Oracle Precompilers and Nulls

From: john <coghawks_at_mentor.cc.purdue.edu>
Date: 3 Sep 92 23:19:42 GMT
Message-ID: <Bu0zGv.941_at_mentor.cc.purdue.edu>

I recently happened into a problem using Pro-C with embedded SQL with Nulls and comparison differences between = and IS (NOT) NULL. It was when I had built a cursor which selected into a host variable, which was then used as part of a selection criteria on the next SQL statement. What occured was that when using the where clause for ex. WHERE EMPD.DESCRIPT = :host_emp, if either value was null then this never would return true or if they both were null it still wouldn't be true. So either I had to have 2 versions and check explicitly if and when things were NULL before I use them in a WHERE clause, or set them to a default value. Which in oracle is syntactily supported, but not implemented when declaring a table. Another problem with setting things to a default value is then building indexes etc.. those values are all grouped. I am new at this and am looking forward to any replies.

Thank you
John Hawkins.

---

I disclaim !! I disclaim!! Received on Fri Sep 04 1992 - 01:19:42 CEST