摘要：
using System;using System.Collections.Generic;using System.Text;using System.IO;using NPOI.SS.UserModel; //NPOIusing NPOI.HSSF.Util; //NPOIusing NPOI.HSSF.UserModel; //NPOIusing NPOI.XSSF.UserModel; //NPOIusing System.Data.SqlClient;using System.Data;请先下载NPOI的所有dll,然后Add r... 阅读全文
摘要：
SQLServer2005通过intersect,union,except和三个关键字对应交、并、差三种集合运算。他们的对应关系可以参考下面图示 相关测试实例如下：use tempdb go if(object_id('t1') is not null) drop table t1 if(object_id('t2') is not null) drop table t2 go create table t1 (a int) insert into t1 select 1 union select 2 union select 3 create table t2 阅读全文