ï¾ðÊóÎ̤¬¾¯¤Ê¤¤¤Î¤Ç¡¤NOTICE¥á¥Ã¥»¡¼¥¸¤Ç¤¤¤í¤ó¤Ê¾ðÊó¤ò¤Ä
+ ¤¤¤Ç¤Ë½ÐÎϤ·¤Þ¤¹¡¥
+
+test=# select pgstattuple('tellers');
+NOTICE: physical length: 0.08MB live tuples: 20 (0.00MB, 1.17%) dead tuples: 320 (0.01MB, 18.75%) free/reusable space: 0.01MB (18.06%) overhead: 62.02%
+ pgstattuple
+-------------
+ 18.75
+(1 row)
+
+ ¤³¤Î¼Â¹ÔÎã¤Ç¤Ï¡¤19%¤Û¤É¤¬¥´¥ß¤Ë¤Ê¤Ã¤Æ¤¤¤ë¤³¤È¤¬»Ç¤¨¤Þ¤¹¡¥NOTICE¥á¥Ã
+ ¥»¡¼¥¸¤Î¸«Êý¤â½ñ¤¤¤Æ¤ª¤¤Þ¤¹¡¥
+
+ physical length ¥Æ¡¼¥Ö¥ë¤ÎʪÍýŪ¤Ê¥µ¥¤¥º¤òMBñ°Ì¤Çɽ¼¨
+ live tuples ¥´¥ß¤Ç¤Ï¤Ê¤¤¥¿¥×¥ë¤Ë´Ø¤¹¤ë¾ðÊó¡¥¥¿¥×¥ë¿ô¡¤³Æ
+ ¥¿¥×¥ë¤¬Àê¤á¤ëÎΰè¤Î¹ç·×¡¤¥Æ¡¼¥Ö¥ëÁ´ÂΤËÂФ¹¤ë
+ ÈæΨ¤òɽ¼¨¤·¤Þ¤¹¡¥
+ dead tuples ¥´¥ß¤Ë¤Ê¤Ã¤¿¥¿¥×¥ë¤Ë´Ø¤¹¤ë¾ðÊó¡¥
+ free/reusable space ÍøÍѲÄǽ¤Ê̤»ÈÍÑÎΰè¤äºÆÍøÍѲÄǽÎΰè
+ overhead ´ÉÍý¤Î¤¿¤á¤ÎÎΰ褬¥Æ¡¼¥Ö¥ëÁ´ÂΤËÀê¤á¤ëÈæΨ
+
+2. pgstattuple¤Î¥¤¥ó¥¹¥È¡¼¥ë
+
+ PostgreSQL¤¬/usr/local/pgsql¤Ë¥¤¥ó¥¹¥È¡¼¥ëºÑ¤Ç¤¢¤ê¡¤test¥Ç¡¼¥¿¥Ù¡¼
+ ¥¹¤Ëpgstattuple¤ò¥¤¥ó¥¹¥È¡¼¥ë¤¹¤ë¾ì¹ç¤Î¼ê½ç¤ò¼¨¤·¤Þ¤¹¡¥
+
+ $ make
+ $ make install
+
+ ¥æ¡¼¥¶ÄêµÁ´Ø¿ô¤òÅÐÏ¿¤·¤Þ¤¹¡¥
+
+ $ psql -e -f /usr/local/pgsql/share/contrib/pgstattuple.sql test
+
+
+3. pgstattuple¤Î»È¤¤Êý
+
+ pgstattuple¤Î¸Æ¤Ó½Ð¤··Á¼°¤Ï°Ê²¼¤Ç¤¹¡¥
+
+ pgstattuple(NAME) RETURNS FLOAT8
+
+ Âè°ì°ú¿ô: ¥Æ¡¼¥Ö¥ë̾
+
+ ´Ø¿ô¤ÎÌá¤ê¤ÏUPDATE¤äDELETE¤Çºî¤é¤ì¤¿¥Æ¡¼¥Ö¥ë¤Î¥´¥ßÎΰè¤ÎÂ礤µ¤Ç¡¤
+ ¥Æ¡¼¥Ö¥ë¤ÎʪÍýŪ¤ÊÂ礤µ¤ËÂФ¹¤ë³ä¹ç(¥Ñ¡¼¥»¥ó¥È)¤ÇÊֵѤ·¤Þ¤¹¡¥
+
+ ¤Ê¤ª¡¤pgstattuple¤Ï¥Æ¡¼¥Ö¥ë¤Ë°ìÀÚ¥í¥Ã¥¯¤ò¤«¤±¤Ê¤¤¤Î¤Ç¡¤pgstattuple
+ ¤ò¼Â¹ÔÃæ¤Ë³ºÅö¥Æ¡¼¥Ö¥ë¤Ë¹¹¿·¤äºï½ü¤¬È¯À¸¤¹¤ë¤È¡¤Àµ¤·¤¯¤Ê¤¤·ë²Ì¤òÊÖ
+ ¤¹²ÄǽÀ¤¬¤¢¤ê¤Þ¤¹¡¥
+
+4. pgstattuple¤Î¥é¥¤¥»¥ó¥¹¾ò·ï¤Ë¤Ä¤¤¤Æ
+
+ pgstattuple.c¤ÎËÁƬ¤Ë½ñ¤¤¤Æ¤¢¤ëÄ̤ê¤Ç¤¹¡¥¤Þ¤¿¡¤pgstattuple ¤Ï´°Á´¤Ë̵ÊÝ
+ ¾Ú¤Ç¤¹¡¥pgstattuple ¤ò»ÈÍѤ·¤¿¤³¤È¤Ë¤è¤Ã¤ÆÀ¸¤¸¤ë¤¤¤«¤Ê¤ë·ë²Ì¤Ë´Ø¤·¤Æ
+ ¤âÀÕǤ¤òÉ餤¤Þ¤»¤ó¡¥
+
+5. ²þÄûÍúÎò
+
+ 2001/10/01 PostgreSQL 7.2 ÍÑcontrib module¤ËÅÐÏ¿
+ 2001/08/30 pgstattuple ¥Ð¡¼¥¸¥ç¥ó 0.1¥ê¥ê¡¼¥¹
--- /dev/null
+/*
+ * $Header: /cvsroot/pgsql/contrib/pgstattuple/pgstattuple.c,v 1.1 2001/10/01 01:52:38 ishii Exp $
+ *
+ * Copyright (c) 2001 Tatsuo Ishii
+ *
+ * Permission to use, copy, modify, and distribute this software and
+ * its documentation for any purpose, without fee, and without a
+ * written agreement is hereby granted, provided that the above
+ * copyright notice and this paragraph and the following two
+ * paragraphs appear in all copies.
+ *
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE TO ANY PARTY FOR DIRECT,
+ * INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING
+ * LOST PROFITS, ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS
+ * DOCUMENTATION, EVEN IF THE UNIVERSITY OF CALIFORNIA HAS BEEN ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * THE AUTHOR SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS ON AN "AS
+ * IS" BASIS, AND THE AUTHOR HAS NO OBLIGATIONS TO PROVIDE MAINTENANCE,
+ * SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+ */
+
+#include "postgres.h"
+#include "fmgr.h"
+#include "access/heapam.h"
+#include "access/transam.h"
+
+PG_FUNCTION_INFO_V1(pgstattuple);
+
+extern Datum pgstattuple(PG_FUNCTION_ARGS);
+
+/* ----------
+ * pgstattuple:
+ * returns the percentage of dead tuples
+ *
+ * C FUNCTION definition
+ * pgstattuple(NAME) returns FLOAT8
+ * ----------
+ */
+Datum
+pgstattuple(PG_FUNCTION_ARGS)
+{
+ Name p = PG_GETARG_NAME(0);
+
+ Relation rel;
+ HeapScanDesc scan;
+ HeapTuple tuple;
+ BlockNumber nblocks;
+ BlockNumber block = InvalidBlockNumber;
+ double table_len;
+ uint64 tuple_len = 0;
+ uint64 dead_tuple_len = 0;
+ uint32 tuple_count = 0;
+ uint32 dead_tuple_count = 0;
+ double tuple_percent;
+ double dead_tuple_percent;
+
+ Buffer buffer = InvalidBuffer;
+ uint64 free_space = 0; /* free/reusable space in bytes */
+ double free_percent; /* free/reusable space in % */
+
+ rel = heap_openr(NameStr(*p), NoLock);
+ nblocks = RelationGetNumberOfBlocks(rel);
+ scan = heap_beginscan(rel, false, SnapshotAny, 0, NULL);
+
+ while ((tuple = heap_getnext(scan,0)))
+ {
+ if (HeapTupleSatisfiesNow(tuple->t_data))
+ {
+ tuple_len += tuple->t_len;
+ tuple_count++;
+ }
+ else
+ {
+ dead_tuple_len += tuple->t_len;
+ dead_tuple_count++;
+ }
+
+ if (!BlockNumberIsValid(block) ||
+ block != BlockIdGetBlockNumber(&tuple->t_self.ip_blkid))
+ {
+ block = BlockIdGetBlockNumber(&tuple->t_self.ip_blkid);
+ buffer = ReadBuffer(rel, block);
+ free_space += PageGetFreeSpace((Page)BufferGetPage(buffer));
+ ReleaseBuffer(buffer);
+ }
+ }
+ heap_endscan(scan);
+ heap_close(rel, NoLock);
+
+ table_len = (double)nblocks*BLCKSZ;
+
+ if (nblocks == 0)
+ {
+ tuple_percent = 0.0;
+ dead_tuple_percent = 0.0;
+ free_percent = 0.0;
+ }
+ else
+ {
+ tuple_percent = (double)tuple_len*100.0/table_len;
+ dead_tuple_percent = (double)dead_tuple_len*100.0/table_len;
+ free_percent = (double)free_space*100.0/table_len;
+ }
+
+ elog(NOTICE,"physical length: %.2fMB live tuples: %u (%.2fMB, %.2f%%) dead tuples: %u (%.2fMB, %.2f%%) free/reusable space: %.2fMB (%.2f%%) overhead: %.2f%%",
+
+ table_len/1024/1024, /* phsical length in MB */
+
+ tuple_count, /* number of live tuples */
+ (double)tuple_len/1024/1024, /* live tuples in MB */
+ tuple_percent, /* live tuples in % */
+
+ dead_tuple_count, /* number of dead tuples */
+ (double)dead_tuple_len/1024/1024, /* dead tuples in MB */
+ dead_tuple_percent, /* dead tuples in % */
+
+ (double)free_space/1024/1024, /* free/available space in MB */
+
+ free_percent, /* free/available space in % */
+
+ /* overhead in % */
+ (nblocks == 0)?0.0: 100.0
+ - tuple_percent
+ - dead_tuple_percent
+ - free_percent);
+
+ PG_RETURN_FLOAT8(dead_tuple_percent);
+}
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