Re: deciding on one of multiple results returned

If a query returns, say the following results:

id   value
0      a
0      b
0      c
1      a
1      b



How do I just choose a preferred element say value 'a' over any other elements returned, that is the value returned is from a subquery to a larger query?

Thanks.

ORDER BY

(with a LIMIT depending on circumstances)

David J.