Q. I've done the following:
CREATE TABLE T1(A Int, B Int);
CREATE UNIQUE INDEX I1 ON T1 (A, B);
INSERT INTO T1 VALUES (1, NULL);
This results in the following error:
Statement failed, SQLCODE = -803
attempt to store duplicate value (visible to active transactions) in unique index "T1"
-null segment of UNIQUE KEY
What is the cause?
A. Unique indexes do not allow NULLs even if they have multiple fields. If you require NULL data in a multifield index, there are two approaches you can take to solve this problem:
Last Modified: 18-JAN-01