On 2021-Oct-19, Michael Paquier wrote: > On Mon, Oct 18, 2021 at 05:15:59PM -0300, Euler Taveira wrote: > > I agree that it might surprise an user and it would be good to document it. > > However, it does not belong to the description. I would add it to the Notes > > section at the end of the ALTER TABLE page. > > No objections to the suggested addition and the location of the > addition (paragraph of SET DATA TYPE rather than "Notes"), but I think > that the phrasing could be better: > "The column's statistics are removed, hence a follow-up ANALYZE is > suited to update the statistics to the new column type."
Dunno, putting it in the middle of the existing paragraph looks odd to me. I would put it in a separate one instead, as in the attached. -- Álvaro Herrera PostgreSQL Developer — https://www.EnterpriseDB.com/
diff --git a/doc/src/sgml/ref/alter_table.sgml b/doc/src/sgml/ref/alter_table.sgml index 81291577f8..86fc15c8b3 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 <command>ANALYZE</command> on the table afterwards + is recommended. + </para> </listitem> </varlistentry>