From: Tom Lane <tgl@sss.pgh.pa.us> Date: Sat, 15 Jan 2005 07:53:04 +0000 (+0000) Subject: Minor improvements in descriptions of recent changes. X-Git-Tag: REL8_0_0~23 X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=0e3afb327711104fb17be42628c0ca3ce304c197;p=postgresql Minor improvements in descriptions of recent changes. --- diff --git a/doc/src/sgml/release.sgml b/doc/src/sgml/release.sgml index 0be3671931..7d191056a7 100644 --- a/doc/src/sgml/release.sgml +++ b/doc/src/sgml/release.sgml @@ -1,5 +1,5 @@ <!-- -$PostgreSQL: pgsql/doc/src/sgml/release.sgml,v 1.319 2005/01/15 05:59:44 momjian Exp $ +$PostgreSQL: pgsql/doc/src/sgml/release.sgml,v 1.320 2005/01/15 07:53:04 tgl Exp $ --> <appendix id="release"> @@ -648,14 +648,18 @@ $PostgreSQL: pgsql/doc/src/sgml/release.sgml,v 1.319 2005/01/15 05:59:44 momjian <listitem> <para> - Improve optimizer row estimates for non-<command>VACUUM</command>ed - tables (Tom) + Improve optimizer rowcount estimates (Tom) </para> <para> - The system now uses the number of blocks in the table to estimate the - number of rows in the table if it has never been - <command>VACUUM</command>ed or <command>ANALYZE</command>d. - Previously a fixed value was used in such cases. + Formerly the planner estimated table sizes using the values seen + by the last <command>VACUUM</command> or <command>ANALYZE</command>, + both as to physical table size (number of pages) and number of rows. + Now, the physical table size is obtained directly from the kernel, + and the number of rows is estimated by multiplying the table size + by the row density (rows per page) seen by the last + <command>VACUUM</command> or <command>ANALYZE</command>. This should + produce more reliable estimates in cases where the table size has + changed significantly since the last housekeeping command. </para> </listitem> @@ -1744,10 +1748,11 @@ $PostgreSQL: pgsql/doc/src/sgml/release.sgml,v 1.319 2005/01/15 05:59:44 momjian <listitem> <para> - Allow PL/pgSQL to understand <command>ELSEIF</> (Neil) + Accept <command>ELSEIF</> in PL/pgSQL (Neil) </para> <para> - Previously PL/pgSQL only understood <command>ELSIF</>. + Previously PL/pgSQL only allowed <command>ELSIF</>, but many people + are accustomed to spelling this keyword <command>ELSEIF</>. </para> </listitem>