From: Alvaro Herrera <alvherre@alvh.no-ip.org>
Date: Fri, 5 Nov 2021 15:09:31 +0000 (-0300)
Subject: Document that ALTER TABLE .. TYPE removes statistics
X-Git-Url: http://git.postgresql.org/gitweb/static/developers.postgresql.org?a=commitdiff_plain;h=df80f9da5c6541e744eeb20eaca919c7fc189999;p=users%2Frhaas%2Fpostgres.git

Document that ALTER TABLE .. TYPE removes statistics

Co-authored-by: Nikolai Berkoff <nikolai.berkoff@pm.me>
Discussion: https://postgr.es/m/vCc8XnwDmlP4ZnHBQLIVxzD405BiYHVC9qZlhIF7IsfxK0gC9mZ4PUUOH0-3y6kv5p-87-3_ljqT1KvQVAnb8OoWhPU3kcqWn2ZpmxRBCQg=@pm.me
---

diff --git a/doc/src/sgml/ref/alter_table.sgml b/doc/src/sgml/ref/alter_table.sgml
index 81291577f8..2d639a66af 100644
--- a/doc/src/sgml/ref/alter_table.sgml
+++ b/doc/src/sgml/ref/alter_table.sgml
@@ -198,6 +198,12 @@ WITH ( MODULUS <replaceable class="parameter">numeric_literal</replaceable>, REM
       clause must be provided if there is no implicit or assignment
       cast from old to new type.
      </para>
+
+     <para>
+      When this form is used, the column's statistics are removed,
+      so running <link linkend="sql-analyze"><command>ANALYZE</command></link>
+      on the table afterwards is recommended.
+     </para>
     </listitem>
    </varlistentry>