What Is DbContext C#?

Should DbContext be Singleton?

Singleton-scope is a very bad idea for your context.

Assuming that the entities you’re utilizing all originate from the same context type, and that you’re properly injecting the context everywhere it’s needed, there should never be multiple context instances in play..

Why is Linq bad?

LINQ works great in most cases, but when you want to build complex queries (e.g. in reporting apps) it’s statically-typed nature becomes a disadvantage. It’s hard to, for instance, conditionally JOIN, or conditionally GROUP BY, because the result type changes, even if in the end you want to project the same fields.

What is scaffold DbContext?

Reverse engineering is the process of scaffolding entity type classes and a DbContext class based on a database schema. It can be performed using the Scaffold-DbContext command of the EF Core Package Manager Console (PMC) tools or the dotnet ef dbcontext scaffold command of the . NET Command-line Interface (CLI) tools.

What is Entity C#?

An entity in a broader setting is just a “something” that exists. In the C# ECMA an entity is a placeholder for something that you refer to. This could be a an instance if you refer to an entity created from a class.

What is DbSet in C#?

A DbSet represents the collection of all entities in the context, or that can be queried from the database, of a given type. DbSet objects are created from a DbContext using the DbContext. Set method.

Is Linq faster than SQL?

We can see right away that LINQ is a lot slower than raw SQL, but compiled LINQ is a bit faster. Note that results are in microseconds; real-world queries may take tens or even hundreds of milliseconds, so LINQ overhead will be hardly noticeable. … Why compiled LINQ is faster than raw SQL?

Do we need to dispose DbContext?

Don’t dispose DbContext objects. DbContext manages its own lifetime; when your data access request is completed, DbContext will automatically close the database connection for you.

Is EF thread safe?

Entity Framework is not thread-safe. An MVC controller is instantiated per request. Thus if you use one DbContext per request, you’re safe as long as you don’t manually spawn threads in your controller actions (which you shouldn’t do anyway).

How can add DbContext in ASP NET MVC?

In this tutorial, you:Create an MVC web app.Set up the site style.Install Entity Framework 6.Create the data model.Create the database context.Initialize DB with test data.Set up EF 6 to use LocalDB.Create controller and views.More items…•

Does DbContext inherit ObjectContext?

DbContext is conceptually similar to ObjectContext. DbContext is nothing but a ObjectContext wrapper, we can say it is a lightweight alternative to the ObjectContext. DbContext can be used for DataBase first, code first and model first development. DbContext mainly contains a set of APIs that are very easy to use.

Is DbContext thread safe?

DbContext is not thread-safe You must never access your DbContext -derived instance from multiple threads simultaneously. … In a multi-threaded application, you must create and use a separate instance of your DbContext -derived class in each thread.

Which is faster Linq or Lambda?

In some cases LINQ is just as fast if not faster than other methods, but in other cases it can be slower. … There is no performance difference between LINQ queries and Lambda expressions. You should completely understand how LINQ feature(both Lambda, LINQ queries) works in .

Should I use LINQ to SQL?

More importantly: when it comes to querying databases, LINQ is in most cases a significantly more productive querying language than SQL. Compared to SQL, LINQ is simpler, tidier, and higher-level. … Here’s same query in LINQ.

What is ado net in C#?

ADO.NET is a set of classes that expose data access services for . NET Framework programmers. ADO.NET provides a rich set of components for creating distributed, data-sharing applications. It is an integral part of the . NET Framework, providing access to relational, XML, and application data.

What is DbContext C#?

A DbContext instance represents a combination of the Unit Of Work and Repository patterns such that it can be used to query from a database and group together changes that will then be written back to the store as a unit. DbContext is conceptually similar to ObjectContext.