diff --git a/doc/src/sgml/release-18.sgml b/doc/src/sgml/release-18.sgml index 66cdeb67961..33e9199d758 100644 --- a/doc/src/sgml/release-18.sgml +++ b/doc/src/sgml/release-18.sgml @@ -284,6 +284,23 @@ This optimization can be disabled using enable_distinct_reordering. + + + + +Ignore GROUP BY columns that are functionally dependent on other columns (Zhang Mingli, Jian He, David Rowley) +§ + + + +If a GROUP BY clause includes all columns of a unique index, as well as other columns of the same table, those other columns are redundant and can be dropped +from the grouping. This was already true for non-deferred primary keys. + + +