Explain the difference between IEnumerable and IQueryable in .NET. When would you use one over the other?

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Accepted Answer

IEnumerable is in-memory collection while IQueryable is for querying data from database. Use IEnumerable for LINQ to Objects and IQueryable for LINQ to SQL.

IEnumerable is used for querying data from in-memory collections like List, Array, etc.
IQueryable is used for querying data from a database using LINQ providers like Entity Framework.
IEnumerable executes the query on the client-side, while IQueryable executes the query on the database server.
Use IEnumerable when working with LINQ to Objects and in-memory collections, and use IQueryable when working with LINQ to SQL or Entity Framework.
Example: var customers = dbContext.Customers.AsQueryable(); // IQueryable

Explain the difference between IEnumerable and IQueryable in .NET. When would you use one over the other?

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