Question

$query = mysql_query("UPDATE a SET fruit = '**apple**' WHERE id = '**1**' ");
$query2 = mysql_query("UPDATE a SET fruit = '**orange**' WHERE id = '**2**' ");
$query3 = mysql_query("UPDATE a SET fruit = '**peach**' WHERE id = '**3**' ");

有没有办法将其简化为一个查询？

Answer 1

我找到了以下解决方案：

INSERT into `table` (id,fruit)
    VALUES (1,'apple'), (2,'orange'), (3,'peach')
    ON DUPLICATE KEY UPDATE fruit = VALUES(fruit);

Id必须是唯一或主键。但不了解表现。

Answer 2

是的，您可以使用此查询执行此操作：

UPDATE a 
SET fruit = (CASE id WHEN 1 THEN 'apple'
                     WHEN 2 THEN 'orange'
                     WHEN 3 THEN 'peach'
             END)
WHERE id IN(1,2 ,3);

Answer 3

基于警告消息

'VALUES function' is deprecated and will be removed in a future release. Please use an alias (INSERT INTO ... VALUES (...) AS alias) and replace VALUES(col) in the ON DUPLICATE KEY UPDATE clause with alias.col instead

人们可能会考虑对Yaroslav的解决方案进行一些修改，例如：

INSERT into `table` (id,fruit)
VALUES (1,'apple'), (2,'orange'), (3,'peach') as tb
ON DUPLICATE KEY UPDATE fruit = tb.fruit;

它执行相同的操作，但是忽略警告消息。

Answer 4

在MySQL中使用IF（）函数可以实现为

POST

如何用一个查询批量更新mysql数据？

4 个答案: