LINQ to sharepoint . join list help - linq

Question

I am currently using SharePoint 2010,and in my business layer I am using LINQ to SharePoint. I generated all my Entity classes using SPMetal.
We are creating a Library system, my system has 2 Lists . The first one is Contribution and the second one is Contributor. Each Contributor contains a reference to the Contribution List (a PrimaryISBN reference). The Contribution List contains list of books and PrimaryISBN is not unique in this list.
Contribution
ID PrimaryISBN TITLE
1 PRIM1 HardcoverLOTR
2 PRIM1 AudioBookLOTR
3 PRIM2 HardcoverHP
Contributor
ID Name PrimaryISBNLookup
1 ABC PRIM1
2 DEF PRIM2
I am currently trying to fetch All the Books Contributed by a Particular user based on the Name.
My query is something like this
var result = from _contributor in data.contributor
where _contributor.Name= "ABC"
select new Book
{
Title = contributor.PrimaryISBNLookup.Title
}
The problem that I am currently facing is in retrieving records that have same ISBN but different title (Each format will have a title i.e. a Audio book will have a title and a Hardcover of the same book will have a different one).
This query returns me only 1 records even thought I have 2 records in my system i.e. the record with ID (in Contribution) that I am forced to insert during the insertion of record into Contributor List.
Your help is highly appreciated.

Answer 1

From what I understand, you try to implement a simple join, like this:
var results = from _contributor in data.contributor
join _contribution in data.contribution
on _contributor.PrimaryISBNLookup equals _contribution.PrimaryISBN
where _contributor.Name == "ABC"
select new Book
{
Title = _contribution.Title
}

Answer 2

If you want to use DataTable in SPList, try this:
SPList cList = spWeb.Lists.TryGetList("Customer");
SPList oList = spWeb.Lists.TryGetList("Order");
DataTable cTable= cList.Items.GetDataTable();
DataTable oTable= oList.Items.GetDataTable();
var coList = from tbl1 in cTable.AsEnumerable()
join tbl2 in oTable.AsEnumerable() on tbl1["Title"] equals tbl2["CustomerName"]
select new
{
ItemName = tbl2["Title"],
CustomerName = tbl1["Title"],
Mobile = tbl1["MobileNo"]
};