对数据库之间的查询使用“Union All”

Question

我有一个有趣的情况，我想看看是否有解决方案...我在同一台服务器上的 4 个数据库中有 4 个表，所有表都具有相同的结构：

Pnl_IL_2012 数据库中的 dbo.IL_Membership Pnl_NM_2012 数据库中的 dbo.NM_Membership

我想将每个表中的聚合数据集组合成一个数据集，但我试图利用 (USE [Pnl_IL_2012] --> Go) 构造来尝试获取每个聚合查询的数据。

select * from 
(USE [Pnl_IL_2012]
GO
select 'IL' as PlanID, sum(Contracts_Hlth) as PROD_Contracts_Hlth from dbo.IL_Membership where [month] between '2012-09-01' and '2012-10-31') Q1

联合所有

select * from
(USE [Pnl_NM_2012]
GO
select 'NM' as PlanID, sum(Contracts_Hlth) as PROD_Contracts_Hlth from dbo.NM_Membership where [month] between '2012-09-01' and '2012-10-31') Q2

我收到以下错误：

Msg 156, Level 15, State 1, Line 2
Incorrect syntax near the keyword 'USE'.
Msg 102, Level 15, State 1, Line 1
Incorrect syntax near ')'.
Msg 156, Level 15, State 1, Line 5
Incorrect syntax near the keyword 'USE'.
Msg 102, Level 15, State 1, Line 1
Incorrect syntax near ')'.

谁有办法让 union all 跨数据库工作？我不需要加入只是一个工会......

Answer 1

GO 表示批处理结束，因此不能在查询中间使用。

改为使用three part name: 引用表格：

Pnl_IL_2012.dbo.IL_Membership

给你以下查询：

select 'IL' as PlanID, sum(Contracts_Hlth) as PROD_Contracts_Hlth 
from Pnl_IL_2012.dbo.IL_Membership 
where [month] between '2012-09-01' and '2012-10-31'

union all

select 'NM' as PlanID, sum(Contracts_Hlth) as PROD_Contracts_Hlth 
from Pnl_NM_2012.dbo.IL_Membership 
where [month] between '2012-09-01' and '2012-10-31'