On 18 Apr 2002 at 8:14, maria_ana_ph wrote:

>The problem is, if the second field (FIELD2) is NULL, the third field
>(CAST (A.FIELD2 AS FLOAT) - CAST (B.FIELD2 AS FLOAT)) would return
>NULL where it should the value of FIELD2.
>
>Do you know how would i go about this?

Alter table B alter column FIELD2 type float default 0 not null;
update B set FIELD2=0 where FIELD2 is null;

SY, Dimitry Sibiryakov.