Question

I have a query with NOT IN. I’ve heard MySQL doesn’t support NOT IN, but I can’t figure how to rewrite it.

My query is:

SELECT * FROM quests
  WHERE id NOT IN ('" .$quest_completed. "') 
  AND location=" .$location_id. "
  AND (follows=0 OR follows IN ('" .$quest_completed. "')) 
  ORDER BY title

eg:

SELECT * FROM quests 
WHERE id NOT IN (6,21) AND 
  location=8 AND 
  (follows=0 OR follows IN (6,21))
ORDER BY title

Row id 6 is being returned in that when I specified WHERE id NOT IN 6

Answer 1

It looks like, because of your use of apostrophes around the $quest_completed variable, the query that’s actually being executed is likely to be NOT IN ('6,21'), rather than NOT IN (6,21) (which I think is what you want?).

The difference is that the first version returns records where id is not equal to the string '6,21', whereas the second version returns records where id is neither the number 6 nor the number 21.