EntityFramework Eagerly Loading Eager loading is the process whereby a query for one type of entity also loads related entities as part of the query. Eager loading is achieved by use of the Include method. For example, the queries below will load blo…

Entity Framework提供了三种加载相关实体的方法:Lazy Loading,Eager Loading和Explicit Loading.首先我们先来看一下MSDN对三种加载实体方法的定义. Lazy Loading:对于这种类型的加载,在您访问导航属性时,会从数据源自动加载相关实体. 使用此加载类型时,请注意,如果实体尚未在 ObjectContext 中,则您访问的每个导航属性都会导致针对数据源执行一个单独的查询. Eager Loading:当您了解应用程序需要的相关实体的图形…

Entity Framework Core allows you to use the navigation properties in your model to load related entities. There are three common O/RM patterns used to load related data. Eager loading means that the related data is loaded from the database as part of…

Eager Loading: Eager loading is the process whereby a query for one type of entity also loads related entities as part of the query. Eager loading is achieved using the Include() method. In the following example, it gets all the students from the dat…

贪婪加载是指查询一个类型实体的时候同时查询与实体关联的类型 通过Include()方法实现 using (var context = new SchoolDBEntities()) { var stud1 = (from s in context.Students.Include("Standard") where s.StudentName == "Student1" select s).FirstOrDefault<Student>(); } usi…

预先加载 在对一种类型的实体进行查询时,将相关的实体作为查询的一部分一起加载.预先加载可以使用Include()方法实现. 在此需要说明的是:EF中有两种表关联的方法,一种是Join()方法,一种是Include()方法 Join()方法使用说明:两表不必含有外键关系,需要代码手动指定连接外键相等(具有可拓展性,除了值相等,还能指定是>,<以及其他对两表的相应键的关系),以及结果字段. Include()方法说明:两表必须含有外键关系,只需要指定键名对应的类属性名即可,不需指定结果字段(即全部…

axios带有请求拦截器,避免在每个请求里面加loading重复操作,可以封装进去,在请求开始时加载loading层,请求结束关闭,loading层用vux的loading加载 axios.js import axios from 'axios' import Vue from 'vue' // 超时时间 axios.defaults.timeout = 15000; // axios.defaults.withCredentials=true; // http请求拦截器 axios.inter…

Introduction Lazy loading is a concept where we delay the loading of the object until the point where we need it. Putting in simple words, on demand object loading rather than loading objects unnecessarily. For example, consider the below example whe…

Performance Considerations for Entity Framework 5 By David Obando, Eric Dettinger and others Published: April 2012 1. Introduction Object-Relational Mapping frameworks are a convenient way to provide an abstraction for data access in an object-orient…

java设计模式大全 Design pattern samples in Java(最经典最全的资料) 2015年06月19日 13:10:58 阅读数:11100 Design pattern samples in Java. Build status: Introduction Design patterns are formalized best practices that the programmer can use to solve common problems when desi…