I have a method:
public static void GetObjects()
{
using(MyContext context = new MyContext())
{
var objects = context.Bars.Where(b => b.Prop1
As I discovered in my own question, .Where(o => whereFunc(o))
is not the same as .Where(whereFunc)
in the Entity Framework.
The first one, .Where(Expression
works like any other linq call, simply appending the expression to the expression tree.
In the second case, .Where(Func
, it will compile and evaluate the linq call (which so far is just context.Bars
) before applying the whereFunc
predicate.
So, to answer your question, the second one is much slower because it is pulling the entire Bars
table into memory before doing anything with it. Using .Where(o => whereFunc(o))
instead should fix that
(or, as Mark suggests, change the type of whereFunc to Expression
, which Func
is implicitly convertible to)