Question

I recently found that a query would not work on some of my records if the values where null. Apparently in SQL, null cannot be compared to anything – even null.

UPDATE company SET views = IF(views, views + 1, 1),
trendingViews = IF(viewed != '2012-05-21 00:00:00', 1, trendingViews + 1),
viewed = IF(viewed != '2012-05-21 00:00:00', '2012-05-21 00:00:00', viewed)
WHERE id = '3024'

How can I change this query to conditionally check for the values provided and null?

Answer 1

use COALESCE:

UPDATE company 
SET views = COALESCE(views, 0) + 1,
    trendingViews = IF(viewed != '2012-05-21 00:00:00', 1, trendingViews + 1),
    viewed = IF(viewed != '2012-05-21 00:00:00', '2012-05-21 00:00:00', viewed)
WHERE id = '3024'