var transactions = from t in context.Transactions
group t.Create_Date_Time by t.Participation_Id
into t1
select new { ParticipationId = t1.Key, CreateDateTime = t1.Max() };
var cases = from c in context.Cases
group c.Create_Date_Time by c.Participation_Id
into c1
select new { ParticipationId = c1.Key, CreateDateTime = c1.Max() };
var interactions = (from i in context.Interactions
join pp in context.Party_Participation on i.Party_Id equals pp.Party_Id
group i.Last_Update_Date_Time.HasValue ? i.Last_Update_Date_Time : i.Create_Date_Time by
pp.Participation_Id
into i1
select new {ParticipationId = i1.Key, CreateDateTime = i1.Max()}).AsQueryable();
Considering the above code, following will work
transactions.Union(cases);
However following will not work
transactions.Union(interactions);
Because transactions and cases both are returning Linq.IQueryable
but the last one is Linq.ParallelQuery
due to it join with an another table.
I need this functionality basically to make Union. interactions.Union(transactions)
or transactions.Union(interactions)
one with other开发者_如何学JAVA.
The anonymous type of transactions
and cases
is the same. The anonymous type of interactions
is different!
So the solution is to select
in a way that makes the anonymous types the same. So either create your own type or convert the select product's properties to the same type.
Something like this should produce the same anonymous type for all the selects:
select new { ParticipationId = (int)c1.Key, CreateDateTime = (DateTime)c1.Max() }
My answer to this question may be incorrect however I raised up this question primarly for the following problem. LINQ to Entities Union is throwing an error.
I found a fantastic reply from diceguyd30 and it was solved my problem. Hence I am closing this question in response to my previous question's answer.
interactions.Union(transactions.AsEnumerable());
that should work since the first parameter is IQueryable
and the second is IEnumerable
Queryable.Union<TSource> Method (IQueryable<TSource>, IEnumerable<TSource>)
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