And/or

treeleaf20

Can you use these in the same query, for example:

"SELECT friend_id from mail where user_id='$userid' AND status='Unread' OR status='Read' ORDER BY message_id DESC LIMIT 0, 14"

If you can't how would you get this query to work?

Thanks

maxpup979

yes you can use those. I generally use parenthetical notation to make things a bit more clear though

treeleaf20

What is that?

maxpup979

"SELECT friend_id from mail where user_id='$userid' AND (status='Unread' OR status='Read') ORDER BY message_id DESC LIMIT 0, 14"

superwormy

Yes, in fact, MAKE SURE you use parenthesis... otherwise its confusing, perhaps not only to someone reading it, but possibly the parser could misinterpret it as well and give you some funky results.

TheDefender

It's the same principal as in math...
Consider the following math examples:

1 + 2 5 - 1 = 10
(1 + 2) (5 - 1) = 12
1 + 2 * (5 - 1) = 9

The numbers in the equations are all the same, but when you add in parenthesis, the eqution's evaluations drastically change... It's the same concept when you start dealing with boolean expressions.