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Prevent Entity Framework query from being evaluated locally

I have this query that is being partially evaluated locally and I am wondering how to prevent it.
It seems to be the conditional select that is causing the problem.
var fetchQuery = (
from udg in _entities.UberDirectGroups.AsNoTracking()
join uber in _entities.Ubers.AsNoTracking()
on udg.Id equals uber.Id
let memberCount = (
from t in _entities.UberDirects.AsNoTracking()
join u in _entities.Ubers.AsNoTracking()
on t.UberToId equals u.Id
where t.UberFromId == udg.Id && !u.Deleted
select u.UberTypeId == (byte)UberType.User ? 1 :
u.UberTypeId == (byte)UberType.Department ? u.Department.Users.Where(user => user.Deleted == false).Count() :
u.UberTypeId == (byte)UberType.Office ? u.tblOffice.tblDepartment.SelectMany(d => d.Users).Where(user => user.Deleted == false).Count() :
u.UberTypeId == (byte)UberType.ProjectGroup ? u.Group.GroupMembers.Select(pm => pm.User).Where(user => user.Deleted == false).Count() :
u.UberTypeId == (byte)UberType.Role ? _entities.Roles.Where(r => r.RoleDataId == u.tblRoleData.Id).Select(r => r.tblUser).Where(user => user.Deleted == false).Count() : 0
).Sum()
where
udg != null &&
uber != null &&
uber.InstanceId == instanceId &&
(!isSearch || udg.Name.Contains(searchText))
select new TargetGroupProjection
{
id = udg.Id,
name = udg.Name,
created = uber.Date,
toCount = memberCount
}
);

Slow LINQ Query on Join

I'm using EF 6 with .NET Core. I have written the following query to select some data into a custom object. At the moment the main query returns over 25000 records. Then the filters are applied. This query is running very slow. I'm just trying to find out if I'm doing any mistakes here. Why it could be so slow and is the filtering happening on the memory rather than on the database side?
public IQueryable<TicketViewModel> GetTickets(int companyId, string locale, TicketFilterViewModel filters, Guid customerRef, int? take, int currentUser)
{
IQueryable<TicketViewModel> tickets = (from to in _context.Ticket
join co in _context.Company on to.CompanyId equals co.CompanyId
join con in _context.Contact on to.ContactId equals con.ContactId
join site in _context.Site on to.SiteId equals site.SiteId
join country in _context.Country on site.CountryId equals country.CountryId
join cus in _context.Customer on con.CustomerId equals cus.CustomerId
join tic_type in _context.TicketType on to.TicketTypeId equals tic_type.TicketTypeId
join ts in _context.TicketStatus on to.TicketStatusId equals ts.TicketStatusId
join sb in _context.ServiceBoard on to.ServiceBoardId equals sb.ServiceBoardId into ob1
from a in ob1.DefaultIfEmpty()
join u in _context.User on to.TechnitianId equals u.Id into ob2
from b in ob2.DefaultIfEmpty()
join pr in _context.Priority on to.PriorityId equals pr.PriorityId into ob3
from c in ob3.DefaultIfEmpty()
where to.CompanyId == companyId && (customerRef == Guid.Empty || cus.RefNo == customerRef)
&& to.MergedIntoTicketId == null
select new TicketViewModel
{
CreatedOn = Helpers.Custom.UtcToStandardTime(locale, to.AddedOnUtc).ToString("dd/MM/yyyy hh:mm tt"),
CustomerName = cus.CustomerName,
TicketNumber = to.TicketNumber,
TicketTitle = to.TicketTitle,
RefNo = to.RefNo,
CompanyName = co.CompanyName,
ContactName = string.Concat(con.FirstName, " ", con.LastName),
SiteAddress = String.Concat(site.AddressLine1, ", ", site.AddressLine2, ", ", site.Suburb, ", ", site.State, ", ", site.PostCode, ", ", country.Name),
ServiceBoardName = a.BoardName,
TechnicianName = string.Concat(b.FirstName, " ", b.LastName),
PriorityName = c.PriorityName,
TicketStatus = ts.StatusName, //d.StatusName,
ServiceBoardId = to.ServiceBoardId,
TicketStatusId = to.TicketStatusId,
CustomerId = cus.CustomerId,
PriorityId = to.PriorityId,
ContractId = site.ContractId,
TechnitianId = to.TechnitianId,
TicketId = to.TicketId,
StatusCategoryId = ts.CategoryId,//,//d.CategoryId,
DueOnUtc = to.DueOnUtc,
DefaultStatusId = ts.DefaultId,//d.DefaultId,
ClosedOnUtc = to.ClosedOnUtc,
ResolvedOnUtc = to.ResolvedOnUtc,
InitialResponseMade = to.InitialResponseMade,
TicketTypeId = to.TicketTypeId,
TicketTypeName = tic_type.TicketTypeName
}).OrderByDescending(o => o.TicketNumber);
bool isFiltersHit = false;
if (filters != null)
{
if (tickets != null && tickets.Count() > 0 && filters.serviceboard_selectedItems != null && filters.serviceboard_selectedItems.Count > 0)
{
isFiltersHit = true;
tickets = tickets.Where(x => x.ServiceBoardId != null && filters.serviceboard_selectedItems.Select(o => o.serviceBoardId).Contains(x.ServiceBoardId.Value));
}
if (tickets != null && tickets.Count() > 0 && filters.status_selectedItems != null && filters.status_selectedItems.Count > 0)
{
isFiltersHit = true;
tickets = tickets.Where(x => x.TicketStatusId != null && filters.status_selectedItems.Select(o => o.ticketStatusId).Contains(x.TicketStatusId.Value));
}
if (tickets != null && tickets.Count() > 0 && filters.type_selectedItems != null && filters.type_selectedItems.Count > 0)
{
isFiltersHit = true;
tickets = tickets.Where(x => filters.type_selectedItems.Select(o => o.ticketTypeId).Contains(x.TicketTypeId));
}
if (tickets != null && tickets.Count() > 0 && filters.technician_selectedItems != null && filters.technician_selectedItems.Count > 0)
{
isFiltersHit = true;
tickets = tickets.Where(x => x.TechnitianId != null && filters.technician_selectedItems.Select(o => o.id).Contains(x.TechnitianId.Value));
}
if (tickets != null && tickets.Count() > 0 && filters.customer_selectedItems != null && filters.customer_selectedItems.Count > 0)
{
isFiltersHit = true;
tickets = tickets.Where(x => x.CustomerId != 0 && filters.customer_selectedItems.Select(o => o.customerId).Contains(x.CustomerId));
}
if (tickets != null && tickets.Count() > 0 && filters.priority_selectedItems != null && filters.priority_selectedItems.Count > 0)
{
isFiltersHit = true;
tickets = tickets.Where(x => x.PriorityId != null && filters.priority_selectedItems.Select(o => o.priorityId).Contains(x.PriorityId.Value));
}
if (tickets != null && tickets.Count() > 0 && filters.contract_selectedItems != null && filters.contract_selectedItems.Count > 0)
{
isFiltersHit = true;
tickets = tickets.Where(x => x.ContractId != null && filters.contract_selectedItems.Select(o => o.contractId).Contains(x.ContractId.Value));
}
if (tickets != null && tickets.Count() > 0 && filters.source_selectedItems != null && filters.source_selectedItems.Count > 0)
{
isFiltersHit = true;
tickets = tickets.Where(x => x.SourceId != 0 && filters.source_selectedItems.Select(o => o.item_id).Contains(x.SourceId));
}
}
if (take.HasValue)
return tickets.Take(take.Value);
return tickets;
}

If you compose the query based on your conditions from the filters, you will see a big improvement. Meaning, create a base query ( base and minimum conditions ) and then add the conditions one by one, depending on what your filters are. Execute the query after all filters are checked.
P.S: you don't really need to call tickets.Count() on every filter. Do it once, in the beginning.

Linq to SQL : How to do WHERE [Column] = Element in LIST ?

First of all, i've seen many posts like mine but I didn't find the answer.
So, I try to find the equivalent of the "IN" clause for an linq to SQL request and i find something :
IList<int> listClientId = GetAllClientIdByRegionLPS(statutRegion);
if (!statutRegion.Equals(""))
q = q.Where(p => listClientId.Contains((int)p.ClientId));
But that makes me an error :
"'boolean contains(int32)' has no supported translation to sql"
What i want to do :
SELECT ...
FROM ...
WHERE [CONDITIONS]
AND (id == 1 OR id ==2 OR id==3 OR ...)
Let's see my code :
public IList<Appel> GetAllCourants(string Filter, int? StatutFacturation, int? statutDemande, int? statutPro, string statutRegion)
{
var q = from p in DbContext.Appels
where (p.Client.Nom.Contains(Filter) || p.AppelId.ToString().Contains(Filter) || (p.Materiel.Modele1.Nom + " #" + p.Materiel.NumeroSerie).Contains(Filter) || p.ContactClient.Nom.Contains(Filter) || p.ContactClient.Prenom.Contains(Filter) || p.Dossier.Contains(Filter) || p.Client.CodePostal.Contains(Filter) || p.Client.Ville.Contains(Filter) || p.NumDevis.Contains(Filter))
select p;
q = q.Where(p => p.StatutAppelId == 1 || p.StatutAppelId == 9 || p.StatutAppelId == 10 || p.StatutAppelId == 13 || p.StatutAppelId == 14 || p.StatutAppelId == 15 || p.StatutAppelId == 16 || p.StatutAppelId == 17 || p.StatutAppelId == 18);
if (StatutFacturation.HasValue)
q = q.Where(p => p.Facturable == StatutFacturation.Value);
if (statutDemande.HasValue)
q = q.Where(p => p.StatutDemandePiece == statutDemande.Value);
if (statutPro.HasValue)
q = q.Where(p => p.Depot == statutPro.Value);
//This makes me troubles
IList<int> listClientId = GetAllClientIdByRegionLPS(statutRegion);
if (!statutRegion.Equals(""))
q = q.Where(p => listClientId.Contains((int)p.ClientId)); /*Try to do p.ClientId = listClientId*/
var ret = q.Select(p => Deserialize<Generated.Appel>(p)).ToList();
return ret;
}
How can I fixe it ?
Thanks a lot in advance !

Try changing
IList<int> listClientId = GetAllClientIdByRegionLPS(statutRegion);
to
List<int> listClientId = GetAllClientIdByRegionLPS(statutRegion);

Linq2Sql strange behaviour

in my DB, I have e.g. 13 orders.
The code below returns all of them, if the OrderID = 0 and CustomerName = "lorem".
If I comment the line (OrderID == 0) ?.... it works fine. What's wrong ?
var result = (from x in db.Order
where
(OrderID == 0) ? x.OrderID > 0 : x.OrderID == OrderID
&&
(string.IsNullOrEmpty(CustomerName)) ?
!string.IsNullOrEmpty(CustomerName)
:
x.User.Name.Contains(CustomerName)
select x)
.ToList();

I think you can not define conditional condition inside LINQ query in this way, what you can do is, for example:
var result = (from x in db.Order where
((OrderID == 0 && x.OrderID > 0) ||
(OrderID != 0 && x.OrderID == OrderID))
&&
(string.IsNullOrEmpty(CustomerName)) ?
!string.IsNullOrEmpty(CustomerName)
:
x.User.Name.Contains(CustomerName)....

Problem with LINQ query

The following works fine:
(from e in db.EnquiryAreas
from w in db.WorkTypes
where
w.HumanId != null &&
w.SeoPriority > 0 &&
e.HumanId != null &&
e.SeoPriority > 0 &&
db.Enquiries.Where(f =>
f.WhereId == e.Id &&
f.WhatId == w.Id &&
f.EnquiryPublished != null &&
f.StatusId != EnquiryMethods.STATUS_INACTIVE &&
f.StatusId != EnquiryMethods.STATUS_REMOVED &&
f.StatusId != EnquiryMethods.STATUS_REJECTED &&
f.StatusId != EnquiryMethods.STATUS_ATTEND
).Any()
select
new
{
EnquiryArea = e,
WorkType = w
});
But:
(from e in db.EnquiryAreas
from w in db.WorkTypes
where
w.HumanId != null &&
w.SeoPriority > 0 &&
e.HumanId != null &&
e.SeoPriority > 0 &&
EnquiryMethods.BlockOnSite(db.Enquiries.Where(f => f.WhereId == e.Id && f.WhatId == w.Id)).Any()
select
new
{
EnquiryArea = e,
WorkType = w
});
+
public static IQueryable<Enquiry> BlockOnSite(IQueryable<Enquiry> linq)
{
return linq.Where(e =>
e.EnquiryPublished != null &&
e.StatusId != STATUS_INACTIVE &&
e.StatusId != STATUS_REMOVED &&
e.StatusId != STATUS_REJECTED &&
e.StatusId != STATUS_ATTEND
);
}
I get the following error:
base {System.SystemException}: {"Method 'System.Linq.IQueryable1[X.Enquiry]
BlockOnSite(System.Linq.IQueryable1[X.Enquiry])' has no supported translation to SQL."}

Linq to Sql only translates certain method calls to SQL, and yours (BlockOnSite) is not one of them. Hence the error. The fact that your method takes an IQueryable<T> and returns an IQueryable<T> doesn't make it special.

Ok I solved it using:
IQueryable<Enquiry> visibleOnSite = EnquiryMethods.VisibleOnSite(db.Enquiries);
var combinations = (from e in db.EnquiryAreas
from w in db.WorkTypes
where
w.HumanId != null &&
w.SeoPriority > 0 &&
e.HumanId != null &&
e.SeoPriority > 0 &&
visibleOnSite.Where(f => f.WhereId == e.Id && f.WhatId == w.Id).Any()
select
new
{
EnquiryArea = e,
WorkType = w
});