Home Forums Article Discussions Article Discussions by Author Discuss content posted by Todd Carrier Know your UNION(s), NULL(s), COUNT(s) ? RE: Know your UNION(s), NULL(s), COUNT(s) ?

  • June 4, 2008 at 2:27 am

    #824038

    Before answering I was wondering if missing ALL on final union was intentional or a typo.

    Count(*) counts all rows, Count([ALL] column) counts rows where column is not null, so it doesn't matter whether final union is just "union" or "union all".

    Fun question anyway. 🙂