The reason is that the line

query.ToList();

performs an immediate execution of the query.

This is true for other clauses such as First(), FirstOrNullEntity(), FirstOrDefault(), etc.

 

 

 

The specified type member 'Name' is not supported in LINQ to Entities. Only initializers, entity members, and entity navigation properties are supported.

 

is the error I get when doing this

 

BindableList<Customer> _bl = new BindableList<Customer>();
BindingSource _bs = new BindingSource();
_bs.DataSource = _bl;

       var qry =_entityManager.Countries
==>            .Where(c => c.Name.Contains(pValue));

 

_bl.ReplaceRange(qry.ToList());

 

 

what is the reason for this ? I cannot use "Name" as an entity property ?

BindableList<Employee> _bl = new BindableList<Employee>();
            BindingSource _bs = new BindingSource();
            _bs.DataSource = _bl;
            IEntityQuery<Employee> qry = (IEntityQuery<Employee>)_entityManager.BasePersons
                .Include(Employee.PathFor(b => b.Address))
                .Include(Employee.PathFor(b => b.Address.Country))
                .Where(b => b.Name.Contains(pValue))
                                ;

            _bl.ReplaceRange(qry.ToList().OfType<Employee>()
);

 

I changed to this and it works fine, why ?

 

Can somebody explain this to me ?

 

 BindableList<Employee> _bl = new BindableList<Employee>();
            BindingSource _bs = new BindingSource();
            _bs.DataSource = _bl;
            IEntityQuery<Employee> qry = (IEntityQuery<Employee>)_entityManager.BasePersons
                .Include(Employee.PathFor(b => b.Address))
                .Include(Employee.PathFor(b => b.Address.Country))
                .Where(b => b.Name.Contains(pValue))
                .OfType<Employee>()
                ;

            _bl.ReplaceRange(qry);

 

where Employees are inherited from BasePersons

 

the sql query does not perform the include (there is no join in the sql statement) so the application ends up fetching all Addresses one by one

 

when doing this query for all basepersons then it is ok

 

What is the problem here ?