Simple SQL question
 

I am using Php and MySQL. I'm trying to do a query that searches for entires that have a NULL value in the used field.

$query = "SELECT * FROM codes WHERE used = NULL";


Several entries do have a null value, however I am not returning anything with my query. Is there a specific syntax for search for = NULL or != NULL fields?

Would it just be is NULL and not NULL? something like that?

Thanks,
Karl

try 'is' instead of '='