title: Mysql case not working
body: <pre><code>SELECT 
       SQL_CALC_FOUND_ROWS a.* , 
       zn.`name` AS zone_name, 
       c.`name` AS carrier_name, 
       CASE type 
         WHEN type=1 THEN 'General day' 
         ELSE 'Special date' END AS type_changed, 
      CASE week_day 
         WHEN week_day = -1 THEN 'notset' 
         WHEN week_day = 1 THEN 'monday' 
         WHEN week_day = 2 THEN 'tuesday' 
         WHEN week_day = 3 THEN 'wednesday' 
         WHEN week_day = 4 THEN 'thursday' 
         WHEN week_day = 5 THEN 'friday' 
         WHEN week_day = 6 THEN 'saturday' 
         WHEN week_day = 7 THEN 'sunday' END AS week_day_mod , 
     IF(date = '0001-01-01 00:00:0', '--', DATE(date)) AS date_mod,            IF(is_working_day = 1 ,'working day', 'day off') AS is_working_day_mod 
    FROM `ps_deliverytime_table` a 
    LEFT JOIN ps_zone AS zn ON(a.`id_zone` = zn.`id_zone`) 
    LEFT JOIN ps_carrier AS c ON(a.`id_carrier` = c.`id_carrier`) 
    WHERE 1 ORDER BY a.`id_time_table` ASC LIMIT 0,50
  </code></pre>
  
  <p>When week day is equal 1 it works fine but in other case it do not working</p>