linq where clause problem on multiple join tables

var studentDetails = from aspUser in db.aspnet_Users
join aspMembership in db.aspnet_Memberships on
    aspUser.UserId equals aspMembership.UserId
join expUser in db.explore_users on
           aspUser.UserId equals expUser.aspnetUserId
               where expUser.Id.Equals(studID)
               select new { expUser.DOB,
                            aspMembership.Email,
                            aspUser.UserName,
                            aspUser.LoweredUserName,
                            expUser.Id };

gv1开发者_如何学编程.DataSource = studentDetails;
gv1.DataBind();

I have no idea why this did not work. When i remove where clause everything is running. I have try to put where expUser.Id == studID is also did not work

if anyone can help me pls

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Shouldn't that be where expUser.aspnetUserId.Equals(studID)?

If ID is the correct column then (as already commented) of what type are expUser.ID and the variable studID? Are they of the same type? If so then does the studID value exist in db.explore_users?