MySQL 如何将mysql表行转换为列
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时间：2020-08-31 17:38:55 来源:igfitidea点击:
How to transpose mysql table rows into columns
提问by dmikester1
Here is what my current mysql table looks like:
这是我当前的 mysql 表的样子：
PunchID EmpID PunchEvent PunchDateTime
1 0456 clockin 5/14/2013 8:36:26 AM
48 0456 breakout 5/14/2013 12:01:29 PM
53 0456 breakin 5/14/2013 12:28:31 PM
54 0456 clockout 5/14/2013 2:28:33 PM
57 0456 clockin 5/15/2013 7:38:34 AM
58 0456 breakout 5/15/2013 7:38:39 AM
59 0456 breakin 5/15/2013 7:38:41 AM
60 0456 clockout 5/15/2013 7:38:42 AM
Now I want to return a result set that is grouped based on the day of the week like so:
现在我想返回一个基于星期几分组的结果集，如下所示：
Day ClockIn BreakOut BreakIn ClockOut
Tuesday 8:36:26 AM 12:01:29 PM 12:28:31 PM 2:28:33 PM
Wednesday 7:38:34 AM etc, etc...
This is my current query. But it only returns the first punch for each day.
这是我当前的查询。但它只返回每天的第一拳。
SELECT DATE_FORMAT(PunchDateTime, '%W') as day, PunchEvent, DATE_FORMAT(PunchDateTime, '%l:%m:%s %p') as time FROM timeclock_punchlog WHERE EmpID = '0456' GROUP BY DATE(PunchDateTime) ORDER BY PunchDateTime ASC;
Can someone help me with this? Thanks Mike
有人可以帮我弄这个吗？谢谢迈克
回答by John Woo
SELECT DATE_FORMAT(PunchDateTime, '%W') DAY,
MAX(CASE WHEN PunchEvent = 'ClockIn' THEN DATE_FORMAT(PunchDateTime, '%r') END) ClockIn,
MAX(CASE WHEN PunchEvent = 'BreakOut' THEN DATE_FORMAT(PunchDateTime, '%r') END) BreakOut,
MAX(CASE WHEN PunchEvent = 'BreakIn' THEN DATE_FORMAT(PunchDateTime, '%r') END) BreakIn,
MAX(CASE WHEN PunchEvent = 'ClockOut' THEN DATE_FORMAT(PunchDateTime, '%r') END) ClockOut
FROM tableName
WHERE EmpID = 456
GROUP BY DATE_FORMAT(PunchDateTime, '%W')
ORDER BY PunchDateTime
OUTPUT
输出
╔═══════════╦═════════════╦═════════════╦═════════════╦═════════════╗
║ DAY ║ CLOCKIN ║ BREAKOUT ║ BREAKIN ║ CLOCKOUT ║
╠═══════════╬═════════════╬═════════════╬═════════════╬═════════════╣
║ Tuesday ║ 08:36:26 AM ║ 12:01:29 PM ║ 12:28:31 PM ║ 02:28:33 PM ║
║ Wednesday ║ 07:38:34 AM ║ 07:38:39 AM ║ 07:38:41 AM ║ 07:38:42 AM ║
╚═══════════╩═════════════╩═════════════╩═════════════╩═════════════╝
