Im trying to compute a boolean field based on a subquery
var dtfs = cntx.Set<Models.DocTypeField>()
.Include(dtf => dtf.Field)
.Where(dtf => dtf.DocTypeId == docTypeId)
.Select(dtf => new
{
DocTypeField = dtf,
HasData = (cntx.Set<Models.DocumentData>()
.Any(dd => dd.DocTypeId == dtf.DocTypeId
&& dd.DataValues.Any(ddv => ddv.FieldId == dtf.FieldId)))
});
There is no navigation property(or traversable path) between DocTypeField and DocumentData. When I run the query above I get the following exception:
Test method
Core.Sebring.DataAccess.Ef.Test.EF_DocTypeDALTest.EF_DocTypeDALTest_GetDocTypeIndexes
threw exception:
System.NotSupportedException:
LINQ to Entities does not recognize the method
'System.Data.Entity.DbSet`1[Core.Sebring.Models.DocumentData]
Set[DocumentData]()' method, and this method cannot be translated
into a store expression.
Is there a linq to entity way of accomplishing the above query? I would rather not add a navigation property(or traversable path) between DocTypeField and DocumentData, if possible.
*UPDATE 1*
As a work around I did
class FieldDocTypeField
{
public int DocTypeFieldId { get; set; }
public int DocTypeId { get; set; }
public int FieldDataType { get; set; }
public int FieldId { get; set; }
public byte[] LastChanged { get; set; }
public bool Required { get; set; }
public string FieldName { get; set; }
public bool HasData { get; set; }
}
var dtfs = cntx.DbContext.Database.SqlQuery<FieldDocTypeField>(#"select dtf.*,f.*,
HasData = (CASE WHEN EXISTS(Select DocumentDataValue.FieldId
from DocumentData
inner join DocumentDataValue on DocumentData.DocumentDataId=DocumentDataValue.DocumentDataId
where DocumentData.DocTypeId = #DocTypeId AND dtf.FieldId = 1) THEN cast(1 as bit) ELSE cast(0 as bit) END)
from DocTypeField dtf
inner join Field f on dtf.FieldId = f.FieldId WHERE dtf.DocTypeId=#DocTypeId", new System.Data.SqlClient.SqlParameter("#DocTypeId", docTypeId));
foreach (var dtf in dtfs)
{
docTypeFields.Add(new Models.DocTypeField
{
DocTypeFieldId = dtf.DocTypeFieldId,
DocTypeId = dtf.DocTypeId,
FieldDataType = dtf.FieldDataType,
FieldId = dtf.FieldId,
LastChanged = dtf.LastChanged,
Required = dtf.Required,
FieldName = dtf.FieldName,
HasData = dtf.HasData
});
}
Its not so nice but it works and accomplishes the same things. I could not find a way to do the above using linq to entities without adding a nav property between DocTypeField and DocumentData entities.
You can pull the data in memory first and then do the 2nd select.
var dtfs = cntx.Set<Models.DocTypeField>()
.Include(dtf => dtf.Field)
.Where(dtf => dtf.DocTypeId == docTypeId)
.ToList() // pull the data to memory and then the following select can execute successfully.
.Select(dtf => new
{
DocTypeField = dtf,
HasData = (cntx.Set<Models.DocumentData>()
.Any(dd => dd.DocTypeId == dtf.DocTypeId
&& dd.DataValues.Any(ddv => ddv.FieldId == dtf.FieldId)))
});
Related
I'm sure someone else has asked this but I searched on what I could think of to find the solution.
I've got the following data models to match tables in my SQL db:
public class ProfileDetailModel
{
public string id { get; set; }
public string name { get; set; }
public StyleList[] styleList { get; set; }
public FabricList[] fabricList { get; set; }
}
public class StyleList
{
public string id { get; set; }
public string name { get; set; }
}
public class FabricList
{
public string id { get; set; }
public string fabricName { get; set; }
}
This is the current query code:
var query = (from t in db.tblProfiles
select new ProfileDetailModel()
{
id = t.id,
name = t.name
});
var querylist = await query.ToListAsync();
(prototyped linq queries below for style and fabric)
var styleQuery = (from t in db.tblStyles
select new styleList()
{
id = t.id,
name = t.name
});
var fabricQuery = (from t in db.tblFabrics
select new fabricList()
{
id = t.id,
name = t.name
});
if (queryList.Count > 0)
{
var item = queryList[0];
item.styleList = styleQuery;
item.fabricList = fabricQuery;
}
I'll have one profileDetailModel with multiple items in styleList and in fabricList. EG.
ProfileDetailModel
Data: Pants
styleList: Bell Bottom, Straight Leg, Boot fit
fabricList: jean-blue, jean-black, plaid
All three above models are tables in my db. I could issue 3 separate queries to read the data then assemble after the fact. But is there a way I can do a linq query to include the two arrays in the main query in one shot?
Try this:
var newQuery = (from p in db.tblProfiles
select p)
.AsEnumerable()
.Select(x => new ProfileDetailModel()
{
id = x.id,
name = x.name,
styleList = styleQuery,
fabricList = fabricQuery
});
I have to next 2 entities in my project
public class Product
{
public Product()
{
this.ProductImages = new HashSet<ProductImage>();
this.ProductParams = new HashSet<ProductParam>();
}
public int ID { get; set; }
public int BrandID { get; set; }
public int CodeProductTypeID { get; set; }
public string SeriaNumber { get; set; }
public string ModelNumber { get; set; }
public decimal Price { get; set; }
public bool AvailableInStock { get; set; }
public virtual Brand Brand { get; set; }
public virtual CodeProductType CodeProductType { get; set; }
public virtual ICollection<ProductImage> ProductImages { get; set; }
public virtual ICollection<ProductParam> ProductParams { get; set; }
}
public class ProductParam
{
public int Id { get; set; }
public int ProductId { get; set; }
public int CodeProductParamId { get; set; }
public string Value { get; set; }
public virtual Product Product { get; set; }
public virtual CodeProductParam CodeProductParam { get; set; }
}
and I want to get list of Products which has list of specified parameters
var prodParamCritria = new List<ProductParam>()
{
new ProductParam(){CodeProductParamId =1, Value="Black" },
new ProductParam(){CodeProductParamId =2, Value="Steal"}
};
in sql I can do it by using EXISTS clause twise
SELECT *
FROM Products p
WHERE EXISTS (
SELECT *
FROM ProductParams pp
WHERE pp.ProductId = p.ID
AND (pp.CodeProductParamId = 1 AND pp.[Value] = N'Black')
)
AND EXISTS (
SELECT *
FROM ProductParams pp
WHERE pp.ProductId = p.ID
AND pp.CodeProductParamId = 2
AND pp.[Value] = N'Steal'
)
How can i get same result by EF methods or linq
Try this:
var products= db.Products.Where(p=>p.ProductParams.Any(pp=>pp.CodeProductParamId == 1 && pp.Value == "Black") &&
p.ProductParams.Any(pp=>pp.CodeProductParamId == 2 && pp.Value == "Steal"));
Update
The problem in work with that list of ProductParam to use it as a filter is that EF doesn't know how to translate a PodructParam object to SQL, that's way if you execute a query like this:
var products2 = db.Products.Where(p => prodParamCritria.All(pp => p.ProductParams.Any(e => pp.CodeProductParamId == e.CodeProductParamId && pp.Value == e.Value)));
You will get an NotSupportedException as you comment in the answer of #BostjanKodre.
I have a solution for you but probably you will not like it. To resolve that issue you could call the ToList method before call the Where. This way you will bring all products to memory and you would work with Linq to Object instead Linq to Entities, but this is extremely inefficient because you are filtering in memory and not in DB.
var products3 = db.Products.ToList().Where(p => prodParamCritria.All(pp => p.ProductParams.Any(e => pp.CodeProductParamId == e.CodeProductParamId && pp.Value == e.Value)));
If you want filter by one criteria then this could be more simple and you are going to be able filtering using a list of a particular primitive type. If you, for example, want to filter the products only by CodeProductParamId, then you could do this:
var ids = new List<int> {1, 2};
var products = db.Products.Where(p => ids.All(i=>p.ProductParams.Any(pp=>pp.CodeProductParamId==i))).ToList();
This is because you are working with a primitive type and not with a custom object.
I suppose something like that should work
db.Product.Where(x => x.ProductParams.FirstOrDefault(y => y.CodeProductParamId == 1) != null && x.ProductParams.FirstOrDefault(y => y.CodeProductParamId == 2) != null).ToList();
or better
db.Product.Where(x => x.ProductParams.Any(y => y.CodeProductParamId == 1) && x.ProductParams.Any(y => y.CodeProductParamId == 2)).ToList();
Ok, if you need to make query on parameters in list prodParamCriteria it will look like this:
db.Product.Where(x => prodParamCritria.All(c=> x.ProductParams.Any(p=>p.CodeProductParamId == c.CodeProductParamId && p.Value== c.Value))).ToList();
I forgot that complex types cannot be used in query database, so i propose you to convert your prodParamCriteria to dictionary and use it in query
Dictionary<int, string> dctParams = prodParamCritria.ToDictionary(x => x.CodeProductParamId , y=>y.Value);
db.Product.Where(x => dctParams.All(c => x.ProductParams.Any(p=> p.CodeProductParamId == c.Key && p.Value== c.Value))).ToList();
another variation:
IEnumerable<Int32> lis = prodParamCritria.Select(x => x.CodeProductParamId).ToList();
var q = Products.Select(
x => new {
p = x,
cs = x.ProductParams.Where(y => lis.Contains(y.Id))
}
).Where(y => y.cs.Count() == lis.Count()).
ToList();
with a named class like (or maybe without, but not in linqpad)
public class daoClass {
public Product p {get; set;}
public Int32 cs {get; set;}
}
IEnumerable<Int32> lis = prodParamCritria.Select(x => x.CodeProductParamId).ToList();
var q = Products.Select(
x => new daoClass {
p = x,
cs = x.ProductParams.Where(y => lis.Contains(y.Id))
}
).Where(y => y.cs.Count() == lis.Count()).
SelectMany(y => y.p).
ToList();
I have the following class
public class SolicitacaoConhecimentoTransporte
{
public long ID { get; set; }
public string CodigoOriginal { get; set; }
public DateTime Data { get; set; }
public List<CaixaConhecimentoTransporte> Caixas { get; set; }
}
I would like to know if there is a way of achiveing the same behavior of the code below using Linq (with lambda expression syntax),
List<SolicitacaoConhecimentoTransporte> auxList = new List<SolicitacaoConhecimentoTransporte>();
foreach (SolicitacaoConhecimentoTransporte s in listaSolicitacao)
{
SolicitacaoConhecimentoTransporte existing =
auxList.FirstOrDefault(f => f.CodigoOriginal == s.CodigoOriginal &&
f.Data == s.Data &&
f.ID == s.ID);
if (existing == null)
{
auxList.Add(s);
}
else
{
existing.Caixas.AddRange(s.Caixas);
}
}
return auxList;
In other words, group all entities that have equal properties and flat all lists into one.
Thanks in advance.
Use anonymous object to group by three properties. Then project each group to new SolicitacaoConhecimentoTransporte instance. Use Enumerable.SelectMany to get flattened sequence of CaixaConhecimentoTransporte from each group:
listaSolicitacao.GroupBy(s => new { s.CodigoOriginal, s.Data, s.ID })
.Select(g => new SolicitacaoConhecimentoTransporte {
ID = g.Key.ID,
Data = g.Key.Data,
CodigoOriginal = g.Key.CodigoOriginal,
Caixas = g.SelectMany(s => s.Caixas).ToList()
}).ToList()
I have a query like this :
List<PresentClass.userpresentation> q =
(dbconnect.tblUsers.Where(
i => i.permission == permission)
.Select(arg => new PresentClass.userpresentation {
email = arg.email, pass = arg.password,
name = arg.name+" "+arg.family })).ToList();
After adding an orderby :
List<PresentClass.userpresentation> q =
(dbconnect.tblUsers.Where(
i => i.permission == permission)
.Select(arg => new PresentClass.userpresentation {
email = arg.email, pass = arg.password,
name = arg.name+" "+arg.family })).OrderBy(i=>i.family).ToList();
I got this error :
The member
'Novitiate.AdminPortal.PresentationClass.PresentClass+userpresentation.family'
has no supported translation to SQL.
My class:
public class userpresentation
{
public string username { set; get; }
public string email { set; get; }
public string family { set; get; }
public string name { set; get; }
public string pass{ set; get; }
}
Why?
It looks like it's trying to translate the OrderBy() into a SQL statement on your projection.
Try adding the OrderBy() before Select() if you want the database to do the ordering, or after the ToList() if you want to do the ordering once the collection has been loaded.
var q = (dbconnect.tblUsers.Where(i => i.permission == permission)
.OrderBy(i=>i.family)
.Select(arg => new PresentClass.userpresentation {
email = arg.email,
pass = arg.password,
name = arg.name+" "+arg.family
})).ToList();
I have a query that works fine when using an anonymous type but as soon as I try to un-anonymize it it fails to select all values into the class.
here is the linq i'm using (in combination with Subsonic 3):
var producten = (from p in Premy.All()
join pr in Producten.All() on p.dekking equals pr.ID
where p.kilometragemax >= 10000 &&
p.CCmin < 3000 &&
p.CCmax >= 3000 &&
p.leeftijdmax >= DateTime.Today.Subtract(car.datumEersteToelating).TotalDays / 365
group p by new { pr.ID, pr.Naam, pr.ShortDesc, pr.LongDesc } into d
select new
{
ID = d.Key.ID,
Dekking = d.Key.Naam,
ShortDesc = d.Key.ShortDesc,
LongDesc = d.Key.LongDesc,
PrijsAlgemeen = d.Min(x => x.premie),
PrijsAlgemeenMaand = d.Min(x => x.premie),
PrijsMerkdealerMaand = d.Min(x => x.premie),
PrijsMerkdealer = d.Min(x => x.premie)
}).ToList();
When I change it to:
List<QuotePremies> producten = (from p in Premy.All()
join pr in Producten.All() on p.dekking equals pr.ID
where p.kilometragemax >= 10000 &&
p.CCmin < 3000 &&
p.CCmax >= 3000 &&
p.leeftijdmax >= DateTime.Today.Subtract(car.datumEersteToelating).TotalDays / 365
group p by new { pr.ID, pr.Naam, pr.ShortDesc, pr.LongDesc } into d
select new QuotePremies
{
ID = d.Key.ID,
Dekking = d.Key.Naam,
ShortDesc = d.Key.ShortDesc,
LongDesc = d.Key.LongDesc,
PrijsAlgemeen = d.Min(x => x.premie),
PrijsAlgemeenMaand = d.Min(x => x.premie),
PrijsMerkdealerMaand = d.Min(x => x.premie),
PrijsMerkdealer = d.Min(x => x.premie)
}).ToList();
in combination with this class:
public class QuotePremies
{
public byte ID { get; set; }
public string Dekking { get; set; }
public string ShortDesc { get; set; }
public string LongDesc { get; set; }
public decimal PrijsAlgemeen { get; set; }
public decimal PrijsAlgemeenMaand { get; set; }
public decimal PrijsMerkdealer { get; set; }
public decimal PrijsMerkdealerMaand { get; set; }
}
it doesn't give me an error but all values in the class are 0 except for QuotePremies.ID, QuotePremies.ShortDesc and QuotePremies.LongDesc. No clue why that happens.
See if using conversion helps
PrijsAlgemeen = Convert.ToDecimal(d.Min(x => x.premie))
I believe the problem has to do with casting. Why not write and extension method for IEnumberable which would take this query result and return a collection of List. It could look something like this:
public static class Extensions
{
// extends IEnumerable to allow conversion to a custom type
public static TCollection ToMyCustomCollection<TCollection, T>(this IEnumerable<T> ienum)
where TCollection : IList<T>, new()
{
// create our new custom type to populate and return
TCollection collection = new TCollection();
// iterate over the enumeration
foreach (var item in ienum)
{
// add to our collection
collection.Add((T)item);
}
return collection;
}
}
Thanks to kek444 for helping me with a similar problem