SQL Question :

Posted in 1997

Belakimem — 2 Oct 1997 23:09:52 GMT — source: Informix-list mailing list archive (1991-1998)

I have been told that SELECT UNIQUE 1, is more efficient than SELECT COUNT(*), in order to find the existence of rows (not needing the count). My experiments have shown that without a where clause, unique 1 is very slow for large tables, but with a where clause they are the same. Any thoughts? Potential repsonders, please also reply be email, thank you!