MySQL множественного обновление с 2-х, где

Question

я стараюсь, чтобы получить несколько запросов обновления Mysql в одном запросе, у меня есть 3 тестов запросов

UPDATE `stock` SET `date_time_out`='2016-12-05 13:47:05' WHERE `weighting_id` = '80' AND `date_time_out` = '0000-00-00 00:00:00' 
UPDATE `stock` SET `date_time_out`='2016-12-05 13:46:05' WHERE `weighting_id` = '79' AND `date_time_out` = '0000-00-00 00:00:00' 
UPDATE `stock` SET `date_time_out`='2016-12-05 13:45:05' WHERE `weighting_id` = '78' AND `date_time_out` = '0000-00-00 00:00:00' 

Я создал запрос следующего запроса, но doesn'twork

UPDATE `stock` 
SET value = CASE 
WHEN `weighting_id` = '80' AND `date_time_out` = '0000-00-00 00:00:00' THEN '2016-12-05 13:47:05' 
WHEN `weighting_id` = '79' AND `date_time_out` = '0000-00-00 00:00:00' THEN '2016-12-05 13:46:05' 
WHEN `weighting_id` = '78' AND `date_time_out` = '0000-00-00 00:00:00' THEN '2016-12-05 13:45:05' 
ELSE VALUE 
END 

Answer 1

Я нашел ответ следующий код работает OK:

UPDATE `stock` 
SET `date_time_out` = CASE 
WHEN `weighting_id` = '70' AND `date_time_out` = '0000-00-00 00:00:00' THEN '2016-12-05 13:47:05' 
WHEN `weighting_id` = '71' AND `date_time_out` = '0000-00-00 00:00:00' THEN '2016-12-05 13:48:05' 
WHEN `weighting_id` = '72' AND `date_time_out` = '0000-00-00 00:00:00' THEN '2016-12-05 13:48:05' 
WHEN `weighting_id` = '73' AND `date_time_out` = '0000-00-00 00:00:00' THEN '2016-12-05 13:48:05' 
WHEN `weighting_id` = '74' AND `date_time_out` = '0000-00-00 00:00:00' THEN '2016-12-05 13:48:05' 
WHEN `weighting_id` = '75' AND `date_time_out` = '0000-00-00 00:00:00' THEN '2016-12-05 13:48:05' 
ELSE `date_time_out` 
END 

WHERE `weighting_id` IN ('70', '71', '72', '73', '74', '75') AND `date_time_out` IN ('0000-00-00 00:00:00') 

Код около 100X-150X быстрее, чем 5 отдельных запросов на обновление.

Answer 2

вы можете попробовать так:

UPDATE `stock` 
    SET value = (CASE 
    WHEN `weighting_id` = '80' THEN '2016-12-05 13:47:05' 
    WHEN `weighting_id` = '79' THEN '2016-12-05 13:46:05' 
    WHEN `weighting_id` = '78' THEN '2016-12-05 13:45:05'   
    END 
    ) WHERE weighting_id in ('80','79','78') AND `date_time_out` = '0000-00-00 00:00:00'