Why AsEnumerable also execute filter on server

Question

I'm using Linq to Entities in my program, and i have the following two simple queries:

var result = dbContext.Customers.Where(c => c.Name == "Mostafa").ToList();
var result2 = dbContext.Customers.Where(c => c.Name == "Mostafa").AsEnumerable().ToList();

when i run the SQL Profiler, i found that the generated SQL Query is the same for both of the queries ! the questions is why in the second query, although i'm using asEnumerable, executes the filtering on the server side ?

Update: The filtering was applied on memory instead of the server when changing the second query to be like this:

var result2 = dbContext.Customers.AsEnumerable().Where(c => c.Name == "Mostafa").ToList();

Thanks to @Willem Van Onsem

Answer 1

AsEnumerable() makes the remainder of the query execute locally. Anything earlier than the AsEnumerable() is still part of the IQueryable execution flow. For example, think about this (imagining an Age property):

var result = dbContext.Customers
    .Where(c => c.Name == "Mostafa")
    .Where(c => c.Age == 18)
    .ToList();

That would result in SQL which filtered by name and age. Compare that with this:

var result = dbContext.Customers
    .Where(c => c.Name == "Mostafa")
    .AsEnumerable()
    .Where(c => c.Age == 18)
    .ToList();

That would filter by name in the SQL, but it would filter by age locally (in memory).