var a = from m in DbContext.Set<T1>() join q in DbContext.Set<T2>() on new { m.ID, Phone=m.Phone1 } equals new { q.ID, Phone=q.Phone2 } where m.Phone1 !=null select new { m.ID, m.Phone1 }; a = a.OrderBy(m => m.Phone1).Skip().Take(); SELECT
1. select * from a left join b on a.id = b.id and a.dt=20181115; 2. select * from a left join b on a.id = b.id and b.dt=20181115; 3. select * from a join b on a.id = b.id and a.dt=20181115; 4. select * from a left join b on a.id = b.id where a.dt=201
Linq Join Group by 时报Nullable object must have a value. 例如: from s in subject on ch.SubId equals s.SubId join gc in (from aq in question group aq by aq.ChapterId into gaq select new { Id = gaq.Key, Count = gaq.Count(), }) on s.QueId equals gc.Id into
还是习惯先撸一段SQL * FROM User_Pic P AND P.Guid = R.UserPicGuid ORDER BY PicSize DESC 然后发现Linq中的join不能多条件... 结果找到解决方案如下 ; var pic = (from p in db.User_Pic join r in db.R_User_Pic on new { _guid = p.Guid, _id = ID } equals new { _guid = r.UserPicGuid, _id =
1.sql语句: select * from Users u join Teachers t on u.UserID==t.TeacherID and u.Name=t.Name 2.linq写法: 1).方法一: 将多个字段的比较,new 一个对象进行比较: 注意:对象的属性名要保持一致: var userInfos = from u in db.Users join t in db.Teachers on new { u.UserID , u.Name } equals new { User
var haveChange = from newScore in newScoreList join oldScore in oldScoreList on new{newScore.ExamId,newScore.StudentId,newScore.Subject,newScore.ClassId} equals new{oldScore.ExamId,oldScore.StudentId,oldScore.Subject,oldScore.ClassId} where newScore.
MXS&Vincene ─╄OvЁ &0000022─╄OvЁ MXS&Vincene MXS&Vincene ─╄OvЁ:今天很残酷,明天更残酷,后天很美好,但是绝大部分人是死在明天晚上,只有那些真正的英雄才能见到后天的太阳. MXS&Vincene ─╄OvЁ:We're here to put a dent in the universe. Otherwise why else even be here? 正文>>>>>
在做搜索和排序的时候,往往是前台传过来的字符串做条件,参数的数量还不定,这就需要用拼sql语句一样拼linq语句.而linq语句又是强类型的,不能用字符串拼出来. 现在好了,有个开源的linq扩展方法类,支持用字符串拼linq语句. 以下是转载: LINQ (language integrated query) is one of the new features provided with VS 2008 and .NET 3.5. LINQ makes the concept of
单条件: var query = from person in people join pet in pets on person equals pet.Owner select new { OwnerName = person.FirstName, PetName = pet.Name }; 多条件: IEnumerable<string> query = from employee in employees join student in students on new { employe
建立一对多的表 company 和 employee company表 id name address 1baidu北京 2huawei深圳 3jingdong北京 4tengxun上海 employee表 id name company_id age 1wang11 28 2zhang22 22 3sun13 19 4zhao22 33 5li55 25 1 left join: SELECT * FROM compan
代码: using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Data; using System.Reflection; namespace TestConsole { public class Program { public static void Main(string[] args) { var classify_list = new List
数组是大学里经常拿来做算法练习的对象.一些经典算法非常有价值,考试.装逼.面试都十分有用.但现在是效率时代,编程讲究生产效率,利用LINQ,可以让程序猿避免写一些基本算法,把精力花在业务处理上. 下面以数组为例,展示一些常用LINQ操作. staticvoidMain(string[] args){int[] a ={1,2,3,4,5,6,7};int[] b ={4,5,6,7,8,9,10};int[] c ={1,2,3,3,4,1,2,4,6,1,6,5};// 交集var fuck
通过linq查询datatable数据集合满足条件的数据集 1.首先定义查询字段的变量,比方深度 string strDepth=查询深度的值: var dataRows = from datarow in dataTable(须要查询的datatable数据集).AsEnumerable() where string.Compare(datarow.Field<string>(
