Document that ALTER TABLE .. TYPE removes statistics

alvherre · nikolai-b · alvherre · commit df80f9da5c65 · 2021-11-05T12:09:31.000-03:00
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
@@ -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>
 
