Re: Using union to avoid creating temp table

Bruno Wolff III <bruno@wolff.to> writes:
> What I ended up doing is building the input values into sepearte
> select statements unioned together. So if the input values were
> 'abc', 'def' and 'ghi', I would end up doing a select like:
> select add.id from (select 'abc' union select 'def' union select 'ghi') add (id)where not exists (select from role
whereadd.id = role.id)
 

Might be worth writing "union all" not "union".  This suppresses union's
check for duplicated rows, which you presumably don't need.
        regards, tom lane