Użytkownik Larry Rosenman napisał:
> I have the following rows (in addition to others):
>
> acct_num text,
> master_acct_num text,
>
>
> These are in the same table.
>
> What I want to enforce is that if the master_acct_num field is NOT
> NULL (it can be NULL, and
> that's fine), that the value appears in some row as acct_num.
> acct_num has a unique index on it, so that's fine.
>
> I'm not sure how to do this....
>
> Thanks!
>
> LER
>
>
select case when master_acct_num is null then acct_num else master_acct_num end from table;
did you mained somethink like this ?