Hi, I have a follow-up question to my earlier question[1] about how sorting works in an index.
Does creating a UNIQUE constraint not allow the aforementioned sorting capability? eg. create table t (x int, y int, z int); insert into t values (1,1,1),(2,2,2),(3,3,3),(1,2,3),(15,23,21); -- works: create unique index t_uidx on t (x desc nulls last,y desc nulls last, z asc); drop index t_uidx; -- works: alter table t add constraint t_uc unique (x,y,z); alter table t drop constraint t_uc; -- creating the unique constraint with sorting fails: alter table t add constraint t_xyz_uc unique (x desc nulls last,y desc nulls last, z asc); ERROR: syntax error at or near "desc" LINE 1: alter table t add constraint t_uidx unique (x desc nulls las... [1] - http://archives.postgresql.org/pgsql-general/2010-12/msg00959.php -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
