Question

How can I reset a flag to false, in just one statement, only if it is true & if its already true just ignore it? I would also like to do opposite to this. Here is a situation, I want to ban a user only if he/she is active, if he/she is already banned I dont want to do anything. I also want to unban the user if he/she is banned but don’t want to do anything if he/she is already active. Can this be clubbed in just one statement?

Answer 1

No, this has to be two statements (one to set a user to banned, the other to set the user to unbanned), but it does not have to be complicated.

Assuming that you have a flag “$banned”, you would simply set that to true if you wanted the user banned, and false if the user is not supposed to be banned. It does not matter what that user was before — simply continue on your way, everything should work itself out nicely.

With SQL, you might have a BANNED column. UPDATE won’t care if the value is staying the same, so just run the update:

-- this will set BANNED to false. Use 1 to set it to true
UPDATE my_table SET BANNED = 0 WHERE ID = <your id>

All of that said, you may want to force the user to log out and log back in after they have been banned, but that is a matter for another question.