一米阳光

摘要： 创建Sales表:CREATE TABLE [dbo].[Sales]( [OrderId] [char](10) PRIMARY KEY NOT NULL , [Quantity] [int] NULL, [OrderDate] [datetime] NULL, [Employee] [char](10) NULL )GO查询第一季度的销售总量:select Employee as '雇员', '第一季度' as '季度', Sum(Case when month(OrderDate) in (1, 2, 3) then Quantity... 阅读全文