Question

i have some trouble with my query:

SELECT 
  * 
FROM 
  att 
WHERE 
  uid = "f6c507fe-8928-4780-8b54-819611435755" 
AND 
  item_position <> '99' 
AND 
  category IN('CAT1','CAT2');

The result is nothing. When I remove “item_position <> ’99’ AND”, some items where displayed. I think the problem is the UNLIKE with IN… There a some rows with category “CAT1” and item_position “99”. These rows should not be displayed.

Greetings!

Answer 1

Try:

SELECT 
  * 
FROM 
  att 
WHERE 
  uid = "f6c507fe-8928-4780-8b54-819611435755" 
AND 
  (item_position <> '99' OR item_position IS NULL)
AND 
  category IN('CAT1','CAT2');

You mentioned that some rows are NULL. Annoyingly NULL values and <> tend to hate each other in logic, I recall.