Re: [SQL] weird(to me) request

[Larry Rosenman]

--On Thursday, September 25, 2003 20:59:25 +0200 Adam Wieckowski <[EMAIL PROTECTED]> wrote:

U�ytkownik Larry Rosenman napisa�:

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 ?

I'm actually looking to enforce the fact that if master_acct_num is entered, it points
to a valid acct_num.

LER

--
Larry Rosenman                     http://www.lerctr.org/~ler
Phone: +1 972-414-9812                 E-Mail: [EMAIL PROTECTED]
US Mail: 1905 Steamboat Springs Drive, Garland, TX 75044-6749

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