Question

给出下表

ID  Teacher     lessondate              period  Group   Course  Room    Lnr     Count
167 teacher 1   2013-12-02 08:30:00.000 1       group 1 NE      room 1  223     1
168 teacher 1   2013-12-02 09:15:00.000 2       group 1 NE      room 1  224     1
169 teacher 1   2013-12-02 10:00:00.000 3       group 1 ENG     room 1  226     1
170 teacher 1   2013-12-02 11:00:00.000 4       group 1 VAKT    room 1  228     1
171 teacher 1   2013-12-02 11:45:00.000 5       group 1 DGV     room 1  227     1
172 teacher 1   2013-12-02 13:00:00.000 6       group 1 VAKT    room 1  228     1
183 teacher 1   2013-12-05 08:30:00.000 1       group 1 VAKT    room 2  228     1
184 teacher 1   2013-12-05 09:15:00.000 2       group 1 NE      room 2  223     2
185 teacher 1   2013-12-05 10:00:00.000 3       group 1 NE      room 2  223     2
186 teacher 1   2013-12-05 11:00:00.000 4       group 1 LB      room 1  222     2
187 teacher 1   2013-12-05 11:45:00.000 5       group 1 LB      room 1  222     2
188 teacher 1   2013-12-05 13:00:00.000 6       group 1 REK     room 1  225     1
189 teacher 1   2013-12-06 14:45:00.000 8       group 2 AAA             4       3
190 teacher 1   2013-12-06 15:30:00.000 9       group 2 AAA             4       3
191 teacher 1   2013-12-06 16:15:00.000 10      group 2 AAA             4       3

我想在SQL中使用以下条件生成count列：

计数是＆gt;如果期间在同一天且连续（期间）且课程编号（lnr）相等，则为1。

数据说明：

167和168：同一天，连续期间，课程数不等于=＆gt; count = 1
170和172：同一天，相同的课程编号，期间不连续=＆gt;计数= 1
184和185：同一天，同一课程编号，连续期间=＆gt;计数= 2，
189,190,191：同一天，同一课程编号，连续期间=＆gt;计数= 3

我猜它有分区，等等，但我的sql知识缺乏那部分：（

* 编辑： *我到目前为止的查询：

select distinct  a.*, blockHours 
from timetablerecords a 
join (
select distinct lessonnumber, convert(date,c.lessonDate) ld, count(distinct period) blockHours 
from timetablerecords c 
where teacher='teacher 1' 
group by  convert(date,c.lessonDate), c.lessonnumber, c.course 
) b 
on a.lessonNumber=b.lessonnumber and convert(date,a.lessonDate)= b.ld
where teacher='teacher 1' 
order by lessondate,period

这不考虑不连续（或不连续？）期间。使用上面的数据，对于id 170和172

，它返回count = 2

查询在MS SQL Azure数据库上运行输出应包含表中提到的所有列。只有上面没有显示的列，但结果也应该是“持续时间” 可以使用以下脚本创建表：

CREATE TABLE [dbo].[timetablerecords](
    [Id] [int] IDENTITY(1,1) NOT NULL,
    [teacher] [nvarchar](255) NOT NULL,
    [lessonDate] [datetime] NOT NULL,
    [period] [int] NOT NULL,
    [group] [nvarchar](255) NOT NULL,
    [course] [nvarchar](255) NOT NULL,
    [room] [nvarchar](255) NOT NULL,
    [lessonNumber] [nvarchar](255) NOT NULL,
    [lessonDuration] [int] NOT NULL,
    [locationCode] [nvarchar](255) NOT NULL)

sql计算一天的连续时间

0 个答案: