Re: [GENERAL] Simulating an outer join

Bruce Momjian wrote:

> I am just writing the EXISTS section from my book.  I don't think it
> matters what fields are returned from an EXISTS subquery.  If I am
> wrong, someone please let me know.

Celko also writes (in his chapter on EXISTS in "SQL for Smarties"):

"In general the SELECT * option should perform better than the actual column.
It lets the query optimizer decide which column to use.  If a column has an
index on it, then simply seeing a pointer to the index is enough to determine
that something exists."

Obviously you're in a much better position than me to judge whether that's the
case in pgsql!  But it might be worth a test.

Julian Scarfe