Question

我有一个关于计算同一个表中同一行中多个字段的问题。展示我需要的最简单的方法是提供一个例子。我有report_number，writer1，loc1，writer2，loc2列。你可以打电话给我的表report_master。我的表看起来像这样：

    Report_Number,  writer1,    loc1,   writer2,    loc2
    1               123         1       456         2    
    2               456         2       789         3   
    3               789         3       123         1    
    4               789         3       123         1    
    5               456         2       789         3    
    6               123         1       456         2    
    7               123         1       789         3    
    8               456         2       123         1    
    9               789         3       123         1    
    10              123         1       456         2

输出：

    Reports,    writer
    8           123    
    6           456    
    6           789

我已经尝试过并且无法弄清楚查询以获取作者参与的报告数量。如果报告在writer1或writer2字段中，则作者将获得报告。我想将我的查询基于日期范围和loc。因此，如果我输入一个日期范围（该表确实有一个日期字段）和一个loc＃（包括搜索loc1和loc2），我会得到一些看起来像结果表的东西。

提前感谢您的帮助。我将在SQL SSRS中使用它。

Answer 1

SELECT COUNT(*) AS Reports, q.writer
    FROM (SELECT writer1 AS writer
              FROM YourTable
              WHERE loc1 = 1
          UNION ALL
          SELECT writer2 AS writer
              FROM YourTable
              WHERE loc2 = 1) q
   GROUP BY q.writer

Answer 2

最直接的方法是对每个作家字段的选择联合计数

SELECT COUNT(report_number) reports, 
       writer 
FROM   (SELECT report_number, 
               writer1  as writer
        FROM   table 
        UNION ALL 
        SELECT report_number 
               writer2 as writer
        FROM   table) t
GROUP  BY writer

另一个选择是使用UNPIVOT条款，但如果您的UNION SELECT不是微不足道的话，那么它真的是值得的

SELECT COUNT(report_number), 
       writer 
FROM   (SELECT report_number, 
               writer1, 
               writer2 
        FROM   reports) p UNPIVOT (writer FOR writer_type IN (writer1, writer2) 
       )AS 
       unpvt 
GROUP  BY writer

请参阅working sample here

计算多个字段同一行 - SQL

2 个答案: