Question

I have 2 tables (TABLE1 & TABLE2). I would like to execute the below query:

UPDATE TABLE1 a,TABLE1 b
SET a.desg=CASE WHEN b.attribute_id=74 THEN b.value ELSE a.desc END
WHERE a.entity_id=b.entity_id;

But i have some rows in TABLE1 with entity_id as NULLs.
These are not being considered while evaluating WHERE a.entity_id=b.entity_id;

I want even the NULLs to be considered for this WHERE clause.

How can i do this? Thanks in advance.

Answer 1

Try to use something like

WHERE IFNULL(a.entity_id, 0) = IFNULL(b.entity_id, 0);