MySQL 从结果集中选择TOP 1
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时间：2020-08-31 21:10:07 来源:igfitidea点击:
Select TOP 1 from the result set
提问by user1894647
I would like to retrieve the top 1 value of result set of query which is connected using Union
我想检索使用 Union 连接的查询结果集的前 1 个值
SELECT TOP 1 * FROM
(
SELECT paused_time as end_time
FROM production_time
WHERE created_time = curdate()
UNION
SELECT resumed_time as end_time
FROM pause_timer
WHERE created_time = curdate()
UNION
SELECT end_time as end_time
FROM timer_idle
WHERE created_time = curdate()
) as end_time
ORDER BY end_time DESC
But could not get the expected result.
但是没有得到预期的结果。
回答by Wibbler
There is no TOPkeyword in MySQL as far as I am aware. What you require is Limit:
TOP据我所知，MySQL 中没有关键字。你需要的是Limit：
SELECT * FROM
(
SELECT paused_time as end_time FROM production_time WHERE created_time = curdate()
UNION
SELECT resumed_time as end_time FROM pause_timer WHERE created_time = curdate()
UNION
SELECT end_time as end_time FROM timer_idle WHERE created_time = curdate()
) as end_time
ORDER BY end_time DESC
LIMIT 1
