Mysql or/and precedence?

Question

I am wondering how or/and works?

For example if I want to get all rows where display = 1

I can just do WHERE tablename.display = 1

and i

Answer 1

in all SQL servers, AND takes precedence over OR, so just remember to put brackets around your ORs:

select * from tablename 
where (display = 1 or display = 2)
 and (content like "%hello world%" 
      or tags like "%hello world%" 
      or title = "%hello world%")

btw (display = 1 or display = 2) is equivalent to display in (1, 2).