NotSupportedException: The method 'Join' is not supported.

biconix

I create a little c# expression with a join statement on a CRM database. I received the error:
NotSupportedException: The method 'Join' is not supported.

is this a CRM related error? I get the same error whether it is an expression, statement or program

nescafe

Probably WCF OData related.

Try using navigation properties if they exist or .AsEnumerable() to retrieve data sets separately and do the join locally.

The latter will result in a lot more requests, more data being transferred and potentially lack of results due to late filtering and paging.

Example navigation property:

// http://services.odata.org/V3/Northwind/Northwind.svc
from o in Orders
select new { o.Customer.CompanyName, o.OrderDate }

Request log:

http://services.odata.org/V3/Northwind/Northwind.svc/Orders()?$expand=Customer&$select=Customer/CompanyName,OrderDate

Example .AsEnumerable():

// http://services.odata.org/V3/Northwind/Northwind.svc
from o in Orders.AsEnumerable()
join c in Customers.AsEnumerable() on o.CustomerID equals c.CustomerID
select new { o.OrderDate, c.CompanyName }

Request log:

http://services.odata.org/V3/Northwind/Northwind.svc/Customers
http://services.odata.org/V3/Northwind/Northwind.svc/Orders

(due to max. 200 items fetched per request and no paging, the result is incomplete)