我对 DB2 SQL 服务器非常不熟悉。我正在尝试从多个表中查询总 rowCount,如下所示:
SELECT
SUM(COUNT)
AS ROWS
FROM
(SELECT COUNT(*) AS COUNT FROM TABLE1
UNION ALL
SELECT COUNT(*) AS COUNT FROM TABLE2
UNION ALL
SELECT COUNT(*) AS COUNT FROM TABLE3
UNION ALL
//ETC...
)
但它一直在“)”上标记语法错误。我将如何重组它?
最佳答案
DB2(和 SQL Server)要求子查询具有别名,因此:
SELECT
SUM(COUNT)
AS ROWS
FROM
(SELECT COUNT(*) AS COUNT FROM TABLE1
UNION ALL
SELECT COUNT(*) AS COUNT FROM TABLE2
UNION ALL
SELECT COUNT(*) AS COUNT FROM TABLE3
UNION ALL
//ETC...
) as subqueryAlias
关于mysql - 将带有子查询的 mySQL 查询转换为带有子查询的 DB2 SQL 查询,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/28219623/