SQL Linq lamda区别
SQL |
LINQ |
Lambda |
---|---|---|
SELECT * FROM HumanResources.Employee |
from e in Employees select e |
Employees |
SELECT e.LoginID, e.JobTitle FROM HumanResources.Employee AS e |
from e in Employees select new {e.LoginID, e.JobTitle} |
Employees |
SELECT e.LoginID AS ID, e.JobTitle AS Title FROM HumanResources.Employee AS e |
from e in Employees select new {ID = e.LoginID, Title = e.JobTitle} |
Employees |
SELECT DISTINCT e.JobTitle FROM HumanResources.Employee AS e |
(from e in Employees select e.JobTitle).Distinct() |
Employees |
SELECT e.* FROM HumanResources.Employee AS e WHERE e.LoginID = 'test' |
from e in Employees where e.LoginID == "test" select e |
Employees |
SELECT e.* FROM HumanResources.Employee AS e WHERE e.LoginID = 'test' AND e.SalariedFlag = 1 |
from e in Employees where e.LoginID == "test" && e.SalariedFlag select e |
Employees |
SELECT e.* WHERE e.VacationHours >= 2 AND e.VacationHours <= 10 |
from e in Employees where e.VacationHours >= 2 && e.VacationHours <= 10 select e |
Employees |
SELECT e.* FROM HumanResources.Employee AS e |
from e in Employees orderby e.NationalIDNumber select e |
Employees |
SELECT e.* FROM HumanResources.Employee AS e ORDER BY e.HireDate DESC, e.NationalIDNumber |
from e in Employees orderby e.HireDate descending, e.NationalIDNumber select e |
Employees |
SELECT e.* WHERE e.JobTitle LIKE 'Vice%' OR SUBSTRING(e.JobTitle, 0, 3) = 'Pro' |
from e in Employees where e.JobTitle.StartsWith("Vice") || e.JobTitle.Substring(0, 3) == "Pro" select e |
Employees |
SELECT SUM(e.VacationHours) FROM HumanResources.Employee AS e |
Employees.Sum(e => e.VacationHours); |
|
SELECT COUNT(*) FROM HumanResources.Employee AS e |
Employees.Count(); |
|
SELECT SUM(e.VacationHours) AS TotalVacations, e.JobTitle FROM HumanResources.Employee AS e GROUP BY e.JobTitle |
from e in Employees group e by e.JobTitle into g select new {JobTitle = g.Key, TotalVacations = g.Sum(e => e.VacationHours)} |
Employees |
SELECT e.JobTitle, SUM(e.VacationHours) AS TotalVacations FROM HumanResources.Employee AS e GROUP BY e.JobTitle HAVING e.COUNT(*) > 2 |
from e in Employees group e by e.JobTitle into g where g.Count() > 2 select new {JobTitle = g.Key, TotalVacations = g.Sum(e => e.VacationHours)} |
Employees |
SELECT * FROM Production.Product AS p, Production.ProductReview AS pr |
from p in Products from pr in ProductReviews select new {p, pr} |
Products |
SELECT * FROM Production.Product AS p INNER JOIN Production.ProductReview AS pr ON p.ProductID = pr.ProductID |
from p in Products join pr in ProductReviews on p.ProductID equals pr.ProductID select new {p, pr} |
Products |
SELECT * FROM Production.Product AS p INNER JOIN Production.ProductCostHistory AS pch ON p.ProductID = pch.ProductID AND p.SellStartDate = pch.StartDate |
from p in Products join pch in ProductCostHistories on new {p.ProductID, StartDate = p.SellStartDate} equals new {pch.ProductID, StartDate = pch.StartDate} select new {p, pch} |
Products |
SELECT * FROM Production.Product AS p LEFT OUTER JOIN Production.ProductReview AS pr ON p.ProductID = pr.ProductID |
from p in Products join pr in ProductReviews on p.ProductID equals pr.ProductID into prodrev select new {p, prodrev} |
Products |
SELECT p.ProductID AS ID FROM Production.Product AS p UNION SELECT pr.ProductReviewID FROM Production.ProductReview AS pr |
(from p in Products select new {ID = p.ProductID}).Union( from pr in ProductReviews select new {ID = pr.ProductReviewID}) |
Products |
SELECT TOP (10) * FROM Production.Product AS p WHERE p.StandardCost < 100 |
(from p in Products where p.StandardCost < 100 select p).Take(10) |
Products |
SELECT * FROM [Production].[Product] AS p WHERE p.ProductID IN( SELECT pr.ProductID FROM [Production].[ProductReview] AS [pr] WHERE pr.[Rating] = 5 ) |
from p in Products where (from pr in ProductReviews where pr.Rating == 5 select pr.ProductID).Contains(p.ProductID) select p |
Products |
SQL Linq lamda区别的更多相关文章
- SQL/LINQ/Lamda 写法[转发]
SQL LINQ Lambda SELECT * FROM HumanResources.Employee from e in Employees select e Employees .Sele ...
- SQL/LINQ/Lamda
SQL LINQ Lambda SELECT * FROM HumanResources.Employee from e in Employees select e Employees .Sele ...
- SQL,LINQ,Lambda语法对照图(转载)
如果你熟悉SQL语句,当使用LINQ时,会有似曾相识的感觉.但又略有不同.下面是SQL和LINQ,Lambda语法对照图 SQL LINQ Lambda SELECT * FROM HumanReso ...
- Oracle与Sql server的区别
一直搞不明白Oracle数据库和sql server的区别,今天我特意查资料把他们的区别整理出来 Oracle数据库:Oracle Database,又名Oracle RDBMS,或简称Oracle. ...
- Access、SQLServer、Oracle常见SQL语句应用区别
Access.SQLServer.Oracle常见SQL语句应用区别 关劲松 PMP 如果要兼容Access.SQL Server.Oracle三个数据库版本:我们在编写SQL语句的过程中,尽量使用一 ...
- sqlServer存储过程与sql语句的区别
sqlServer 存储过程与sql语句的区别 sql存储过程与sql语句的区别: 从以下几个方面考虑: 1.编写: 存储过程:编写比较难: sql语句:相对简单: 2.性能: 存储过程:高,可移 ...
- java.util.Date和java.sql.Date的区别和相互转化 (转)
java.util.Date和java.sql.Date的区别及应用 java.util.Date 就是在除了SQL语句的情况下面使用 java.sql.Date 是针对SQL语句使用的,它只包含 ...
- LINQ / LINQ to SQL / LINQ to XXX 它们到底有什么区别
LINQ是新生事物,不过从不少文章和讨论上看来,这方面的概念也已经有点混沌不清了.因此我们经常可以看到这样的话: LINQ只能将数据表与实体属性一一对应…… LINQ开发指南:在LINQ中进行数据库字 ...
- SQL,Linq,Lambda之间的转换练习
1.查询Student表中的所有记录的Sname.Ssex和Class列. SQL:select sname,ssex,class from Students linq:from s in Stude ...
随机推荐
- 在其他系统Iframe中显示SharePoint 页面
前段时间在做一个项目,要求将SharePoint 的 OWA(Office Web Apps)中的文档显示页面嵌入到另外一个OA系统中,提供给用户可以通过浏览器查看SharePoint文档的能力. 嵌 ...
- Android自定义控件4--优酷菜单的菜单键及细节补充
在上篇文章中实现了优酷菜单执行动画,本文接着完善已经实现的动画功能 本文地址:http://www.cnblogs.com/wuyudong/p/5915958.html ,转载请注明源地址. 已经实 ...
- Android 拍照后保证保证图片不失真,进行压缩
今天在网上找了一下参考,得出把图片压缩至KB 其他不想多说.直接上代码 拍完照后调用下面代码 BitmapUtils.compressBitmap(photoPath, photoPath, 640) ...
- Ubuntu14.04 Django Mysql安装部署全过程
Ubuntu14.04 Django Mysql安装部署全过程 一.简要步骤.(阿里云Ubuntu14.04) Python安装 Django Mysql的安装与配置 记录一下我的部署过程,也方便 ...
- iOS开发之Socket
在IOS开发中,网络请求链接往往是HTTP请求,但是有些需求比较特殊,需要保持持续连接,就需要用到Socket了. 另外在游戏开发中,常常会用到Socket连接,因为http请求数据往往需要用户主动请 ...
- 在UTF-8中,一个汉字为什么需要三个字节?
UNICODE是万能编码,包含了所有符号的编码,它规定了所有符号在计算机底层的二进制的表示顺序.有关Unicode为什么会出现就不叙述了,Unicode是针对所有计算机的使用者定义一套统一的编码规范, ...
- 关于Redis数据过期策略
1.Redis中key的的过期时间 通过EXPIRE key seconds命令来设置数据的过期时间.返回1表明设置成功,返回0表明key不存在或者不能成功设置过期时间.在key上设置了过期时间后ke ...
- HDFS Federation (读书笔记)
HDFS Federation (读书笔记) HDFS的架构 HDFS包含两个层次:命名空间管理(Namespace) 和 块/存储管理(Block Storage). 命名空间管理(Namespac ...
- Java环境变量的配置
1.JAVA_HOMEjdk的路径,我的是安装在C:\Program Files (x86)\Java\jdk1.6.0_182.CLASSPATH .;%JAVA_HOME%\lib\dt.jar; ...
- C++智能指针详解
本文出自http://mxdxm.iteye.com/ 一.简介 由于 C++ 语言没有自动内存回收机制,程序员每次 new 出来的内存都要手动 delete.程序员忘记 delete,流程太复杂,最 ...