下面是一个在Oracle上运行的快速而简单的版本:

select sum(case a when null then 1 else 0) "Null values",
       sum(case a when null then 0 else 1) "Non-null values"
from us

Try

SELECT 
   SUM(ISNULL(a)) AS all_null,
   SUM(!ISNULL(a)) AS all_not_null
FROM us;

简单!

我有一个类似的问题:要计算所有不同的值，空值也算作1。简单的计数在这种情况下不起作用，因为它不考虑空值。

下面是一个适用于SQL的代码片段，不涉及选择新值。 基本上，执行distinct后，还使用row_number()函数返回新列(n)中的行号，然后对该列执行计数:

SELECT COUNT(n)
FROM (
    SELECT *, row_number() OVER (ORDER BY [MyColumn] ASC) n
    FROM (
        SELECT DISTINCT [MyColumn]
                    FROM [MyTable]
        ) items  
) distinctItems

SELECT SUM(NULLs) AS 'NULLS', SUM(NOTNULLs) AS 'NOTNULLs' FROM 
    (select count(*) AS 'NULLs', 0 as 'NOTNULLs' FROM us WHERE a is null
    UNION select 0 as 'NULLs', count(*) AS 'NOTNULLs' FROM us WHERE a is not null) AS x

这很糟糕，但它将返回一个带有2个cols的记录，指示null和非null的计数。

SELECT
    ALL_VALUES
    ,COUNT(ALL_VALUES)
FROM(
        SELECT 
        NVL2(A,'NOT NULL','NULL') AS ALL_VALUES 
        ,NVL(A,0)
        FROM US
)
GROUP BY ALL_VALUES

在我的例子中，我想要多列之间的“空分布”:

SELECT
       (CASE WHEN a IS NULL THEN 'NULL' ELSE 'NOT-NULL' END) AS a_null,
       (CASE WHEN b IS NULL THEN 'NULL' ELSE 'NOT-NULL' END) AS b_null,
       (CASE WHEN c IS NULL THEN 'NULL' ELSE 'NOT-NULL' END) AS c_null,
       ...
       count(*)
FROM us
GROUP BY 1, 2, 3,...
ORDER BY 1, 2, 3,...

根据“……它可以很容易地扩展到更多的列，只要需要