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Diffstat (limited to 'doc/src/sgml/ref/explain.sgml')
| -rw-r--r-- | doc/src/sgml/ref/explain.sgml | 18 |
1 files changed, 17 insertions, 1 deletions
diff --git a/doc/src/sgml/ref/explain.sgml b/doc/src/sgml/ref/explain.sgml index 166bbbf4c32..8173ac0b1f9 100644 --- a/doc/src/sgml/ref/explain.sgml +++ b/doc/src/sgml/ref/explain.sgml @@ -10,7 +10,7 @@ EXPLAIN EXPLAIN </REFNAME> <REFPURPOSE> -Shows statement execution details. +Shows statement execution details </REFPURPOSE> <REFSYNOPSISDIV> @@ -64,11 +64,19 @@ Outputs <VARLISTENTRY> <TERM> NOTICE: QUERY PLAN: +<replaceable>plan</replaceable> </TERM> <LISTITEM> <PARA> Explicit query plan from the <productname>Postgres</productname> backend. +<VARIABLELIST> +<VARLISTENTRY> +<TERM> +<replaceable>status</replaceable> +</TERM> +<LISTITEM> +<PARA> <VARLISTENTRY> <TERM> EXPLAIN @@ -78,6 +86,7 @@ EXPLAIN Flag sent after query plan is shown. </VARIABLELIST> +</VARIABLELIST> </REFSECT2> </REFSYNOPSISDIV> @@ -102,6 +111,13 @@ Description Notes </TITLE> <PARA> +There is only sparse documentation on the optimizer's use of cost +information in <productname>Postgres</productname>. +General information on cost estimation for query optimization +can be found in database textbooks. +Refer to the <citetitle>Programmer's Guide</citetitle> +in the chapters on indexes and the genetic query optimizer for +more information. </REFSECT2> |