$Id: README.pgstattuple.euc_jp,v 1.4 2002/09/04 02:54:59 ishii Exp $

pgstattuple README		2002/08/22 ÀаæãÉ×

1. pgstattuple¤È¤Ï

   pgstattuple¤Ï¡¤UPDATE¤äDELETE¤Çºî¤é¤ì¤¿¥Æ¡¼¥Ö¥ë¤Î¥´¥ßÎΰè¤ÎÂ礭¤µ¤ò¡¤
   ¥Æ¡¼¥Ö¥ë¼«ÂΤÎʪÍýŪ¤ÊÂ礭¤µ¤ËÂФ¹¤ë¥Ñ¡¼¥»¥ó¥Æ¡¼¥¸¤ÇÊֵѤ·¤Þ¤¹¡¥¤Ä
   ¤Þ¤ê¡¤ÊÖµÑÃͤ¬Â礭¤±¤ì¤Ð¡¤¤½¤ì¤À¤±¥´¥ß¤â¿¤¤¤Î¤Ç¡¤vacuum¤ò¤«¤±¤ëɬ
   Íפ¬¤¢¤ë¤È¤¤¤¦È½ÃǤνõ¤±¤Ë¤Ê¤ë¤ï¤±¤Ç¤¹¡¥¤³¤ì°Ê³°¤Ë¤â¤¤¤í¤¤¤í¤Ê¾ðÊó
   ¤¬ÊÖ¤ê¤Þ¤¹¡¥

test=# \x
Expanded display is on.
test=# select * from pgstattuple('pg_proc');
-[ RECORD 1 ]------+-------
table_len          | 458752
tuple_count        | 1470
tuple_len          | 438896
tuple_percent      | 95.67
dead_tuple_count   | 11
dead_tuple_len     | 3157
dead_tuple_percent | 0.69
free_space         | 8932
free_percent       | 1.95

³Æ¹àÌܤÎÀâÌÀ¤Ç¤¹¡¥

table_len		-- ¥Æ¡¼¥Ö¥ë¤ÎʪÍýŪ¤ÊÂ礭¤µ(¥Ð¥¤¥È)
tuple_count		-- ¥¿¥×¥ë¿ô
tuple_len		-- ¥¿¥×¥ëĹ¤Î¹ç·×(¥Ð¥¤¥È)
tuple_percent		-- ¥¿¥×¥ë¤Î³ä¹ç¡¥table_len¤ËÂФ¹¤ëtuple_len¤ÎÈæΨ¡¥
dead_tuple_len		-- ¥Ç¥Ã¥É¥¿¥×¥ë¿ô
dead_tuple_percent	-- ¥Ç¥Ã¥É¥¿¥×¥ë¤Î³ä¹ç¡¥table_len¤ËÂФ¹¤ëtuple_len¤ÎÈæΨ¡¥
free_space		-- ºÆÍøÍѲÄǽ¤ÊÎΰè(¥Ð¥¤¥È)
free_percent		-- ºÆÍøÍѲÄǽ¤ÊÎΰ补table_len¤ËÂФ¹¤ëfree_space¤ÎÈæΨ¡¥

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¡¥

   CREATE OR REPLACE FUNCTION pgstattuple(text) RETURNS pgstattuple_type
     AS 'MODULE_PATHNAME', 'pgstattuple'
     LANGUAGE 'c' WITH (isstrict);

   Âè°ì°ú¿ô: ¥Æ¡¼¥Ö¥ë̾

   ´Ø¿ô¤ÎÌá¤ê¤Ïpgstattuple_type·¿¤Ç¤¹¡¥

   pgstattuple¤Ï¥Æ¡¼¥Ö¥ë¤ËAccessShareLock¤·¤«¤«¤±¤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¡¥

   pgstattuple¤¬¥¿¥×¥ë¤ò¡Ö¥´¥ß¡×¤ÈȽÃǤ¹¤ë´ð½à¤Ï¡¤
   HeapTupleSatisfiesNow()¤¬µ¶¤òÊÖ¤·¤¿¤È¤­¤Ç¤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

   2002/09/04

	SRFÊѹ¹¤Ëȼ¤¤¡¤Tom Lane	¤¬½¤Àµ¥¤¥ó¥¿¡¼¥Õ¥§¥¤¥¹¤Î½¤Àµ¤ò¹Ô¤Ã¤¿¡¥
	¤½¤Î¤³¤È¤ò¤³¤ÎREADME¤Ë¤âÈ¿±Ç¡¥

   2002/08/23

	SRF(Set Returning Function)¤ò»È¤Ã¤Æ7.3ÍѤ˽ñ¤­´¹¤¨¡¥

   2001/12/20 Tom Lane¤Ë¤è¤ë½¤Àµ

   	Fix pgstattuple to acquire a read lock on the target table.  This
	prevents embarassments such as having the table dropped or truncated
	partway through the scan.  Also, fix free space calculation to include
	pages that currently contain no tuples.

   2001/10/01 PostgreSQL 7.2 ÍÑcontrib module¤ËÅÐÏ¿

   2001/08/30 pgstattuple ¥Ð¡¼¥¸¥ç¥ó 0.1¥ê¥ê¡¼¥¹