Question

lets say I have this query:

mysql_query("UPDATE results_tb SET num_unmarked - 1 WHERE user_id = $student AND test_id = $test AND item_id = $item")

is there a way within mysql to essentially do an IF statement which checks that if num_unmarked will be 0 after it is decremented. if it is 0 I want to update another field basically.

kinda like IF( num_unmarked == 0 ) SET is_final = ‘YES’…

just curious if there are ways to do it rather than querying and checking the value if you see where I am coming from. I am rather inexperienced with MySQL.

many thanks,

Answer 1

Sure you can

$sql="
    UPDATE results_tb
       SET num_unmarked=num_unmarked-1,
           is_final=IF( num_unmarked-1=0,'yes',is_final )
       WHERE
            user_id = {$student} 
         AND 
            test_id = {$test} 
         AND 
            item_id = {$item} 
";
mysql_query($sql)...
...