Question

我在SQL Server数据库中有这个SQL：

SELECT   E.CreatedDate AS CreatedDate,
         E.ExamId   AS ExamId,
         E.SubjectId As SubjectId,
         E.Title    AS Name,
         E.Text     AS Text,
         E.ExamTypeId AS ExamTypeId
FROM     AdminTest A, 
         Exam E
WHERE    A.ExamId = E.ExamId
AND      A.TestStatusId = 3

有人可以告诉我，我可以这样做，以便显示每次考试的AdminTests数量。现在它返回：

2014-09-27 06:08:43.673 2322        1           Custom Exam 1                                      asfdsadfsadf                                                                                                                                                                                                                                                     3
2013-08-22 15:16:00.000 1           1           Exam 1                                             sdfsdf                                                                                                                                                                                                                                                           1
2013-08-22 15:16:00.000 1           1           Exam 1                                             sdfsdf                                                                                                                                                                                                                                                           1
2013-08-22 15:16:00.000 1           1           Exam 1                                             sdfsdf                                                                                                                                                                                                                                                           1

我想要的是在每个行的末尾看到两行和一列，这些数据显示为1，然后是3。

Answer 1

您应该使用group by和count汇总功能：

SELECT E.CreatedDate AS CreatedDate,
       E.ExamId   AS ExamId,
       E.SubjectId As SubjectId,
       E.Title    AS Name,
       E.Text     AS Text,
       E.ExamTypeId AS ExamTypeId,
       COUNT(*) AS TotalCount
FROM     AdminTest A 
JOIN     Exam E ON A.ExamId = E.ExamId
WHERE    A.TestStatusId = 3
GROUP BY E.CreatedDate,
         E.ExamId,
         E.SubjectId,
         E.Title,
         E.Text,
         E.ExamTypeId

Answer 2

我认为您正在寻找GROUP BY条款：

SELECT   
    COUNT(*),
    E.ExamId   AS ExamId
FROM     AdminTest A, 
         Exam E
WHERE    A.ExamId = E.ExamId
AND      A.TestStatusId = 3
GROUP BY ExamId;

如何在SQL中对某些行进行分组并显示计数？

2 个答案: