The following LINQ query:

var obj = new[] { 1, 2, 3 };
var queryable = collection.AsQueryable()
    .Where(x => obj.Any(y => x.X== y));

is currently translated generically which results in MQL that is more complicated than necessary for this special case.

In this particular special case where the parameters to `Any` are a constant array and predicate comparing a field to the predicate parameter, the following simpler (and more efficient) MQL can be generated:

{ $match : { X : { $in : [1, 2, 3] } } }