我有一个出席的MYSQL表,其记录如下:
Id DateTime Door Employee_id
1 2016-01-01 08:00:00 In 100
2 2016-01-01 09:00:00 Out 100
3 2016-01-01 09:15:00 In 100
4 2016-01-01 09:30:00 In 100
5 2016-01-01 10:00:00 Out 100
6 2016-01-01 11:00:00 In 100
7 2016-01-01 12:00:00 In 100
8 2016-01-01 13:00:00 In 100
9 2016-01-01 13:30:00 Out 100
10 2016-01-01 14:00:00 Out 100
11 2016-01-01 15:00:00 In 100
我希望输出为Last Clock In和Last Clock Out,如下所示。如果在最后一个时钟输入后没有时钟输出,则忽略时钟。
Id Clock In Clock Out Employee Id
1 2016-01-01 08:00:00 2016-01-01 09:00:00 100
2 2016-01-01 09:30:00 2016-01-01 10:00:00 100
3 2016-01-01 13:00:00 2016-01-01 14:00:00 100
我真的不知道如何执行此操作。我已经问过我的同事了,但是没有运气。能感谢你们的任何帮助。提前谢谢。
答案 0 :(得分:1)
这是差距问题的变体。首先列举in
和out
s,使连续值组具有相同的值。然后你可以使用聚合。
所以:
select (@rn := @rn + 1) as id,
max(case when door = 'in' then datetime end) as clockin,
max(case when door = 'out' then datetime end) as clockout
from (select t.*,
@grp := if(@d = door, @grp,
if(@d := door, @grp + 1, @grp + 1)
) as grp
from t cross join
(select @d := '', @grp := 0) param
order by id
) t cross join
(select @rn := 0) param
group by floor((grp - 1) / 2)
Here是一个SQL小提琴。
答案 1 :(得分:1)
这是一个带演示的解决方案。
SQL:
-- data
create table attendance(Id int, DateTime datetime, Door char(20));
INSERT INTO attendance VALUES
( 1, '2016-01-01 08:00:00', 'In'),
( 2, '2016-01-01 09:00:00', 'Out'),
( 3, '2016-01-01 09:15:00', 'In'),
( 4, '2016-01-01 09:30:00', 'In'),
( 5, '2016-01-01 10:00:00', 'Out'),
( 6, '2016-01-01 11:00:00', 'In'),
( 7, '2016-01-01 12:00:00', 'In'),
( 8, '2016-01-01 13:00:00', 'In'),
( 9, '2016-01-01 13:30:00', 'Out'),
( 10, '2016-01-01 14:00:00', 'Out'),
( 11, '2016-01-01 15:00:00', 'In');
SELECT * FROM attendance;
-- SQL needed:
SELECT
@id:=@id+1 Id,
MAX(IF(Door = 'In', DateTime, NULL)) `Check In`,
MAX(IF(Door = 'Out', DateTime, NULL)) `Check Out`
FROM
(SELECT
*,
CASE
WHEN
(door = 'In' AND @last_door = '') OR
(door = 'In' AND @last_door = 'In') OR
(door = 'Out' AND @last_door = 'In') OR
(door = 'Out' AND @last_door = 'Out')
THEN @group_num
WHEN
(door = 'In' AND @last_door = 'Out')
THEN @group_num:=@group_num+1
ELSE 0
END door_group,
@last_door:=Door
FROM attendance
JOIN (SELECT @group_num:=1) a
) t JOIN (SELECT @id:=0) b
GROUP BY t.door_group
HAVING SUM(Door = 'In') > 0 AND SUM(Door = 'Out') > 0;
输出:
mysql> SELECT * FROM attendance;
+------+---------------------+------+
| Id | DateTime | Door |
+------+---------------------+------+
| 1 | 2016-01-01 08:00:00 | In |
| 2 | 2016-01-01 09:00:00 | Out |
| 3 | 2016-01-01 09:15:00 | In |
| 4 | 2016-01-01 09:30:00 | In |
| 5 | 2016-01-01 10:00:00 | Out |
| 6 | 2016-01-01 11:00:00 | In |
| 7 | 2016-01-01 12:00:00 | In |
| 8 | 2016-01-01 13:00:00 | In |
| 9 | 2016-01-01 13:30:00 | Out |
| 10 | 2016-01-01 14:00:00 | Out |
| 11 | 2016-01-01 15:00:00 | In |
+------+---------------------+------+
11 rows in set (0.00 sec)
mysql>
mysql> -- SQL needed:
mysql> SELECT
-> @id:=@id+1 Id,
-> MAX(IF(Door = 'In', DateTime, NULL)) `Check In`,
-> MAX(IF(Door = 'Out', DateTime, NULL)) `Check Out`
-> FROM
-> (SELECT
-> *,
-> CASE
-> WHEN
-> (door = 'In' AND @last_door = '') OR
-> (door = 'In' AND @last_door = 'In') OR
-> (door = 'Out' AND @last_door = 'In') OR
-> (door = 'Out' AND @last_door = 'Out')
-> THEN @group_num
-> WHEN
-> (door = 'In' AND @last_door = 'Out')
-> THEN @group_num:=@group_num+1
-> ELSE 0
-> END door_group,
-> @last_door:=Door
-> FROM attendance
-> JOIN (SELECT @group_num:=1) a
-> ) t JOIN (SELECT @id:=0) b
-> GROUP BY t.door_group
-> HAVING SUM(Door = 'In') > 0 AND SUM(Door = 'Out') > 0;
+------+---------------------+---------------------+
| Id | Check In | Check Out |
+------+---------------------+---------------------+
| 1 | 2016-01-01 08:00:00 | 2016-01-01 09:00:00 |
| 2 | 2016-01-01 09:30:00 | 2016-01-01 10:00:00 |
| 3 | 2016-01-01 13:00:00 | 2016-01-01 14:00:00 |
+------+---------------------+---------------------+
3 rows in set (0.00 sec)