//DataTable以列分组 var result = from r in dt.AsEnumerable() group r by ), b = r.Field<) } into g select new { key = g.Key, count = g.Count() }; var s = result.ToList();
来源:https://codedefault.com/2018/group-by-multiple-columns-and-sum-in-csharp .NET[C#]LINQ按多列分组(Group By)并计算总和(Sum) SQL语句: SELECT * FROM <TableName> GROUP BY <Column1>,<Column2> QuantityBreakdown ( MaterialID int, ProductID int, Quantity f
DB2通过某列分组来去重,可防止distinct对大字段的去重报错. row_number() OVER (PARTITION BY COL1 ORDER BY COL2) 表示根据COL1分组,在分组内部根据 COL2排序,而此函数计算的值就表示每组内部排序后的顺序编号(组内连续的唯一的) SELECT *, Row_Number() OVER (partition by deptid ORDER BY salary desc) as aa rank FROM employee WHERE
People.cs using System;using System.Collections.Generic;using System.Data;using System.Linq;using System.Text; namespace RadGridViewControl{ public class People { public Guid Id { get; set; } public string FirstName { get; set; } public string LastNa
以前在开发的时候遇到过一个需求,就是要按照某一列进行分组后取前几条数据,今天又有同事碰到了,帮解决了之后顺便写一篇博客记录一下. 首先先建一个基础数据表,代码如下: IF OBJECT_ID(N'Test') IS NOT NULL BEGIN DROP TABLE Test END CREATE TABLE Test(ID bigint IDENTITY(1,1),Name nvarchar(50),Department nvarchar(50)) INSERT IN
直接上代码吧,原理可以看我上一篇博文.本实现基于jquery,完美实现拖动改变表格的列大小功能,只需将代码放置在你页面的底部即可(jquery必须先引入). $(function () { var isMouseDown = false; var currentTh = null; $('table th').bind({ mousedown:function (e) { var $th = $(this); var left = $th.offset().left; //元素距左 var ri
group by rollup() 按分组合计 select grouping(status),status,owner,object_type,count(*) from dba_objects where owner not in ('SYS','SYSTEM') group by rollup (status,owner,object_type) order by status,owner,object_type; 经典分类查询语句: select object_type,count(*)
不说明,直接看代码: --1. 创建表,添加测试数据 CREATE TABLE #test(code varchar(50), [values] varchar(10)) INSERT #test SELECT '001', 'aa' UNION ALL SELECT '001', 'bb' UNION ALL SELECT '002', 'aaa' UNION ALL SELECT '002', 'bbb' UNION ALL SELECT '002', 'ccc' ---2 查询SELECT
