mysql - 有没有更好的方法来编写这个特定的查询？

Question

SELECT (res.phone_number_count + res.computer_count) AS user_count FROM (
    SELECT COUNT(DISTINCT phone_number_id) AS phone_number_count, COUNT(DISTINCT computer_id) AS computer_count
    FROM opinions
    WHERE case_id = 1
) AS res;

我正在尝试计算唯一的phone_number_ids 和computer_ids。

Answer 1

怎么样：

SELECT COUNT(DISTINCT phone_number_id) + COUNT(DISTINCT computer_id) AS user_count
FROM opinions
WHERE case_id = 1