Merging Multiple IQueryables together - Silverlight - silverlight

Question

Peeps,
Im a born again virgin to Silverlight so please bear with me. I have two seperate DomainServices, pointing to two different SQL Database Servers. Within these Domain Services I have setup some IQueryables in each Domain Service.
I need to merge two IQueryables together from seperate DomainServices. Im sure this has got to be do-able.
Below are the two domain services.
I want to merge GetCustomCallLogs (from HEATLiveDomainService) together with GetTblCallsLogged (from HeatDomainService). The key in GetCustomCallLogs would be the CallID and the key in GetTblCallsLogged would be the RecID.
If its possible to do i understand i would need to create a new type to take into account any fields from the two joined tables.
Hopefully ive explained my scenario, and im not being dumb.
Thanks in advance
public class HEATLIVEDomainService : LinqToEntitiesDomainService<HeatIT9_LiveEntities>
{
// TODO:
// Consider constraining the results of your query method. If you need additional input you can
// add parameters to this method or create additional query methods with different names.
// To support paging you will need to add ordering to the 'Assignees' query.
public IQueryable<Assignee> GetAssignees()
{
return this.ObjectContext.Assignees;
}
// TODO:
// Consider constraining the results of your query method. If you need additional input you can
// add parameters to this method or create additional query methods with different names.
// To support paging you will need to add ordering to the 'CallLogs' query.
public IQueryable<CallLog> GetCallLogs()
{
// return this.ObjectContext.CallLogs.Where(c => DateTime.Parse(c.ClosedDate).Year == 2012 && c.CallStatus == "Closed" && c.ClosedBy.Length > 0);
return this.ObjectContext.CallLogs.Where(c => c.CallStatus == "Closed" && c.ClosedDate.Substring(0, 4).Equals("2013"));
}
public IQueryable<CallLog> GetCallLogsLastThisYear()
{
return this.ObjectContext.CallLogs.Where(c => c.CallStatus == "Closed" && (c.ClosedDate.Substring(0, 4).Equals("2012") || c.ClosedDate.Substring(0, 4).Equals("2013")));
}
public IQueryable<CustomCallLog> GetCustomCallLogs(string year)
{
var result = from i in this.ObjectContext.CallLogs
join p in this.ObjectContext.Assignees on i.ClosedBy equals p.LoginID
where i.CallStatus == "Closed" && i.ClosedDate.Substring(0, 4) == year
select new CustomCallLog
{
Score =
CallLog = i.CallID,
Name = p.Assignee1,
Yr = year,
Mth = i.ClosedDate.Substring(5, 2),
GroupName = p.GroupName
};
return result;
}
public IQueryable<CustomClosedJobs> GetCustomClosedJobs()
{
var result = from i in this.ObjectContext.CallLogs
where i.CallStatus == "Closed" && i.ClosedDate.Substring(0, 4) =="2012"
group i by i.ClosedDate.Substring(5,2) into y
select new CustomClosedJobs
{
Type = "heat",
ClosedCalls = y.Count(),
Mth =y.Key
};
return result;
}
// TODO:
// Consider constraining the results of your query method. If you need additional input you can
// add parameters to this method or create additional query methods with different names.
// To support paging you will need to add ordering to the 'Subsets' query.
public IQueryable<Subset> GetSubsets()
{
return this.ObjectContext.Subsets;
}
}
public class HEATDomainService : LinqToEntitiesDomainService<FEEDBACKPRDEntities1>
{
// TODO:
// Consider constraining the results of your query method. If you need additional input you can
// add parameters to this method or create additional query methods with different names.
// To support paging you will need to add ordering to the 'qryStoringLogs' query.
public IQueryable<qryStoringLog> GetQryStoringLogs()
{
return this.ObjectContext.qryStoringLogs.OrderBy(e => e.monthno);
}
public IQueryable<tblStoringLog> GetTop100Logs()
{
return this.ObjectContext.tblStoringLogs.OrderByDescending(e => e.responsetime).Take(100);
}
public IQueryable<tblStoringLog> GetLogCount(DateTime s, DateTime e)
{
return this.ObjectContext.tblStoringLogs.Where(x => x.responsetime >= s && x.responsetime <= e);
}
public IQueryable<qryStoringLog> GetLogs(int year, int mth)
{
return this.ObjectContext.qryStoringLogs.Where(e => e.Month.Equals(mth) && e.yr.Equals(year));
}
public IQueryable<qryStoringLog> GetLogsForYear(int year)
{
return this.ObjectContext.qryStoringLogs.Where(e => e.yr.Equals(year)).OrderBy(e => e.monthno);
}
public DateTime GetFirstDate()
{
return (DateTime)this.ObjectContext.tblStoringLogs.OrderBy(e => e.responsetime).First().responsetime;
}
public DateTime GetLastDate()
{
return (DateTime)this.ObjectContext.tblStoringLogs.OrderByDescending(e => e.responsetime).First().responsetime;
}
public IQueryable<tblCallLogged> GetTblCallLoggeds()
{
return this.ObjectContext.tblCallLoggeds;
}
public IQueryable<tblStoringLog> GetTblStoringLogs()
{
return this.ObjectContext.tblStoringLogs;
}
[Query(IsComposable = false)]
public IQueryable<qryStoringLog> GetTblStoringLogsStatus(int statusid)
{
return this.ObjectContext.qryStoringLogs.Where(e => e.statusid == statusid);
}
public IQueryable<stResponsesLife_Result> LifeTimeResponses()
{
return this.ObjectContext.stResponsesLife().AsQueryable();
}
public IEnumerable<CustomLifetime> GetCustomLifeTime()
{
var result = from i in this.ObjectContext.stResponsesLife().ToList()
select new CustomLifetime
{
Dates = i.Dates,
Vals = (int)i.Vals
};
return result;
}
public int GetAllResponses()
{
return this.ObjectContext.qryStoringLogs.Count();
}
}
Caveats:
Cannot have linked servers, so doing it at the source (SQL Server) is out of the question.
Cannot create a SP and use OpenQuery (well i could but i want to learn to do it correctly), as im sure this isnt the correct way of doing it.

Answer 1

You may need a third type to wrap the two different types returned from each service, but this depends upon how you want to use it.
An ItemsControl wont care about what types are in the collection (Listbox, combobox etc), but GridView type controls might be picky.
Using linq, both lists can simply be merged. Something like the following should do the trick:
collection1.Select(o => (object)o).Concat(collection2.Select(o => (object)o));
The Select and Cast is so that an appropriate generic collection is created by the query.
This can be adjusted to incorporate conversion to your wrapper type too. ie Instead of casting to Object, just return a new instance of your wrapper class instead.
You can even use a Union if appropriate.
Putting it all together:
collection1.Select(o => new MyWrapperType(o))
.Union(collection2.Select(o => new MyWrapperType(o)));