如何在不同的数据库中解析SQL Server数据

SELECT 'T2',* FROM Test_Cross_2.dbo.Orders_2
LEFT OUTER JOIN Test_Cross_1.dbo.Orders_1

ON Test_Cross_2.dbo.Orders_2.OrderNo = Test_Cross_1.dbo.Orders_1.OrderNumber

WHERE OrderNumberISNULL
UNION

SELECT 'T1',* FROM Test_Cross_1.dbo.Orders_1
LEFT OUTER JOIN Test_Cross_2.dbo.Orders_2

ON Test_Cross_1.dbo.Orders_1.OrderNumber = Test_Cross_2.dbo.Orders_2.OrderNo

WHERE OrderNo IS NULL