On Oct 30, 2006, at 3:27 PM, Jay Blanchard wrote:
[snip] I am trying to find records where the value of a filed is NULL. I know that there are records that have null values but the result is always an empty set. eg: select test_id from tests where test_id=NULL always returns an empty set when there are in fact records that have a null value for test_id. Is there some trick to finding null valued records in MySQL? This same sql has always worked on any other dbms I have used. [/snip] Of course this will return an empty set because you have only selected the test_id, try this; SELECT * FROM tests WHERE test_id IS NULL
Yes, that works, but I was also trying SELECT * instead of just the key field (just a typo in the example). The problem was in the equal sign versus the 'IS' operator. Any reason why MySQL does not honor <field>=NULL? Seems kind of odd.
alan -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
