Re: Composite types questions

On Mon, Jan 11, 2010 at 11:08 AM, Vincenzo Romano > SELECT * FROM master_tab
>  WHERE col1>='a date':timestamp AND col1<'another date'::timestamp
> AND col2=42 AND col3='the answer';

queries of this sort are optimally handled via row constructor for 8.2 onwards:

create index col231_idx on master_tab(col2, col3, col1);

select * from master_tab where (col2,col3,co1) >= (42, 'the answer',
a_date) and (col2,col3,co1) < (42, 'the answer', b_date);

one caveat: the planner is lousy in regards to estimating index
selectivity in these cases which can cause strange behaviors.

regarding constraint_exclusion, I don't think there are any
issues...you should test it to be sure.

merlin