Expose IQueryable Over WCF Service

linq wcf iqueryable deferred-execution custom-linq-providers
Trust picture Trust · Nov 27, 2010 · Viewed 9.8k times · Source

I've been learning about IQueryable and lazy loading/deferred execution of queries.

Is it possible to expose this functionality over WCF? I'd like to expose a LINQ-to-SQL service that returns an IQueryable which I can then perform additional queries on at the client, and finally execute using a .ToList(). Is OData format applicable at all in this context?

If possible, what is the term for this technique and what are some good tutorials I can follow? Thank you.

Answer

Ladislav Mrnka picture Ladislav Mrnka · Nov 27, 2010

You should check WCF Data Services which will allow you to define Linq query on the client. WCF Data Services are probably the only solution for your requirement.

IQueryable is still only interface and the functionality depends on the type implementing the interface. You can't directly expose Linq-To-Sql or Linq-To-Entities queries. There are multiple reasons like short living contexts or serialization which will execute the query so the client will get list of all objects instead of the query.

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