问题
I am making a simple time in and time out system. I have 3 pairs of in/out.
emp_id td_id status timestamp remarks
35 1 in 2013-12-19 10:15:09 late
35 2 out 2013-12-19 12:00:23 example
35 3 in 2013-12-19 13:00:23
35 4 out 2013-12-19 16:01:47
35 5 in 2013-12-19 18:01:17
35 6 out 2013-12-19 22:01:07
35 7 in 2013-12-20 10:00:12
Here's my query:
SELECT a1.emp_id, a1.status, a1.timestamp, a2.status, a2.timestamp, a3.status, a3.timestamp, a4.status, a4.timestamp, a5.status, a5.timestamp, a6.status, a6.timestamp
FROM overallrec a1
LEFT JOIN overallrec a2 ON a2.emp_id = a1.emp_id
AND a2.status = 'out'
LEFT JOIN overallrec a3 ON a3.emp_id = a1.emp_id
AND a3.status = 'in'
AND a3.timestamp <> a1.timestamp
LEFT JOIN overallrec a4 ON a4.emp_id = a1.emp_id
AND a4.status = 'out'
AND a4.timestamp <> a2.timestamp
LEFT JOIN overallrec a5 ON a5.emp_id = a1.emp_id
AND a5.status = 'in'
AND a5.timestamp <> a3.timestamp
LEFT JOIN overallrec a6 ON a6.emp_id = a1.emp_id
AND a6.status = 'in'
AND a6.timestamp <> a4.timestamp
WHERE a1.status = 'in'
Here's my result:
emp_id status timestamp status timestamp status timestamp status timestamp status timestamp status timestamp
35 in 2013-12-19 10:15:09 out 2013-12-19 12:00:23 in 2013-12-19 13:00:23 out 2013-12-19 16:01:47 in 2013-12-19 18:01:17 out 2013-12-19 22:01:07
35 in 2013-12-20 10:00:12 out 2013-12-19 12:00:23 in 2013-12-19 13:00:23 out 2013-12-19 16:01:47 in 2013-12-19 18:01:17 out 2013-12-19 22:01:07
Notice the first 'in' timestamp value row 2 is another date, but the next status timestamp and soon are repeating from the previous date. I want it to display null when still empty and not to copy the value on previous date. In other words, it should generate another row on day change.
Additional Remarks: when I add remarks at every input, it will be concatenated in the table result. I wanted it to be like this:
emp_id status timestamp status timestamp status timestamp status timestamp status timestamp status timestamp remarks
35 in 2013-12-19 10:15:09 out 2013-12-19 12:00:23 in 2013-12-19 13:00:23 out 2013-12-19 16:01:47 in 2013-12-19 18:01:17 out 2013-12-19 22:01:07 "Late, Example"
35 in 2013-12-20 10:00:12 null null null null null null null null null null "Straight time"
What should i do on my query? Or if not with the query, what else?
回答1:
Changed answer, i forgot to order by timestamp1,here's the final version that will take care of multiple employees :) sqlFiddle
SELECT T1.emp_id,T1.status1 as status1,T1.timestamp1 as timestamp1,
T1.status2 as status2,T1.timestamp2 as timestamp2,
T2.status1 as status3,T2.timestamp1 as timestamp3,
T2.status2 as status4,T2.timestamp2 as timestamp4,
T3.status1 as status5,T3.timestamp1 as timestamp5,
T3.status2 as status6,T3.timestamp2 as timestamp6
FROM
(SELECT * FROM
(SELECT IF(((@row+1)=4) OR (@prevEmpId<>a1.emp_id),@row:=1,@row:=@row+1) as row,a1.emp_id,a1.status as status1,a1.timestamp as timestamp1,
'out' as status2,
@prevEmpId:=a1.emp_id,
(SELECT min(timestamp) as timestamp2
FROM overallrec a2
WHERE a2.timestamp > a1.timestamp
AND a2.emp_id = a1.emp_id
AND a2.status = 'out') as timestamp2
FROM overallrec a1,(SELECT @row:=0,@prevEmpId:=0)r
WHERE a1.status = 'in'
ORDER BY a1.emp_id,timestamp1
)T100
WHERE row=1
)T1
LEFT JOIN
(SELECT * FROM
(SELECT IF(((@row+1)=4) OR (@prevEmpId<>a1.emp_id),@row:=1,@row:=@row+1) as row,a1.emp_id,a1.status as status1,a1.timestamp as timestamp1,
'out' as status2,
@prevEmpId:=a1.emp_id,
(SELECT min(timestamp) as timestamp2
FROM overallrec a2
WHERE a2.timestamp > a1.timestamp
AND a2.emp_id = a1.emp_id
AND a2.status = 'out') as timestamp2
FROM overallrec a1,(SELECT @row:=0,@prevEmpId:=0)r
WHERE a1.status = 'in'
ORDER BY a1.emp_id,timestamp1
)T200
WHERE row=2
)T2
ON T1.emp_id = T2.emp_id AND DATE_FORMAT(T2.timestamp1,'%Y-%m-%d') = DATE_FORMAT(T1.timestamp1,'%Y-%m-%d')
LEFT JOIN
(SELECT * FROM
(SELECT IF(((@row+1)=4) OR (@prevEmpId<>a1.emp_id),@row:=1,@row:=@row+1) as row,a1.emp_id,a1.status as status1,a1.timestamp as timestamp1,
'out' as status2,
@prevEmpId:=a1.emp_id,
(SELECT min(timestamp) as timestamp2
FROM overallrec a2
WHERE a2.timestamp > a1.timestamp
AND a2.emp_id = a1.emp_id
AND a2.status = 'out') as timestamp2
FROM overallrec a1,(SELECT @row:=0,@prevEmpId:=0)r
WHERE a1.status = 'in'
ORDER BY a1.emp_id,timestamp1
)T300
WHERE row=3
)T3
ON T1.emp_id = T3.emp_id AND DATE_FORMAT(T3.timestamp1,'%Y-%m-%d') = DATE_FORMAT(T1.timestamp1,'%Y-%m-%d')
However this query won't work if employee clocks in one day and then then clocks out the next day because it's making use of the same day check in order to LEFT JOIN
OP asked for a view, but View in mySQL doesn't allow variables so I tried to write a different query (not using variables) such as this one (sqlFiddle)
SELECT T4.emp_id,T4.status1,T4.timestamp1,T4.status2,T4.timestamp2,
T4.status3,T4.timestamp3,T4.status4,T4.timestamp4,T4.status5,T4.timestamp5,
'out' as status6,
(SELECT min(timestamp)
FROM overallrec a
WHERE a.timestamp > T4.timestamp5
AND a.emp_id = T4.emp_id
AND a.status = 'out') as timestamp6
FROM
(SELECT T3.emp_id,T3.status1,T3.timestamp1,T3.status2,T3.timestamp2,
T3.status3,T3.timestamp3,T3.status4,T3.timestamp4,
'in' as status5,
(SELECT min(timestamp)
FROM overallrec a
WHERE a.timestamp > T3.timestamp4
AND a.emp_id = T3.emp_id
AND a.status = 'in') as timestamp5
FROM
(SELECT T2.emp_id,T2.status1,T2.timestamp1,T2.status2,T2.timestamp2,
T2.status3,T2.timestamp3,
'out' as status4,
(SELECT min(timestamp)
FROM overallrec a
WHERE a.timestamp > T2.timestamp3
AND a.emp_id = T2.emp_id
AND a.status = 'out') as timestamp4
FROM
(SELECT T1.emp_id,T1.status1,T1.timestamp1,T1.status2,T1.timestamp2,
'in' as status3,
(SELECT min(timestamp)
FROM overallrec a
WHERE a.timestamp > T1.timestamp2
AND a.emp_id = T1.emp_id
AND a.status = 'in') as timestamp3
FROM
(SELECT a1.emp_id,a1.status as status1,a1.timestamp as timestamp1,
'out' as status2,
(SELECT min(timestamp) as timestamp2
FROM overallrec a2
WHERE a2.timestamp > a1.timestamp
AND a2.emp_id = a1.emp_id
AND a2.status = 'out') as timestamp2
FROM overallrec a1
WHERE a1.status = 'in'
AND NOT EXISTS (SELECT 1 FROM overallrec e
WHERE e.timestamp < a1.timestamp
AND e.emp_id = a1.emp_id
AND DATE_FORMAT(e.timestamp,'%Y-%m-%d') =
DATE_FORMAT(a1.timestamp,'%Y-%m-%d'))
)T1
)T2
)T3
)T4;
Unfortunately, mySQL views don't allow subqueries (Subqueries cannot be used in the FROM clause of a view.) but what mySQL allow is to create Views on top of views so here is the views created (sqlFiddle)
CREATE VIEW T100 AS
SELECT a1.emp_id,a1.status as status1,a1.timestamp as timestamp1,
'out' as status2,
(SELECT min(timestamp) as timestamp2
FROM overallrec a2
WHERE a2.timestamp > a1.timestamp
AND a2.emp_id = a1.emp_id
AND a2.status = 'out') as timestamp2
FROM overallrec a1
WHERE a1.status = 'in'
AND NOT EXISTS (SELECT 1 FROM overallrec e
WHERE e.timestamp < a1.timestamp
AND e.emp_id = a1.emp_id
AND DATE_FORMAT(e.timestamp,'%Y-%m-%d') =
DATE_FORMAT(a1.timestamp,'%Y-%m-%d'));
CREATE VIEW T200 AS
SELECT T1.emp_id,T1.status1,T1.timestamp1,T1.status2,T1.timestamp2,
'in' as status3,
(SELECT min(timestamp)
FROM overallrec a
WHERE a.timestamp > T1.timestamp2
AND a.emp_id = T1.emp_id
AND a.status = 'in') as timestamp3
FROM T100 AS T1;
CREATE VIEW T300 AS
SELECT T2.emp_id,T2.status1,T2.timestamp1,T2.status2,T2.timestamp2,
T2.status3,T2.timestamp3,
'out' as status4,
(SELECT min(timestamp)
FROM overallrec a
WHERE a.timestamp > T2.timestamp3
AND a.emp_id = T2.emp_id
AND a.status = 'out') as timestamp4
FROM T200 AS T2;
CREATE VIEW T400 AS
SELECT T3.emp_id,T3.status1,T3.timestamp1,T3.status2,T3.timestamp2,
T3.status3,T3.timestamp3,T3.status4,T3.timestamp4,
'in' as status5,
(SELECT min(timestamp)
FROM overallrec a
WHERE a.timestamp > T3.timestamp4
AND a.emp_id = T3.emp_id
AND a.status = 'in') as timestamp5
FROM T300 AS T3;
CREATE VIEW myFinalView AS
SELECT T4.emp_id,T4.status1,T4.timestamp1,T4.status2,T4.timestamp2,
T4.status3,T4.timestamp3,T4.status4,T4.timestamp4,T4.status5,T4.timestamp5,
'out' as status6,
(SELECT min(timestamp)
FROM overallrec a
WHERE a.timestamp > T4.timestamp5
AND a.emp_id = T4.emp_id
AND a.status = 'out') as timestamp6
FROM T400 AS T4;
so there we have it a VIEW :) called myFinalView
Here's a myFinalView with remarks (check this sqlFiddle with remarks in the VIEW)
回答2:
You can try adding a group by to your query:
group by a1.emp_id, date(a1.timestamp), date(a2.timestamp), date(a3.timestamp),
date(a4.timestamp), date(a5.timestamp), date(a6.timestamp)
To be honest, though, I would do the whole query as a conditional aggregation with "in" and "out" on one row. This would work for one pair, but not three. I don't understand why you want three pairs on one row. What about employees that only have two pairs in one day? Or who have four pairs?
来源：https://stackoverflow.com/questions/20672754/complicated-select-query-for-a-simple-in-out-record