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 8:03 am

    #824193

    Ya, great question.

    I didn't realize the subtle different between Count(*), Count(1) and Count(expression)

    Count(*) - Includes Nulls

    Count(1) - Includes Nulls

    Count(expression) - Does not include nulls ie Count(ColumnName)