sql-server - 如何将位字段的真/假计数分为两个单独的列

Question

我需要创建一个查询，它将 True(1) 和 False(0) 的数量相加到一个位字段中的两个单独的列中。

我要加入 3 张桌子，需要它是这样的：

属性 | 班级 | 通行证 | 失败

我将按属性和类进行分组。

Answer 1

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

Answer 2

这有效（至少在 SQL 2008 中）

SELECT SUM(Passed + 0) PASS , SUM(1 - Passed) FAIL

我将第一个总和中的 Passed 添加 0 作为从位转换为 int 的简便方法，因为您不能直接对位求和。

Answer 3

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

Answer 4

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

输出：

True1       False0
----------- -----------
5           4

(1 row(s) affected)

Answer 5

另一种选择是

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

Answer 6

还有一种选择：

SELECT 
   Attribute, 
   Class,
   COUNT(BoolColumnName = 1 or NULL) Pass,
   COUNT(BoolColumnName = 0 or NULL) Fail 
FROM Table
GROUP BY Attribute, Class