Re: [GENERAL] B-tree + sorting + unique constraint

2010-12-29 Thread bricklen
On Wed, Dec 29, 2010 at 5:04 PM, Jeff Davis wrote: > On Wed, 2010-12-29 at 16:39 -0800, bricklen wrote: >> -- works: >> create unique index t_uidx on t (x desc nulls last,y desc nulls last, z asc); >> drop index t_uidx; > > ... > >> -- creating the unique constraint with sorting fails: >> alter ta

Re: [GENERAL] B-tree + sorting + unique constraint

2010-12-29 Thread Jeff Davis
On Wed, 2010-12-29 at 16:39 -0800, bricklen wrote: > -- works: > create unique index t_uidx on t (x desc nulls last,y desc nulls last, z asc); > drop index t_uidx; ... > -- creating the unique constraint with sorting fails: > alter table t add constraint t_xyz_uc unique (x desc nulls last,y desc

[GENERAL] B-tree + sorting + unique constraint

2010-12-29 Thread bricklen
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: