摘要： 1、有以表结构如下id goodsid scount type6 3 40 out5 2 30 in4 1 45 out3 3 20 out2 2 20 in1 1 10 in要查询到如下结果goodsid 进货 出库 库存解：select goodsid,sum(a.sin) as aa,sum(a.sout) as bb ,sum(a.sin)-sum(a.sout)from(select id,goodsid, case type when 'in' then scount else '0' end as sin,case type when 'o 阅读全文

摘要： namespace ConsoleApplication2{ //最简单的委托的用法----------------------------------- //delegate void SayHello(string pString);//声明一个委托 //class Program //{ // static void Main(string[] args) // { // SayHello sh = EnglishHello; // sh("English"); // sh = new Program().ChineseHello; // sh("Chine 阅读全文