At 11:03 AM 24-02-01 -0500, you wrote:

>Helen,
>
>Unfortunately your assertion is not true, a UNION can return a set
>containing any number of rows including 0 and 1.

Quite true - but it's not a singleton select, because it potentially returns multiple rows.
Just the same as
select * from aTable where account_type='FREE' is not a singleton select, even if it returns 1 or 0 rows.

Helen

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