MongoDB LinQ "Select" method will really retrieve only a subset of fields?
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Searching across the internet how to retrieve a subset of fields in MongoDB, using C# official driver (but using LinQ as the base architecture) I found how to do this in MongoDB shell.

    // selecting only "field" of a collection
    db.collection.find( { field : 'value' }, { field: 1 } ); 

Then, I found at C# LinQ Tutorial the `Select` method, which is equivalent to this:

    collection.AsQueryable<T>().Select(x => new { x.field });

However, the tutorial says the method "*is used to project a new result type from the matching documents*".

How to ensure this method will retrieve only the subset of fields and not the entire result and then select only the subset into a new object?

**Will the driver build the query command before retrieve the results?**