摘要： 子查询分两种，有关子查询和无关子查询。无关子查询很常用： SELECT TOP 5 * INTO #a FROM [AdventureWorks].[HumanResources].[Employee] SELECT TOP 8 * INTO #b FROM [AdventureWorks].[HumanResources].[Employee] SELECT * FROM #a WHERE EmployeeID not in (SELECT EmployeeID FROM #b) SELECT * FROM #b WHERE EmployeeID not in (SELECT Employe 阅读全文