Answer
IEnumerable: Executes queries in memory (LINQ to Objects).
IQueryable: Builds expression trees and allows external systems like databases to execute queries.
Quick Answer
Both let you query collections but where the query runs differs. IEnumerable pulls all data to memory first, then filters in C#. IQueryable builds an expression tree and sends it to the data source (like SQL Server) — filtering happens there. For large datasets, always prefer IQueryable.
S
SugharaIQ Editorial Team
Verified Answer
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Source: SugharaIQ