Should a repository return IQueryable?

Should a repository return IQueryable?

If they add a where clause to a deferred IQueryable , you only have to send that data over the wire, not the entire result set. If you are using repository pattern – no, you should not return IQueryable.

Is repository pattern needed with Entity Framework?

No, the repository/unit-of-work pattern (shortened to Rep/UoW) isn’t useful with EF Core. A better solution is to use EF Core directly, which allows you to use all of EF Core’s feature to produce high-performing database accesses.

When should you use repository pattern?

The Repository pattern makes it easier to test your application logic. The Repository pattern allows you to easily test your application with unit tests. Remember that unit tests only test your code, not infrastructure, so the repository abstractions make it easier to achieve that goal.

Should I use IQueryable?

IQueryable uses Expression objects that result in the query being executed only when the application requests an enumeration. Use IQueryable when you have to run ad-hoc queries against data source like LinQ to SQL Server,Entity framework and other sources which implement IQueryable.

What is IQueryable C#?

IQueryable exists in the System. Linq Namespace. IQueryable is suitable for querying data from out-memory (like remote database, service) collections. While querying data from a database, IQueryable executes a “select query” on server-side with all filters. IQueryable is beneficial for LINQ to SQL queries.

What is AsQueryable C#?

If the type of source implements IQueryable, AsQueryable(IEnumerable) returns it directly. Otherwise, it returns an IQueryable that executes queries by calling the equivalent query operator methods in Enumerable instead of those in Queryable.

Is the repository pattern dead?

That is, it’s dead if you are using Entity Framework Core. If you’re still using straight ADO.NET, or even just dapper, then the repository pattern still probably makes sense for you.

Is DbContext a repository?

And, to answer your question title: Yes. DbContext is already acting as a repository.

Should I use IQueryable or IEnumerable?

IEnumerable: IEnumerable is best suitable for working with in-memory collection (or local queries). IEnumerable doesn’t move between items, it is forward only collection. IQueryable: IQueryable best suits for remote data source, like a database or web service (or remote queries).

Is IQueryable faster than IEnumerable?

IQueryable : IQueryable fetches the Record based on filter wise. IQueryable is faster than IEnumerable. In addition to Munesh Sharma’s answer:IEnumerable loads data in-memory and then apply filters to it one by one but IQueryable apply filters all at once and return the result.

What is difference between IQueryable and IEnumerable in C#?

Both IEnumerable and IQueryable are forward collection. Querying data from a database, IEnumerable execute a select query on the server side, load data in-memory on a client-side and then filter data. Querying data from a database, IQueryable execute the select query on the server side with all filters.

What is the use of AsParallel in C#?

AsParallel(Partitioner) Enables parallelization of a query, as sourced by a custom partitioner that is responsible for splitting the input sequence into partitions.

What happens when you return IQueryable from your repositories?

Returning IQueryable from your repository automatically forces the domain logic to make several assumptions. As I sort of mentioned before, the first assumption is that the domain is responsible for writing query logic.

How to implement the repository pattern with direct IQueryable support?

Implementing the IQueryable (or in this case, the IOrderedQueryable ) is actually not the big part of the task: So, the key points here: Basically, this is an implementation for the interface. The implementation takes an instance of the DbContext, like every other repository would do. This instance is used for the usual C.U.D. operations.

How to implement the repository pattern in Java?

You have to implement an interface, which has two methods: one for creating the query and for executing it (actually, there are four methods, the generic and the non-generic version for both, but the non-generic simply uses reflection magic to call the generic):

Where does the magic happen in the repository pattern?

The properties are simply added to the class, the GetEnumerator () simply executes the query and calls into its GetEnumerator (), the Expression is initialized to the current instance. The magic happens inside the query provider: that’s the component that’s actually responsible for executing the query.