On Wed, 25 Mar 2026 08:24:40 +0700
John Naylor <[email protected]> wrote:
> On Tue, Mar 24, 2026 at 6:34 PM Yugo Nagata <[email protected]> wrote:
> >
> > Hi,
> >
> > I've attached a patch to adjust the error message for CREATE STATISTICS
> > to account for expressions.
> >
> > Previously, when attempting to create extended statistics on a single
> > column,
> > the following error is raised.
> >
> > ERROR: extended statistics require at least 2 columns
> >
> > However, this message assumed only columns. In reality, an expression on a
> > single column is also allowed, so two columns are not necessarily required.
> > Thgis patch updates the message to:
> >
> > ERROR: extended statistics require at least 2 columns or an expression
>
> I'm ambivalent about this. Instead of trying to document all the
> possible valid possibilities (which may get out of date again), maybe
> we can say that it's not allowed on a single column?
Thank you for the suggestion. I agree that this is a simpler approach,
so I've attached a revised patch.
Regards,
Yugo Nagata
--
Yugo Nagata <[email protected]>
diff --git a/src/backend/commands/statscmds.c b/src/backend/commands/statscmds.c
index c1da79f36ba..f5a089903d8 100644
--- a/src/backend/commands/statscmds.c
+++ b/src/backend/commands/statscmds.c
@@ -437,7 +437,7 @@ CreateStatistics(CreateStatsStmt *stmt, bool check_rights)
if ((numcols < 2) && (list_length(stxexprs) != 1))
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
- errmsg("extended statistics require at least 2 columns")));
+ errmsg("extended statistics are not supported on a single column")));
/*
* Sort the attnums, which makes detecting duplicates somewhat easier, and
