Hi,
I'm using LINQ to Entities on a database which structure is not known in advance. I use reflection to retrieve the information, and now have a list of strings with all the table names. Because I use LINQ, I also have the datasource encapsulated in a C# class (linqContext), with each table being a property of that class.
What I want...
I have a following tables/classes structure in Linq to entities.
Books
{
bookId,
Title
}
Tags
{
TagId
Tag
}
BooksTags
{
BookId
TagId
}
Now I need to write a query which gives me result like this
Class Result
{
bookId,
Title,
Tags
}
Tags should be comma separated text from the tags table by joining all three tables.
How...
var itemSet = from item in da.GetList<Models.account>()
join file in objFileStorageList
on item.account_id equals file.parent_id into objFile
from fileItem in objFile.DefaultIfEmpty()
where item.company != null && item.company.comp...
Scenario: Entity Framework 4 , POCO templates and Master Detail relation.
Lets say I have a master type like this:
//partial implementation of master entity
partial class Master
{
public void AddDetail(x,y,z)
{
var detail = new Detail()
{
X = x,
Y = y,
Z = z,
};
...
I am working on a website where a user can add tags to their posted books, much like is currently done for questions on Stack Overflow.
Classes:
Books
{
bookId,
Title
}
Tags
{
Id
Tag
}
BooksTags
{
Id
BookId
TagId
}
Here are few sample records.
Books
BookId Title
113421 A
113422 B
Tags
Id Tag
1 ASP
2 C#
3 CSS
4 VB
5 V...
Ex 1:
"autor.ComentariosWorkItens.Add(comentarioWorkItem);"
autor.ComentariosWorkItens makes EF4 load all ComentariosWorkItens.
Ex 2:
comentarioWorkItem.Usuario = autor;
Fixup make EF load all ComentariosWorkItens too:
private void FixupUsuario(Usuario previousValue)
{
if (previousValue != null && previousValue.Come...
Hi Experts,
I am working with linq to entities where I have a stored proc which returns an enetity based on some parameters. I can get this result in program. Now I want to join this resultset with similar entity on a common field.
my entity
Books
{
BookId,
Title
}
Stored Proc
GetFilterBooks(someparam)
(
Select * from books wher...
I've been playing with the O/R designer in VS and I was wondering if someone could shed come light on this. I'm used to OR mappers that are largely manual (homegrown and e.g., NHibernate). I don't mind encoding the entity classes myself, since they don't change all that often to begin with, and I have this irrational fear of designers an...
I'm tryring to do a simple insert with foreign key, but it seems that I need to use db.SaveChanges() for every record insert. How can I manage to use only one db.SaveChanges() at the end of this program?
public static void Test()
{
using (var entities = new DBEntities())
{
var sale =
new SalesFeed
...
I'm attempting to implement a repository pattern with my poco objects auto generated from my edmx.
In my repository class, I have:
IObjectSet<E> _objectSet;
private IObjectSet<E> objectSet
{
get
{
if (_objectSet == null)
{
_objectSet = this._context.CreateObjectSet<E>();
}
return _obj...
I have an Entity Framework 4.0 Entity Object called Revision w/ Nullable DateEffectiveFrom and DateEffectiveTo dates. I was wondering if there was a short-hand way of querying an object's RevisionHistory based on a particular QueryDate date instead of having to use the following query structure:
var results = EntityObject.Revisions.Wher...
The include does not work after I perform a select on the IQueryable query.
Is there a way arround this? My query is
public IQueryable<Network> GetAllNetworks()
{
var query = (from n in _db.NetworkSet
.Include("NetworkContacts.Contact")
.Include("NetworkContacts.Contact.RelationshipSource.Target")
...
I have a query as follows:
var query = from x in context.Employees
where (x.Salary > 0 && x.DeptId == 5) || x.DeptId == 2
order by x.Surname
select x;
The above is the original query and returns let's say 1000 employee entities.
I would now like to use the first query to deconstruct it and recreate a new query that would...
Hi,
When using Entity Framework with RIA domain services, domain services are inherited from LinqToEntitiesDomainService, which, I suppose, allows you to make LINQ queries on a low level (client-side) which propagate into ORM; meaning that all queries are performed on the database and only relevant results are retrieved to the server an...
Assuming these objects...
class MyClass
{
int ID {get;set;}
string Name {get;set;}
List<MyOtherClass> Things {get;set;}
}
class MyOtherClass
{
int ID {get;set;}
string Value {get;set;}
}
How do I perform a LINQ to Entities Query, using a projection like below, that will give me a List? This works fine with a...
Hello everyone,
I am trying to figure out how to go about writing a linq query to perform an aggregate like the sql query below:
select d.ID, d.FIRST_NAME, d.LAST_NAME, count(s.id) as design_count
from tbldesigner d inner join
TBLDESIGN s on d.ID = s.DESIGNER_ID
where s.COMPLETED = 1 and d.ACTIVE = 1
group by d.ID, d.FIRST_NAME, d.LAST_...
In EF v1 when we used GetObjectByKey on our context object contrary to linq query it stored queried object in cache is there any change in EF v2 (.NET 4) ?
...
Hello everyone,
I have the following LinqToEntities query, but am unsure of where or how to add the orderby clause:
var results =
from d in db.TBLDESIGNER
join s in db.TBLDESIGN on d.ID equals s.TBLDESIGNER.ID
where s.COMPLETED && d.ACTIVE
...
Hi,
what's the shortest way of returning an Entity Framework object from one table based on it's name attribute?
So say one had a table person, with column name, what would be the quickest way to return the person object with name = "Tim" say?
e.g. context.People.Select(m => m.Name == "Tim") doesn't seem to work?
...
Hi,
In entity framework is there a way to have a default value for a column such that Linq to Entity won't require this parameter when constructing a new object?
For example I've marked on column in the EF designer with a default value (I typed in "All" as it was a string). But if I try to construct a new record and not specify this p...