CREATE TRIGGER leave_trigger
 AFTER INSERT ON leaveapplication
 FOR EACH ROW
 IF employeemaster.empcode='".$empcode."' THEN
 UPDATE employeemaster SET '".$leave_type=$leave_type."'-$numberofleave //I am facing problem here
 END IF;

UPDATE employeemaster SET '".$fieldName."=".$leave_type."'-$numberofleave

UPDATE
    employeemaster
        SET leave_type=leave_type-".$numberofleave."
        where empcode='".$empcode."'

CREATE TRIGGER leave_trigger
    AFTER INSERT ON leaveapplication
    FOR EACH ROW
        UPDATE employeemaster SET leave_type=leave_type-NEW.numberofleave where empCode=NEW.empCode
    END;