Using inline sql with entity frame work and c#

We are having som performance issue with EF and I want to try rewrite a query to inline sql. However I am having some difficulties, it is probably just a noob issue.

Lets say I have 3 classes: License, GroupLicense and Product

    public class License
{
//stuff
Product MyProduct{get;set}
}

public class GroupLicense:License
{
// more stuff
}

public class Product
{
//product info stuff
}

Now I need to fetch some Grouplicenses depending on some requirements. However doing it with the datacontext and linq takes 2 minutes. Something similar to this

var institutionLicenses = db.GroupLicenses
            .Include(lic => lic.Product).Where(x => productIds.Contains(x.Product.Id) && x.LicenseStatus == StatusEnum.Active).ToList();

I want to do the same query using inline sql similar to this: I join the tables so all the primitive fields are okay.

 var gl = db.Database.SqlQuery<GroupLicense>("select * from GroupLicense as g left join Licenses on g.Id =Licenses.Id").ToList();

(It is just example code - I know it is not working :))

However when executing, The base product property on License is null, all the primitive fields are there.

What do I need to change in my sql statement to make it work?