Answers:
UPDATE mytable SET
fruit = CASE WHEN id=1 THEN 'orange' ELSE 'strawberry' END,
drink = CASE WHEN id=1 THEN 'water' ELSE 'wine' END,
food = CASE WHEN id=1 THEN 'pizza' ELSE 'fish' END
WHERE id IN (1,2);
就个人而言,使用CASE WHEN THEN END
看起来笨拙。
您可以使用IF函数对此进行编码。
UPDATE mytable SET
fruit = IF(id=1,'orange','strawberry'),
drink = IF(id=1,'water','wine'),
food = IF(id=1,'pizza','fish')
WHERE id IN (1,2);
试试看 !!!
CAVEAT:CASE WHEN THEN END
仅在处理多个值(大于2)时方便
INSERT ... ON DUPLICATE KEY UPDATE
如果要更新两个以上的行,则需要编写非常复杂的条件。在这种情况下,您可以使用INSERT ... ON DUPLICATE KEY UPDATE
方法。
INSERT into `mytable` (id, fruit, drink, food)
VALUES
(1, 'orange', 'water', 'pizza'),
(2, 'strawberry', 'wine', 'fish'),
(3, 'peach', 'jiuce', 'cake')
ON DUPLICATE KEY UPDATE
fruit = VALUES(fruit),
drink = VALUES(drink),
food = VALUES(food);