如果在MySQL中找到第二行，则将其删除

Question

如果商人有2行，我试图在MySql中删除一行。删除哪一行都没有关系。

当我跑步时：

SELECT * FROM products.merchant_configs WHERE `configKey` = 'CHECK_BALANCE_SUBJECT'
AND merchantId = 6;

我知道：

现在，我尝试删除以下行之一：

DELETE FROM products.merchant_configs
WHERE id = (
    SELECT id FROM products.merchant_configs WHERE `configKey` = 'CHECK_BALANCE_SUBJECT'
    AND merchantId = 6
    LIMIT 2 OFFSET 1
);

我收到错误：

Error Code: 1093. You can't specify target table 'merchant_configs' for update in FROM clause

这是怎么回事？

Answer 1

将查询嵌套到另一个select语句中

DELETE FROM products.merchant_configs
WHERE id = (SELECT t.id FROM (
    SELECT id FROM products.merchant_configs WHERE `configKey` = 'CHECK_BALANCE_SUBJECT'
    AND merchantId = 6
    LIMIT 2 OFFSET 1
) t);

请参见demo。