The entities existing in the project can be exposed using the DbSet Property. Connect and share knowledge within a single location that is structured and easy to search. The Database Provider are a set of API that used to connect to a particular database. There are many different database Providers currently available with the EF Core.
Using multiple EF Core DbContexts in a single application is straightforward and has many benefits. If you decide to use different schemas per DbContext, you will be unpleasantly surprised to learn that the default schema doesn’t apply to the migrations history table. However, if you want to configure a different schema for each DbContext then you also need to override the OnModelCreating method and specify the custom schema with HasDefaultSchema.
How can you handle relationships between tables in Entity Framework?
If you just want to use both DbContexts in the same schema, then this is all the configuration you need. You can now inject the DbContext instances in your application and use them. If the application you’re building has a complex domain model, you may see an improvement by separating concerns between a few DbContexts, where each one is responsible for a specific area of the domain model.
These template files are responsible for generating the C# or VB.Net classes that represent the entities (tables) in your database. This code generation occurs during compile-time, whenever you save changes to the entity data model (.edmx file) or manually run the “Run Custom Tool” command. If you need to customize the generated code, you can edit these .tt template files.
What is Code First approach in Entity Framework and how does it work?
It returns a Collection of DbEntityValidationResult containing validation results. Find centralized, trusted content and collaborate around the technologies you use most. The optionsBuilder.IsConfigured returns a boolean value indicating whether any options have been configured.
Once we have a created context and the DbSets for the entities, we can then perform the CRUD operations on them. In order to use the DbContext class in our .NET Application, we need to create a class derives from the DbContext class. The DbContext class is present in Microsoft.EntityFrameworkCore namespace. The Entity Framework Core DbContext class includes a property, i.e., DbSet, for each entity in your application. Let us understand the need and use of DbContext Class with an example. At the root directory of your project, create a folder and name it as Entities.
These well-curated EF Core interview questions will certainly widen your knowledge base and also demonstrate how to explain intricate concepts in the simplest manner. There are a few cases where using multiple DbContexts can be useful. We hope that this EDUCBA information on “Entity Framework DbContext” was beneficial to you. The DbSet properties what is entity framework like CompanyTable and Orders will perform the entire operations. There is however a number of other issues you will run into with an injected DbContext regardless of the architectural style of your application. The answers here aren’t obvious and will require you to pour through your DI container configuration code to find out.
- By eliminating the need to load unnecessary related entities (as in explicit loading), lazy loading seems to relieve the developer from dealing with related entities entirely.
- A DbContext instance can however span across multiple (sequential) business transactions.
- After an async operation, you will most likely find yourself in another thread than the one where the DbContext was created.
- An obvious side-effect of manually controlling the database transaction scope is that you are now forcing the database connection and transaction to remain open for the duration of the transaction scope.
The following code snippet illustrates how you can use async code to update an entity in the database using EF Core. When you’re quering data in EF Core, use IQueryable instead of IEnumerable. When you use IQueryable, the SQL statements will be executed on the server side, where the data is stored, whereas IEnumerable requires the query to be executed on the client side. Moreover, while IQueryable supports query optimizations and lazy loading, IEnumerable does not.
The Remove method works for both existing and newly added entities. Calling Remove on an entity that has been added but not yet saved to the database will cancel the addition of the entity. The entity is removed from the change tracker and is no longer tracked by the DbContext object and in that case, there is no database interaction when we call the SaveChanges method. In the following example, the student is removed from the database whose id is 5. The following code is self-explained, so please go through the comment lines. In this article we examined 10 key strategies you can use to improve data access performance in EF Core.
