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linq to sql not in

T-SQL的 IN:Select ProductID, ProductName, CategoryIDFrom dbo.ProductsWhere CategoryID in (1, 2)T-SQL的 NOT IN:Select ProductID, ProductName, CategoryIDFrom dbo.ProductsWhere CategoryID not in (1, 2)//-------------------------...

select TOP 4*from Examine where ExamineLevel not in(select LinkLevel from Link where LinkClubId==3) --not in 把where条件改成不等于3就好啦 and ExamineTypeId not in(select LinkExamineTypeId from Link where LinkClubId==3 ) --not i...

假设有两个Textbox,分别为textbox1和textbox2,有个表,表名为list,里面有x列和y列 var a=from b in list where b.x==textbox1.Text.Trim()||string.IsNullOrEmpty(textbox1.Text.Trim()) &&(b.y==textbox2.Text.Trim()||string.IsNullOrEmpty(t...

StuDBDataContext db = new StuDBDataContext(); var query = stuInfo.Where(x => !StuMarks.Select(y => y.stuNo).Contains(x.stuNo)); //select * from stuInfo where stuNo not in(select stuNo from StuMarks) foreach (var c in result) { ...

需要查询数据表TableA 中字段Age(int)的值在一个给定集合中的纪录 用Sql 表示就是 Select * from TableA where Code in ('A','B','C') 那么如何使用 Linq to Entity 来实现此操作 List codeSet=new List{“A”,"B","C"} using(DBContext context=n...

StuDBDataContext db = new StuDBDataContext(); var query = stuInfo.Where(x => !StuMarks.Select(y => y.stuNo).Contains(x.stuNo)); //select * from stuInfo where stuNo not in(select stuNo from StuMarks) foreach (var c in result) { ...

LINQ to SQL和Entity Framework都是一种包含LINQ功能的对象关系映射技术。他们之间的本质区别在于EF对数据库架构和查询的类型实行了更好的解耦。使用EF,查询的对象不再是完全对应数据库架构的C#类,而是更高层的抽象:Entity Data Model。这提...

参考代码(注意黑色部分)using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Xml; using System.Net; using System.IO; using System.Data; using System.Reflection; using System.Collect...

用Contains()方法; 首先获取t2.id这个对象 假如这个id=2 假如表是User var item=from u in ctx.user where u.id=2; 再判断 bool isexists= ctx.user.Contains(item);

例子: -- SQL --DECLARE @p1 NVarChar(8); DECLARE @p0 NVarChar(7); Select @p1 = 'Johnson'; Select @p0 = 'Anderson'; -- Context: SqlProvider(Sql2005) Model: AttributedMetaModel Build: 3.5.21022.8 SELECT [t0].[Id], [t0].[FirstName...

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