SQL全外连接
[英]SQL Full Outer Join
问题描述
I have a table named 'Logs' with the following values : 
我有一个名为“ Logs”的表，具有以下值：
CheckDate CheckType CheckTime
-------------------------------------------
2011-11-25 IN 14:40:00
2011-11-25 OUT 14:45:00
2011-11-25 IN 14:50:00
2011-11-25 OUT 14:55:00
2011-11-25 IN 15:00:00
2011-11-25 OUT 15:05:00
2011-11-25 IN 15:15:00
2011-11-25 OUT 15:20:00
2011-11-25 IN 15:25:00
2011-11-25 OUT 15:30:00
2011-11-25 OUT 15:40:00
2011-11-25 IN 15:45:00
I want to use the previous table to produce a result of: 我想使用上一个表来产生以下结果：
CheckDate CheckIn CheckOut
-----------------------------------------
2011-11-25 14:40:00 14:45:00
2011-11-25 14:50:00 14:55:00
2011-11-25 15:00:00 15:05:00
2011-11-25 15:15:00 15:20:00
2011-11-25 15:25:00 15:30:00
2011-11-25 NULL 15:40:00
2011-11-25 15:45:00 NULL
So far I have come up with this result set : 到目前为止，我已经提出了以下结果集：
CheckDate CheckIn CheckOut
-----------------------------------------
2011-11-25 14:40:00 14:45:00
2011-11-25 14:50:00 14:55:00
2011-11-25 15:00:00 15:05:00
2011-11-25 15:15:00 15:20:00
2011-11-25 15:25:00 15:30:00
2011-11-25 15:45:00 NULL
The problem is I cannot generate the log without CheckIns : 问题是没有CheckIns我无法生成日志：
CheckDate CheckIn CheckOut
-----------------------------------------
2011-11-25 NULL 15:40:00
The sequence of CheckIn - CheckOut pairing and order is in increasing time value. CheckIn-CheckOut配对和顺序的顺序是增加时间值。
EDIT : This is my current query 编辑：这是我当前的查询
SELECT Ins.CheckDate,
Ins.CheckTime,
Outs.CheckTime
FROM (SELECT CheckDate,
CheckTime
FROM Logs
WHERE CheckType = 'I') Ins
FULL OUTER JOIN
(SELECT CheckDate,
CheckTime
FROM Logs
WHERE CheckType = 'O') Outs
ON Ins.CheckDate = Outs.CheckDate AND
Ins.CheckTime < Outs.CheckTime
2 个解决方案
解决方案1
5 已采纳 2011-11-26 02:03:53
This should work: 这应该工作：
;WITH x AS (
SELECT CheckDate, CheckType, CheckTime
,row_number() OVER (ORDER BY CheckDate, CheckTime) As rn
FROM #t
)
SELECT CASE WHEN x.CheckType = 'IN' OR x.rn = 1 THEN x.CheckDate
ELSE y.CheckDate END AS CheckDate
,CASE WHEN x.CheckType = 'IN' THEN x.CheckTime ELSE NULL END AS CheckIn
,CASE WHEN y.CheckType = 'OUT' THEN y.CheckTime
WHEN x.CheckType = 'OUT' THEN x.CheckTime ELSE NULL END AS CheckOut
FROM x
LEFT JOIN x AS y ON y.rn = x.rn + 1
WHERE x.CheckType = 'IN'
OR y.CheckType = 'OUT'
OR x.rn = 1
It produces exactly the output requested and covers special cases where 它会精确地产生所需的输出，并涵盖特殊情况，其中
-
OUTis followed by anotherOUT(missingIN)OUT之后是另一个OUT（缺少IN） -
INis followed by anotherIN(missingOUT)IN之后是另一个IN（缺少OUT） -
INis followed by nothing (last row).IN后面没有任何内容（最后一行）。 - first row starts with
OUT.第一行以OUT开头。
Try the working demo on data.SE . 尝试在data.SE上运行的演示 。
解决方案2
0 2011-11-26 04:33:59
Some of the optimizers doesn't support "FULL OUTER JOIN" of sql So, Query should be: 一些优化器不支持sql的“ FULL OUTER JOIN”，因此查询应该是：
SELECT Ins.CheckDate,
Ins.CheckTime,
Outs.CheckTime
FROM (SELECT CheckDate,
CheckTime
FROM Logs
WHERE CheckType = 'I') Ins
LEFT OUTER JOIN
(SELECT CheckDate,
CheckTime
FROM Logs
WHERE CheckType = 'O') Outs
ON Ins.CheckDate = Outs.CheckDate AND
Ins.CheckTime < Outs.CheckTime
UNION
SELECT Ins.CheckDate,
Ins.CheckTime,
Outs.CheckTime
FROM (SELECT CheckDate,
CheckTime
FROM Logs
WHERE CheckType = 'I') Ins
RIGHT OUTER JOIN
(SELECT CheckDate,
CheckTime
FROM Logs
WHERE CheckType = 'O') Outs
ON Ins.CheckDate = Outs.CheckDate AND
Ins.CheckTime < Outs.CheckTime
声明:本站的技术帖子网页，遵循CC BY-SA 4.0协议，如果您需要转载，请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.