即使延迟加载不能使用,也可以通过明确的调用来延迟加载相关实体 使用DBEntryEntity来完成 using (var context = new SchoolDBEntities()) { //Disable Lazy loading context.Configuration.LazyLoadingEnabled = false; var student = (from s in context.Students where s.StudentName == "Bill" sel…

延迟加载:延迟加载相关的数据 using (var ctx = new SchoolDBEntities()) { //Loading students only IList<Student> studList = ctx.Students.ToList<Student>(); Student std = studList[]; //Loads Student address for particular Student only (seperate SQL query) Stud…

延迟加载:延迟加载相关的数据 using (var ctx = new SchoolDBEntities()) { //Loading students only IList<Student> studList = ctx.Students.ToList<Student>(); Student std = studList[]; //Loads Student address for particular Student only (seperate SQL query) Stud…

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…

Student studentToDelete; . Get student from DB using (var ctx = new SchoolDBEntities()) { studentToDelete = ctx.Students.Where(s => s.StudentName == "Student1").FirstOrDefault<Student>(); } //Create new context for disconnected scenario…

Explicit Loading with DBContext Even with lazy loading disabled, it is still possible to lazily load related entities, but it must be done with an explicit call. Use the Load method of DBEntityEntry object to accomplish this. The following code expli…

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…

在使用Entity Framework加载关联实体时,可以有三种方式: 1.懒加载(lazy Loading); 2.贪婪加载(eager loading); 3.显示加载(explicit loading). EF默认使用的是懒加载(lazy Loading).一切由EF自动处理. 这种方式会导致应用程序多次连接数据库,这种情况推荐在数据量较大的情况下使用.当我们需要加载数据较少时,一次性全部加载数据会相对更高效. 我们来看看EF的显示加载(explicit loading)如何让我们完全掌控…

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…

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…