On Thu, Jun 28, 2018 at 5:28 AM, Yugo Nagata <nag...@sraoss.co.jp> wrote: > According to the error message, it is not allowed to alter statistics on > included column because this is "non-expression column". > > postgres=# create table test (i int, d int); > CREATE TABLE > postgres=# create index idx on test(i) include (d); > CREATE INDEX > postgres=# alter index idx alter column 2 set statistics 10; > ERROR: cannot alter statistics on non-expression column "d" of index "idx" > HINT: Alter statistics on table column instead. > > However, I think this should be forbidded in that this is not a key column > but a included column. Even if we decide to support expressions in included > columns in future, it is meaningless to do this because any statistics on > included column is never used by the planner. > > Attached is the patch to fix the error message. In this fix, column number > is checked first. After applying this, the message is changed as below; > > postgres=# alter index idx alter column 2 set statistics 10; > ERROR: cannot alter statistics on included column "d" of index "idx"
I think you should add an open item for this. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company
