entity framework core include parent

ADO.NET Entity Framework and LINQ to Entities https: . Addition after comment Issue: EF7 may not be lazy-loading all entities in a graph of related entities, despite all entities' navigation properties being virtual: I built a basic blog atop EF6. You can also let Entity Framework Core generate code from an existing database using Reverse Engineering. Its use is described in the example below: declare @parent hierarchyid SET @parent = CAST ('/3/1/' AS hierarchyid); select [Name] , [Level].ToString () as [Level] from [dbo]. Let the query in the stored proc add the necessary "relationship" columns and populate them. Limitations. When I do a LINQ to Entities query for a specific Item, it doesn't return the related Category, unless I use the Include("Category") method. NET Core you can use the keyword ThenInclude : If you include the library System.Data.Entity you can use an overload of the Include method which takes a lambda expression instead of a string. The HierarchyId data type was introduced with SQL Server 2008. I created the tables using the entity framework tooling. Since Entity Framework Core is eager loading related data is not returned by default. So basically, the . Fastest Entity Framework Extensions . 2. Some design ideas work others don't. I create simple versions of the database models that do not include the reference to the parent class. An entity with a foreign key is the child or dependent entity in the relationship. Relationships in an Entity Framework Core (EF Core) model are represented using foreign keys (FKs). asp.net-core c# entity-framework-core. in this particular case total 7 SQL queries. . Furthermore, the Student and Subject classes both have navigational ICollection properties towards the StudentSubject class. I would like to create an entity that knows its parent, as well as all of its children. Question. I am reading a tutorial regarding Entity framework link .And it describes an action method for creating Instrcutor & selecting his related courses on the same screen. The usability is not ideal but acceptable. Is there a way (maybe using Expressions) to load a hierarchy of entities (i.e. Open the solution in Visual Studio, right-click on the Google.Cloud.EntityFrameworkCore.Spanner project and click on Pack . Specifies related entities to include in the query results. I would suggest you a hybrid approach (similar to the way EF Core processes the Includes) which will execute 1 SQL per parents, 1 per children and 1 per each grandchildren type, i.e. Accept Solution Reject Solution. When Entity Framework generated the model, the nested types just disappeared. Here is my entity: No future logic is required. Entity Framework Core (EF Core) represents relationships using foreign keys. In the unlikely case we don't know what we're talking about: a circular reference happens when an object has one or more properties referencing one or more objects, which in turn contain one or more properties referencing other objects (and so on) that ultimately reference the first one or a "parent" one, thus resulting in a closed loop.. Here's a diagram that visually shows a . We want to establish a one-to-many relationship where many students are associated with one grade. 881. Here, you will learn the new features . . This can be achieved by including a reference navigation property in the dependent entity as shown below. Now, we need to configure the other end of the . Learn how to create a NativeScript app using Angular. Querying in Entity Framework Core. . Tree operation extension methods below and helper interface for wrapping any entity into the tree node object. I was recently helping another developer understand the various "OnDelete" behaviors of Entity Framework Core. Prerequisites. Person is another entity, contains BirthDate and FatherName properties. Entity Framework Include Parent Entities. I Create two models with a optional One-to-One relationship, generate data and when I want to get the Parent model with the Child data using the INCLUDE method I have a infinite nested structure. This section covers few articles in C#. Precisely you have an Independent One-to-Many Self Reference Association that also has a custom name for the foreign key column (People.Parent). This is the very basics, in the future posts we will explore other options . To include the Invoice table, we use the Include method and passing the navigation property name as the lambda expression as shown below Include(c => c.Invoice).Note that the Invoice property is a collection navigational property in the customer entity.. You can look at the SQL query. Entity Framework Core EF Core Home EF Core 5 Articles Knowledge Base Online Examples EF Core 6.0 currently targets .NET 5. We should also have an Entity Framework Core context that exposes them: . entity-framework - I'm trying to load two children from a nested parent. Btw I'd like to keep this with the entity framework syntax only and rather not deal with linq and IQueryable because I'm trying to deal only with entities and wouldn't like to map things in the repository. Permalink. . Yes, lazy loading will generate a new trip to the database server to retrieve the child objects you want … and that's too bad. Loading Related Data, You can then Select() over children with Linq expressions rather than string paths . Here is how it supposed to get done . The key here is that I'm using conventions to tell EF that there is a parent-child relations. So I wrote a Get-method that does it for me:. EF Core 2.1: Self-referencing entity with one to many relationship generates additional column. how to annotate a parent-child relationship with Code-First. Nevertheless, you can use TPT with the current version of EF Core. EF Core using navigation property when querying parent and child separatedly c# entity-framework-core. I have used EF6 for the code in this article, but it's applicable to all Code First versions. This dependent/child entity is associated with a given principal/parent entity when the values of the foreign . The Entity Framework Core team has released the generally available version of EF Core 6.0 in parallel with .NET 6.EF Core 6 is available as a set of NuGet Packages.At the end of this blog post you will find a packages section that lists all of the available packages and describes what they are used for.. EF Core 6.0 is a modern, cloud-native-friendly data access API that supports multiple . START LEARNING. In Entity Framework Core, we have to create a joining entity for a joining table (StudentSubject). Nexus23. In my .NET Core / EF Core application I have a model with a nested list of child objects. extension method to return a collection of objects that have a child, where some of the children will be null.. We have a table Projects with a C# model Project and a table Locations with a C# model Location.. Each Project has a one or zero Location objects and the objects look like this: modelBuilder.Entity<Order> () .HasMany (o => o.OrderItems) .WithOptional () .HasForeignKey (oi => oi.OrderId) Next define composite key for OrderItem using anonymous object. C#. Entity Framework knows your one-to-many and understands that your use of the ICollection should result in an inner join followed by a Group By. Let's take a look at a simple example in which we have our basic model with three entities Student, Course and Enrollment. In document databases, the default behavior for entity types is to assume they are embedded documents owned by the parent. Eager Loading in Entity Framework. When I use Include method in a entity that have a One-to-one relationship with another one, I get a infinite nested structure. The most recent major version of Entity Framework is Entity Framework 6. Then, .HasOne< Grade >(s => s.Grade) specifies that the Student entity includes a Grade type property named Grade. So technically your entity can be any class where you have relation parent->children (to get the plain list of nodes from tree using Flatten) and child-> parent (to build the tree from the list . Entity Framework Core not loading related data from reference table. This is a step by step guide to learn Entity Framework Core Tutorial or EF Core Tutorial. I have an Item.Item has a Category.. Category has ID, Name, Parent and Children.Parent and Children are of Category too.. This release includes new attributes, built-in functions, and database-specific improvements to SQLite and SQL Server capabilities. Eager loading causes Entity Framework to retrieve the parents and child objects with one trip to the database server. Summarized: if you think you'll need a join in entity framework, think twice, you'll probably be able to do it simpler by using the ICollection or the reference to the parent. All you need is a single Include and then the EF navigation property fixup will do the work for you. NET Core you can use the keyword ThenInclude : If you include the library System.Data.Entity you can use an overload of the Include method which takes a lambda expression instead of a string. The Primary Key for the Parent is an Identity. Principal entity: This is the entity that contains the primary/alternate key properties. The EF Core Left Joins the Invoice table to customer table correctly using the CustomerId as join condition. This means each time related data is required Include or ThenInclude must be used as shown below. I have been experimenting with creating a website that leverages MVC with JSON for my presentation layer and Entity framework for data model/database. The support of Table-per-Type is in the backlog of the Entity Framework team, i.e. dbContext. The steps for configuring many-to-many relationships would the following: The Cloud Spanner Entity Framework Core provider supports database migrations. (here, the Student entity is the dependent entity and the Grade entity is the principal entity). Include parent and child in query? We must create a joining entity class for a joining table. This reduces the number of trips (at the cost of retrieving more data, of course). Text version of the videohttp://csharp-video-tutorials.blogspot.com/2014/06/part-22-many-to-many-relationship-in.htmlHealthy diet is very important both for . With the old string include syntax it was difficult to preload the right relationship. 1 _context.Parent .Include(d => d.OtherProperty) .Include(d => d.Children) .Include(d => d.Children.Select(dd=>dd.OtherProperty) .Include(d => d.Children.Select . These view models each have method to return the Database Version and a constructor that . Entity Framework Core marks the removed child entity as Modified instead of Deleted (it will mark it as Deleted later, during the execution of the SaveChanges() method, once the foreign key . This article is a beginner-level look at the topic of accessing related entities using the Entity Framework (EF). Also configure Id column values to be auto-generated by database, because it does not generate . There are three common O/RM patterns used to load related data. The previous implementations of Entity Framework, prior to version 6 and Core, were not exactly a full implementation of the Repository and Unit of Work pattern. Eager loading is achieved using the Include () method. In previous versions of EF Core, this behavior had to be configured explicitly for it to work with the Azure Cosmos DB provider. Ask Question Asked 6 years, 3 months ago. Include has performance impact when you are including a navigation property that is a collection because the parent information is repeated for that records found in hte collection. (whether or not you used DbSet . You need to drop down to fluent API to achieve your desired schema (Data annotations wouldn't do it). Today, the Entity Framework Core team announces the first preview release of EF Core 6.0. . Ask Question Asked 11 years, . I thought this was actually all fairly straight forward. The EF Core Left Joins the Invoice table to customer table correctly using the CustomerId as join condition. Thanks to help. returns possibly one record, if it exists in the database for the given primary key of the Parent entity. Querying in Entity Framework Core remains the same as in EF 6.x, with more optimized SQL queries and the ability to include C#/VB.NET functions into LINQ-to-Entities queries. Entity Framework is a very popular choice for .NET developers as an object-relation mapping (ORM) tool to access the data layer in .NET Code. For all child categories the ParentId field is used as to represent its parent's primary key value. This will likely be updated to .NET 6 as we near the release. The post includes a running example of how to configure a self reference entity with Code First. Entity Framework Core allows you to use the navigation properties in your model to load related entities. . Visit the LINQ-to-Entities chapter to learn more about the basics of querying in Entity Framework. EF Core 5.0 introduces the ToQueryString extension method, which will return the SQL that EF Core will generate when executing a LINQ query. Cascade delete automatically deletes the child row when the related parent row is deleted. NativeScript. for example context.Person.Include("Child").Where("it.ParentID is null"); . In the following example, it gets all the students from the . The way I understood things was : DeleteBehavior.Cascade - Delete the child when […] current entity, its parent, its grandparent its great grandparent etc . An FK consists of one or more properties on the dependent or child entity in the relationship. Sometimes referred to as the 'parent' of the relationship. Follow this example to generate the data model using Migrations with the data model being the source of truth. This entity's foreign key value must match the primary key value (or an alternate key value) of the related principal/parent entity. 580. Querying in Entity Framework Core remains the same as in EF 6.x, with more optimized SQL queries and the ability to include C#/VB.NET functions into LINQ-to-Entities queries. Eager loading means that the related data is loaded from the database as part of the initial query. Take a look at Managing Schemas for further details. It is fully supported by Microsoft on the .NET Core platform, but all new development should be done on Entity Framework Core. Entity Framework defaults to lazy loading and allows you to override it when necessary. Active 6 years, 3 months ago. . In Entity Framework Core we can have recursive entities. Entity Framework Core. First of all configure foreign key relationship between Order and OrderItem. Entity Framework Core made it easy to configure relationships using Fluent API. 4. Entity Framework - Include Multiple Levels of Properties. To include the Invoice table, we use the Include method and passing the navigation property name as the lambda expression as shown below Include(c => c.Invoice).Note that the Invoice property is a collection navigational property in the customer entity.. You can look at the SQL query. All software goes through evolutionary process. If you need to keep the column called "Parent" then the correct way to specify the mapping so that "Parent" is used as the FK in the database would be this: modelBuilder.Entity<Person> ().HasOptional (p => p.Parent).WithMany (p => p.Children).IsIndependent ().Map (m => m.MapKey (p => p.Id, "Parent")); However, there is a bug in CTP5 . Only the parent query result is stored into variable, the children and grandchildren queries are just executed, and . Question is how can we query these interdependent relationships if we have to include entity A in B's query and vice versa? Use a C# attribute to indicate that an entity has no key An entity type can now be configured as having no key using the new KeylessAttribute . This is the method of checking if the current node is a child of a given element. Repository https://bitbucket.org/Altair_CA/.net-core-entity-framework-self-referencing-tableNET CORE Entity Framework - Self Referencing TableTree StructureR. same thing not working with Not working with entity framework core: Tried something bellow. This is a simple tutorial for beginners to professionals to learn all the features of the Entity Framework. The navigation property to be included is specified starting with the type of entity being queried (TEntity). This class contains the foreign keys and navigational properties from the Student and Subject classes. (repeat is in query only) Steps to reproduce. the Post create action met. So technically your entity can be any class where you have relation parent->children (to get the plain list of nodes from the tree using Flatten) and child-> parent (to build the tree from the list using ToTree method): Explicit loading means that the related data is explicitly loaded from the . Include in Entity Framework 4.1. When I retrieve an instance, I need the nested list to be ordered by one of the child's properties. Visit the LINQ-to-Entities chapter to learn more about the basics of querying in Entity Framework. The Child also has a One to Many relationship with a ChildSpecification Entity. It is for people new to the entity framework, whether experienced or not as developers generally. We have a Parent Child relationship where the Parent has many Children as well as One or Zero Special Children. Notice how the id names used between the two entities match up. This code retrieves the Orders with the Customer objects by using the Include keyword: Text version of the videohttp://csharp-video-tutorials.blogspot.com/2014/06/part-17-self-referencing-association-in_3.htmlHealthy diet is very important both. It's most useful in WHERE Clauses. Values of this type are stored in a binary form, for example, 0x5AC0 or . However, lazy loading will avoid retrieving child objects you don't need when you retrieve the parents. Viewed 4k times 0 When I am accessing all cities my code is like this. This includes the server-side implementation of OData version 4 for ASP.NET Core. Entity Framework Core configures one to one relationships by being able to detect the foreign key property, and thereby identify which is the principal and which is the dependent entity in the relationship. For . That is, when a parent entity in a parent/child relationship is deleted, what should happen to the child? First, this is my RecursiveEntity<T> base-class:. Hierarchical data contain the notion of parent/child but also the notion of order between elements having the same parent. 0. Why Entity Framework Core is an Implementation of the Unit Of Work and Repository Pattern. . Either use a tracking query or remove the cycle. The joining entity for the above Student and Course entities should include a foreign key property and a reference navigation property for each entity. Introduction. If we have 40 leafs in the tree . public class Entity : IEntity { [Key] public int Id { get; set; } } public abstract class RecursiveEntity<TEntity> : Entity, IRecursiveEntity<TEntity> where TEntity . Let's add a property Identity, which is a Person type. Eager loading is the process whereby a query for one type of entity also loads related entities as part of the query, so that we don't need to execute a separate query for related entities. But it doesn't bring the full category, with its parent and children. Entity Framework Core Plus Query IncludeFilter Description. Entity Framework already does all the job by linking related entities to the parent. Principal key: . Still, this kind of loading come with a price. In Entity Framework Core, this has not been implemented yet. . Entity Framework 5 Updating a Record. Also noticed the foreign key constraint in the child. I have an "account" table that includes a string foreign-key ("parent_guid") to it's "parent" account (if one exists). With Entity Framework, "Include" method is often used to load related entities / child collections. Overview of foreign keys and navigations. I have two entities with one to many relationship like this: . To load related data Entity Framework Core has the .Include extension method. But we cannot do an "Include" for these recursives (can we?). This type is used to represent and manipulate hierarchical data. Let the database do the work. it is not (officially) supported yet. . START LEARNING. At that point, your child objects should have a reference to the parent. How can I load the Parent (level 1) whit all associated children (level 2) and for each child, associated grandchild (level 3) if any? In the current , 3.0 version of the Ef Core I started to get the following exception: System.InvalidOperationException : The Include path 'Category->Questions' results in a cycle. Hello, I get an Exception in EF Core 5 Table when I use: Table Valued Functions : InvalidOperationException: Unable to translate collection subquery in projection since the parent query doesn't project key columns of all of it's tables which are required to generate results on client side.This can happen when trying to correlate on keyless entity or when using 'Distinct' or 'GroupBy . In other words, the complex type's data exists within the context of the parent. Using Self Referencing Tables With Entity Framework. Clone the dotnet-spanner-entity-framework repository to your local system. I then rewrote this basic blog atop EF7. The ability to configure many-to-many relationships was introduced in EF Core 5.0, for previous version use the following approach. The Entity Framework Core 2.x (EF Core) officially supports the Table-per-Hierarchy pattern only. Entity Framework Core Parent/Child Clean query with multi level child. This entity may have 3 level: Parent -> Child -> Grandchild. EF - Include With Where Clause | Test your C# code online with .NET Fiddle code editor. Solution 1. The issue is when you remove a child ENTITY from a collection in a parent ENTITY and the child ENTITY has another relationship with a third ENTITY. I understand from reviewing similar questions and reported issues on EF Core that I can't order the nested list on retrieving the instance. I had a parent table that was referencing the same child table twice. This has the advantage to remove every mapping since the object is loaded itself by entity framework. If you wish to include additional types based on the navigation properties of the type being included, then chain a call to ThenInclude<TEntity,TPreviousProperty,TProperty>(IIncludableQueryable<TEntity,IEnumerable . . Entity framework core include child. Convention 1. Create a stored proc and call it from EF to populate the colle ction. If it is unable to do this, either because the foreign key property name does not follow convention, or because it has not been included in . . Entity framework core include child. Here, you will learn the new features . Querying in Entity Framework Core. Entity framework linq query Include() multiple children entities. It behaves as expected and correctly models many-to-many relationships - in this case, the fact that posts may have zero or more authors. . 13. The child has a ParentId that matches ParentId in its parent. Loading Related Data, You can then Select() over children with Linq expressions rather than string paths . Our goal is to query a database, using Entity Framework Core and the .Include(.) Cycles are not allowed in no-tracking queries. These view models each have method to return the database models that do not the....Net 6 as we near the release Framework Core generate code from an existing database using Reverse Engineering type... Form, for previous version use the following example, it gets all the students from the Student and classes. Can we? ) the relationship HierarchyId data type was introduced with SQL Server.. The students from the Student and Subject classes constraint in the relationship //entityframeworkcore.com/knowledge-base/40854591/include-parent-and-child-in-query- '' > to! The dependent entity as shown below children with Linq expressions rather than string paths had! The id names used between the two entities match up Managing Schemas for details! A price table that was referencing the same parent relationship is deleted, a. Solution in Visual Studio, right-click on the.NET Core platform, but all new development should done! The Solution in Visual Studio, right-click on the.NET Core platform, but new..., right-click on the Google.Cloud.EntityFrameworkCore.Spanner project and click on Pack retrieving child you! Exists within the context of the initial query type was introduced in EF Core Left Joins Invoice... In previous versions of EF Core ) model are represented using foreign keys ( FKs.! Stored proc add the necessary & quot ; columns and populate them be as! The cost of entity framework core include parent more data, you can then Select ( over! > Introduction Identity, which is a beginner-level look at the cost of retrieving more data, can. The.Include extension method fully supported by Microsoft on the Google.Cloud.EntityFrameworkCore.Spanner project and click on Pack, what should to. & quot ; Include & quot ; for these recursives ( can we )... Data is loaded from the have zero or more authors thing not working with not with. Query in the stored proc add the necessary & quot ; Include & ;... Cost of retrieving more data, you can use TPT with the data model using Migrations the... From reference table entity and the grade entity is the child row when the of... Model being the source of truth Forms tips and tricks... < /a > entity Core... Includes new attributes, built-in functions, and be used as shown below attributes, built-in functions and... Great grandparent etc with recursive with... < /a > Solution 1,. Core/Windows Forms tips and tricks... < /a > entity Framework is entity Framework has! To generate the data model using Migrations with the type of entity Framework.! Add a property Identity, which is a Person type if it exists in the.! Basics, in the relationship classes both have navigational ICollection properties towards the StudentSubject class OData version 4 for Core! Knows its parent and children loading come with a ChildSpecification entity proc the. Key of the relationship Framework tooling the necessary & quot ; columns and populate them Core Tutorial EF! Order between elements having the same child table twice to be configured for. Independent One-to-Many Self reference Association that also has a one to many relationship with ChildSpecification... Include or ThenInclude must be used as shown below in query we? ) step! Category, with its parent and children stored in a binary form, for example, or. Ability to configure many-to-many relationships - in this article is a step by step guide to entity... Starting with the old string Include syntax it was difficult to preload the right relationship Microsoft the! Entities with one to many relationship generates additional column additional column be used as shown below a... The Solution in Visual Studio, right-click on the dependent entity and the grade entity is the very,... Type is used as shown below the grade entity framework core include parent is the very basics, in the database part! Initial query data type was introduced in EF Core Tutorial or EF Core Tutorial or Core. Entities to the parent a stored proc add the necessary & quot ; Include quot... > Convention 1 in entity Framework Core - Inheritance - Table-per-Type ( TPT... < /a > Framework. Between elements having the same parent this case, the children and grandchildren queries just... Is entity Framework Core - Inheritance - Table-per-Type ( TPT... < /a Convention. That knows its parent & # x27 ; s primary key value s exists! Property in the database as part of the relationship me: the Google.Cloud.EntityFrameworkCore.Spanner project and click on Pack Linq..Net Core platform, but all new development should be done on entity (! ( ) method when i am accessing all cities my code is this! More properties on the.NET Core platform, but all new development should be done on entity Core... Related data, of course ) this means each time related data of! Likely be updated to.NET 6 as we near the release using expressions ) load...: //www.thinktecture.com/en/entity-framework-core/table-per-type-inheritance-support-part-1-code-first/ '' > entity Framework Core generate code from an existing database Reverse. - Table-per-Type ( TPT... < /a > entity Framework Core generate code an! And course entities should Include a foreign key property and a reference to the child are represented using foreign (. As all of its children have used EF6 for the above Student and Subject classes achieved including! Convention 1 Select ( ) over children with Linq expressions rather than string paths hierarchical structure recursive! 4K times 0 when i am accessing all cities my code is like this not loading related,... Come with a ChildSpecification entity be used as to represent its parent, its parent & # x27 s!: //www.tektutorialshub.com/ '' > Home - TekTutorialsHub < /a > Convention 1 models many-to-many relationships - in this case the... Referencing the same child table twice let entity Framework team, i.e relationship. The source of truth create an entity with a foreign key property and a reference navigation property for each.. Add the necessary & quot ; Include & quot ; for these recursives ( can we? ) may. But all new development should be done on entity Framework ; s data exists within the context of.! Context of the parent with SQL Server capabilities from the done on entity Framework ( EF 2.1! These recursives ( can we? ) loaded from the it from EF to populate colle... Number of trips ( at the topic of accessing related entities using the CustomerId as join condition should to. Convention 1 table that was referencing the same child table twice ) model are represented using keys! Grade entity is associated with one to many relationship generates additional column when... One to many relationship like this: previous version use the following example, 0x5AC0 or as to its. Ability to configure many-to-many relationships - in this article is a beginner-level look at Managing Schemas for further details (... - Inheritance - Table-per-Type ( TPT... < /a > Convention 1 and populate them but it doesn #... Id column values to be configured explicitly for it to work with the current version EF! That also has a one to many relationship like this: many relationship with a price class a. This case, the children and grandchildren queries are just executed, and as near. Only the parent query result is stored into variable, the children and grandchildren queries are just executed, database-specific. Automatically deletes the child or dependent entity as shown below this: populate them has ParentId..., your child objects you don & # x27 ; s primary key of the entity Framework has... Difficult to preload the right relationship Microsoft on the dependent entity in the child future posts will! To work with the current version of entity being queried ( TEntity ) Include syntax it was difficult to the! Table correctly using the entity Framework Core type are stored in a parent/child relationship is deleted proc call... Above Student and Subject classes of truth are associated with a price previous versions of parent. It doesn & # x27 ; t & gt ; base-class: a! Team, i.e child has a one to many relationship like this: improvements SQLite... The topic of accessing related entities / child collections of this type is as. Its children FK consists of one or more authors the children and grandchildren queries just! Theninclude must be used as shown below implementation of OData version 4 for ASP.NET Core avoid child... First, this is my RecursiveEntity & lt ; t need when you the... Maybe using expressions ) to load related data achieved using the entity Framework Core has advantage... Classes both have navigational ICollection properties towards the StudentSubject class as developers generally to populate the colle.! Wrote a Get-method that does it for me: the.Include extension.! Also noticed the foreign key is the principal entity ) Core parent/child Clean query with multi level.... Identity, which is a Person type proc add the necessary & quot relationship. With not working with entity Framework to SQLite and SQL Server capabilities recent major of! A constructor that Framework team, i.e Azure Cosmos DB provider form, for previous version use following., it gets all the job by linking related entities using the entity Framework is entity Framework Core ( Core. Dependent or child entity in the relationship Core - Inheritance - Table-per-Type ( TPT... < /a entity... Child in query hierarchy of entities ( i.e //www.entityframeworktutorial.net/eager-loading-in-entity-framework.aspx '' > eager loading is achieved using CustomerId... Not as developers generally when i am accessing all cities my code is this... ( TEntity ) gets all the job by linking related entities using the Framework.