单个查询中的多个计数（*）

Question

我需要一个查询以基于某些条件（oracle）来获取计数。

select count(*) AS TOTAL_ROWS from table

select count(*) AS TOTAL_ERROR_ROWS from table where ERROR_CODE is not null

select count(*) AS TOTAL_SUCCESS_ROWS from table where ERROR_CODE is  null

我想在1个查询中获取所有三个结果。 我在谷歌搜索后尝试如下所示，但它不起作用：

select
   count(*) as TotalCount,
   count(case when { where ERROR_CODE is not null} then 1 else 0 end) as QualifiedCount
from
   wli_qs_report_attribute

select count(*) as TOTAL,
    count(case when ERROR_CODE is not null then 1 else 0 end) as ExecCount,
from wli_qs_report_attribute

它不起作用。

Answer 1

SELECT TOTAL_ROWS, TOTAL_ERROR_ROWS, TOTAL_ROWS-TOTAL_ERROR_ROWS AS TOTAL_SUCCESS_ROWS FROM ( SELECT COUNT(*) AS TOTAL_ROWS , COUNT(ERROR_CODE) AS TOTAL_ERROR_ROWS FROM table ) AS T

Answer 2

您可以使用UNION ：

select count(*) AS TOTAL_ROWS from table

UNION

select count(*) AS TOTAL_ROWS from table where ERROR_CODE is not null

UNION

select count(*) AS TOTAL_ROWS from table where ERROR_CODE is  null

但是它将在一列中显示所有三个COUNT 。 要在三个不同的列中显示它，请尝试以下操作：

SELECT COUNT(*) AS TOTAL_ROWS
     , COUNT(CASE WHEN ERROR_CODE IS NOT NULL THEN * END) AS TOTAL_ERROR_ROWS
     , COUNT(CASE WHEN ERROR_CODE IS NULL THEN * END) AS TOTAL_SUCCESS_ROWS
FROM table 

Answer 3

SELECT COUNT(*) AS TOTAL_ROWS,
       SUM(CASE WHEN ERROR_CODE IS NOT NULL THEN 1 end) AS TOTAL_ERROR_ROWS,
       SUM(CASE WHEN ERROR_CODE IS NULL THEN 1 END) AS TOTAL_SUCCESS_ROWS 
FROM table

Answer 4

代替：

count(case when ERROR_CODE is not null then 1 else 0 end) as ExecCount

尝试：

sum(case when ERROR_CODE is not null then 1 else 0 end) as ExecCount