Question

我有大约20张表，包括学生的考试记录。我试图找出我的问题（学生ID = sID，即分数1：s1）：学生表:(学生reg.data）

sID   name   surname   regDate     photo           ........
891   Mike   Jackson   01.01.2013  82342984.png    ....

表A :(学生成绩）

sID   exam    s1    s2    s3    s4
891   6       0     0     0     20  > student 891 attended exam 6
891   10      30    80    100   75  > student 891 attended exam 10

（count = 2）

表B :(学生文件，即：文件1：d1）

sID   d1      d2     d3     d4     d5     d6
891   true    false  true   true   true   true

（count = 1）

表C :(学生留言）

mID   from    to    subject    message
1     10      891   any sub.   any message... > student 891 received messages (look "to")
1     10      891   mes2       other message... 
1     29      891   mes3       another message...

（count = 3）

表D :(学生付款）

sID   pID    amount    date   details

（此表中没有学生记录，count = 0）

.....和上面的类似表格。

我想要一个如下结果：

sID   name   surname   scoreCount   docCount   messageCount   paymentCount .....
891   Mike   Jackson   2            1          3              0            ...
892   Susan  Button    0            3          10             0            ...
893   Ahmad  Malisi    1            0          5              2            ...
894   any    any       4            1          0              0            ...
...
..

Answer 1

你试过这个吗？

Select sid,name,surname,
       (Select count(*) From student_scores Where Sid = S.Sid ) as scoreCount ,
       (Select count(*) From student_documents Where Sid = S.Sid ) as docCount ,
       (Select count(*) From student_messages Where to= S.Sid ) as messageCount  ,
       (Select count(*) From student_payments Where Sid = S.Sid ) as paymentCount ,
        .
        .
        .
From StudentsTables S
Where Sid=891

Answer 2

Select sid,name,surname,
isnull(sscnt,0)  ,isnull(sdcnt  ,0)  ,isnull(spcnt  ,0)  ,isnull(smcnt,0)  

From StudentsTables S
join  (Select Sid,count(Sid) sscnt From student_scores group by Sid) ss
on ss.sid=s.sid
join  (Select Sid,count(Sid) sdcnt  From student_documents group by Sid) sd
on sd.sid=s.sid
join  (Select Sid,count(Sid) spcnt  From student_payments group by Sid) sp
on sp.sid=s.sid
join  (Select Sid,count(Sid) smcnt  From student_messages group by Sid) sm
on sm.sid=s.sid

这将查询所有SId（s）

包括计数在内的精选查询

2 个答案: