Question

So, I’m trying to return a collection of People whose ID is contained within a locally created collection of ids ( IQueryable)

When I specify “locally created collection”, I mean that the Ids collection hasnt come from a LinqToSql query and has been programatically created (based upon user input).
My query looks like this:

var qry = from p in DBContext.People
                  where Ids.Contains(p.ID)
                  select p.ID;

This causes the following exception…

“queries with local collections are not supported”

How can I find all the People with an id that is contained within my locally created Ids collection?

Is it possible using LinqToSql?

Answer 1

If Ids is a List, array or similar, L2S will translate into a contains.

If Ids is a IQueryable, just turn it into a list before using it in the query. E.g.:

List<int> listOfIDs = IDs.ToList();  
var query =  
from st in dc.SomeTable  
where listOfIDs.Contains(st.ID)
select .....