update_batch is not working !

Hi there ,

I am facing a problem with update batch function

 it is showing the following query which is error !!

i am using the 3.1.2

Code:

UPDATE `sd_settings` SET

`s_setting` = CASE
WHEN `s_setting` =  THEN 'default_lang'
WHEN `s_setting` =  THEN 'reg_mode'
WHEN `s_setting` =  THEN 'site_offline'
WHEN `s_setting` =  THEN 'refresh'
WHEN `s_setting` =  THEN 'login_token'

ELSE `s_setting` END,

`s_value` = CASE
WHEN `s_setting` =  THEN 'ar'
WHEN `s_setting` =  THEN 'all'
WHEN `s_setting` =  THEN '0'
WHEN `s_setting` =  THEN '66'
WHEN `s_setting` =  THEN 'r34zn16'

ELSE `s_value` END
WHERE `s_setting` IN(,,,,)

can anyone help please ?