Question

I am trying to update using if which is shown below
you will get idea what i want to do

UPDATE messages SET IF(u1= :username,u1_delete=1,u2_delete=1) 
WHERE thread_id= :thread_id

i want update u1_delete when u1 is username otherwise it will update u2_delete field

Answer 1

You can use the case statement as follows:

UPDATE messages 
SET 
    u1_delete = CASE WHEN u1= :username THEN 1 ELSE u1_delete END,
    u2_delete = CASE WHEN u1= :username THEN u2_delete ELSE 1 END,
WHERE 
    thread_id= :thread_id