c# - LINQ to Entity Query - duplicates in a group -

folks,

i need linq entity query.

i have following table holds list of shifts , user assigned each of shifts below:

shiftid | startdatetime | enddatetime | assigneduserid |

what trying pull out shiftid shifts have been assigned user on same date , time. should not happen person cannot in 2 places @ once...(this 1 has been sorted...now)

we have instances in our database same user has been assigned work on 2 different shifts on same date , time.

e.g.

56 | 06/08/2015 13:00:00 | 06/08/2015 17:00:00 | 22

64 | 06/08/2015 13:00:00 | 06/08/2015 17:00:00 | 22

hope can this, start pull out users have been assigned shifts on same start date ?

 public ilist<shiftdate> getduplicateshifts()     {         return _uow.shiftdate.get()             .tolist();     } 

update

ok, im getting there, able pull out groups of users user on 2 dates on same day, code below works:

public ilist<shiftdate> getduplicateshiftsbyorg(int orgid)     {         ilist<shiftdate> alldates = _uow.shiftdates             .get(s => s.shift.organisationid == orgid)             .where(s=>s.assigneduserid != null)             .tolist();          var duplicatedates = new list<shiftdate> { };          var groups = alldates.groupby(s=>s.assigneduserid.value).where(g => g.skip(1).any());          foreach (var group in groups)         {             var group2 = group.groupby(sd => sd.shiftstartdate.date).where(a => a.count() > 1).tolist();              if (group2.count() > 1)             {               ///// ref 1 : pulls out shiftdates in group one, want shiftdates in group2.                foreach (shiftdate shiftdate in group)                 {                         duplicatedates.add(shiftdate);                 }   /////////////////////////////////////////////////////////              }          }          return duplicatedates.tolist();     } 

as see @ ref 1 above in code want pull out shiftdates in group2. when try following error:

unable cast object of type 'grouping[system.datetime,mysolution.poco.shiftdate]' type 'mysolution.poco.shiftdate'. 

update

the error above appearing because trying return shiftdate group of shift dates, had add loop cycle through groups first. see solution below

try this:

var dt=datetime.now().tostring("mm/dd/yyyy");  var result = t in table1 c.startdate=dt select new {c.assigneduserid};