结合选择和更新mysql查询以进行计数

Question

SELECT `EAN`, COUNT(*) FROM `sales` WHERE `EAN` = '5052931107087';

UPDATE `monitoring` SET `times` = COUNT(*) WHERE `EAN` = '5052931107087';

I have these two mysql queries and I want to combine them in to one query. The purpose is to count the number of times an EAN code appears in the sales table and then in the monitoring table update the times count to the count from the first query.

The first query works fine and the second works fine if you replace COUNT(*) with a number but I want to understand how to pass in the count from the first query. As it's written at the moment it gives this error: #1111 - Invalid use of group function

Answer 1

UPDATE
    `monitoring`
SET
    `times` = (
        SELECT
            COUNT(*)
        FROM
            `sales`
        WHERE
            `EAN` = '5052931107087'
    )
WHERE
    `EAN` = '5052931107087'