From 6f3a13ff058f15d565a30c16c0c2cb14cc994e42 Mon Sep 17 00:00:00 2001
From: Simon Riggs <simon@2ndQuadrant.com>
Date: Mon, 6 Mar 2017 16:48:12 +0530
Subject: [PATCH] Enhance docs for ALTER TABLE lock levels of storage parms
As requested by Robert Haas
---
doc/src/sgml/ref/alter_table.sgml | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/doc/src/sgml/ref/alter_table.sgml b/doc/src/sgml/ref/alter_table.sgml
index da431f8369a..8b251f9e5d7 100644
--- a/doc/src/sgml/ref/alter_table.sgml
+++ b/doc/src/sgml/ref/alter_table.sgml
@@ -568,10 +568,17 @@ ALTER TABLE [ IF EXISTS ] <replaceable class="PARAMETER">name</replaceable>
That can be done with <link linkend="SQL-VACUUM">VACUUM
FULL</>, <xref linkend="SQL-CLUSTER"> or one of the forms
of <command>ALTER TABLE</> that forces a table rewrite.
+ For planner related parameters, changes will take effect from the next
+ time the table is locked so currently executing queries will not be
+ affected.
</para>
<para>
- Changing fillfactor and autovacuum storage parameters acquires a <literal>SHARE UPDATE EXCLUSIVE</literal> lock.
+ <literal>SHARE UPDATE EXCLUSIVE</literal> lock will be taken for
+ fillfactor and autovacuum storage parameters, as well as the
+ following planner related parameters:
+ effective_io_concurrency, parallel_workers, seq_page_cost
+ random_page_cost, n_distinct and n_distinct_inherited.
</para>
<note>
--
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