-
Type:
Bug
-
Resolution: Works as Designed
-
Priority:
Major - P3
-
None
-
Affects Version/s: 2.6.1
-
Component/s: Linq, Read Operations
-
Labels:None
-
Environment:c# driver 2.6.1,
server version 3.4.10
windows 7 sp1 64 bit
I have a class:
class DynamicForm { public long? FolderId { get; set; } public long PatientSystemId { get; set; } public DateTime ModifiedDate { get; set; } }
I have a function that gets the PatientSystemId as parameter GetDynamicFormsAsync(long patientSystemId)
I run the following query:
var query = db.GetCollection<DynamicForm>("dforms").AsQueryable() .Where(a => a.PatientSystemId == patientSystemId && a.FolderId == null) .MaxAsync(a => a.ModifiedDate); var qResult = await query;
When there are documents in the database that meet the filter criteria I do get the Max date as desired.
However, if there is no document meeting the query criteria then I get a run-time exception:
System.InvalidOperationException HResult=0x80131509 Message=The source sequence is empty. Source=MongoDB.Driver StackTrace: at MongoDB.Driver.AsyncCursorHelper.<SingleAsync>d__3`1.MoveNext() at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult() at ..... my code
When patientSystemId parameter equals 51, the following query is generated:
{
"aggregate" : "dforms",
"pipeline" : [
{ "$match" : { "patientSystemId" : NumberLong(51), "folderId" : null } },
{ "$group" : { "id" : 1, "_result" : { "$max" : "$modifiedDate" } } }
],
"cursor" : { }
}
When running this query in mongo shell, no exception occurs.
Can you please address this bug / issue.
Just say that you have read it please.
Thanks,
Itzhak