This is probably a stupid question, but ...
I'd like to be able to take an existing query and modify it to return a
single row if that's what the base query returns, and 0 rows if the
base query returns multiple rows. Similarly, I'd like to also modify
it to return multiple rows if that's what the base query returns, and 0
rows if the base query return a single row.
What's a good way to do this?
Thanks,
Kevin Murphy