选择Distinct SQL，其总数为distinct

Question

我希望制作一个select语句，选择一行中的所有不同项，并提供每个结果的总数

SELECT DISTINCT [Column 16] FROM [tab]

那就是我的TSQL走了多远

Answer 1

您在寻找

吗？

SELECT [Column 16], COUNT(*) 
FROM [tab]
GROUP BY [Column 16]
--WITH ROLLUP (if you need to the total )
ORDER BY COUNT(*) 

您可以将DESC关键字附加到查询的末尾，例如ORDER BY COUNT(*) DESC，如果您希望结果集按降序排序，或ASC升序（默认为升序，你可以省略它。）

Answer 2

当您GROUP BY时，您会得到[第16栏]的明确列表。然后你可以使用它的聚合函数。

SELECT [Column 16], Sum ( [Column To Sum] ) Total_T1
FROM [tab]
Group By [Column 16]

如果您想按多列分组，它们应该出现在select和GROUP BY

中

SELECT [Column 16], [Column 17], Sum ( [Column To Sum] ) Total_T1
FROM [tab]
Group By [Column 16], [Column 17]

您还可以指定多个聚合（这些聚合不会出现在group by子句

中

SELECT [Column 16], [Column 17], 
      Sum ( [Column To Sum] ) Total_T1,
      Count ( [Column To Sum] ) NumOf_T1,
      Avg ( [Column To Sum] ) Avg_T1,
      Min ( [Column To Sum] ) Min_T1,
      Max ( [Column To Sum] ) Max_T1
FROM [tab]
Group By [Column 16], [Column 17]