如何从一个位域获得真/假计数到两个单独的列
我需要创build一个查询，将True（1）和False（0）的数量从一个位字段中分成两个单独的列。
我join了3张桌子，需要它是这样的：
属性| 类| 通过| 失败
我将分组在属性和类。
像这样的东西：
SUM(CASE WHEN ColumnName = 1 THEN 1 ELSE 0 END) AS Pass, SUM(CASE WHEN ColumnName = 0 THEN 1 ELSE 0 END) AS Fail 这工作（至less在SQL 2008）
SELECT SUM(Passed + 0) PASS , SUM(1 - Passed) FAIL
在第一个和中，我将0加到Passed中，作为从位转换为int的简短方式，因为不能直接对位进行求和。
尝试：
declare @table table (columnName bit) insert into @table values (1) insert into @table values (1) insert into @table values (1) insert into @table values (1) insert into @table values (1) insert into @table values (0) insert into @table values (0) insert into @table values (0) insert into @table values (0) SELECT SUM(CASE WHEN ColumnName = 1 THEN 1 ELSE 0 END) AS True1 , SUM(CASE WHEN ColumnName = 0 THEN 1 ELSE 0 END ) AS False0 from @Table
OUTPUT：
True1 False0 ----------- ----------- 5 4 (1 row(s) affected)
SELECT Attribute, Class, SUM(CASE BitField WHEN 1 THEN 1 ELSE 0 END) AS [Pass], SUM(CASE BitField WHEN 0 THEN 1 ELSE 0 END) AS [Fail] FROM Table GROUP BY Attribute, Class
另一个select是
SELECT Attribute, Class COUNT(CASE WHEN ColumnName = 1 THEN 1 END) Pass, COUNT(CASE WHEN ColumnName = 0 THEN 1 END) Fail FROM YourTable GROUP BY Attribute, Class
