Devart Forums

JoeRuspante

Hi everybody.
I see that DotConnect for Oracle supports Outer Apply in EF6 with Oracle 12c.

Is the same problem solved also on DotConnect for MySql

JoeRuspante

Hi everybody.

I have a simple model Class:

Code: Select all



    [Table("USER_TEST")]
    public class User
    {

        public long Id { get; set; }

        public string Name { get; set; }

    }

Then I have my DbContext with this settings:

Code: Select all


public class MyContext : DbContext
{

    public MyContext()
        : base("MyConnectionString")
    {
        InitializeOracle();
    }

    private void InitializeOracle()
    {
        OracleEntityProviderConfig.Instance.CodeFirstOptions.UseNonUnicodeStrings = true;
        OracleEntityProviderConfig.Instance.QueryOptions.CaseInsensitiveLike = true;
        OracleEntityProviderConfig.Instance.Workarounds.IgnoreSchemaName = true;
        OracleEntityProviderConfig.Instance.Workarounds.IgnoreDboSchemaName = true;
        OracleEntityProviderConfig.Instance.CodeFirstOptions.TruncateLongDefaultNames = false;
        OracleEntityProviderConfig.Instance.CodeFirstOptions.UseDateTimeAsDate = true;
        OracleEntityProviderConfig.Instance.Workarounds.DisableQuoting = true;
        OracleEntityProviderConfig.Instance.Workarounds.ColumnTypeCasingConventionCompatibility = true;
        }

    protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
        Database.SetInitializer<MyContext>(null);
        modelBuilder.Conventions.Remove<PluralizingTableNameConvention>();
        modelBuilder.Conventions.Remove<ColumnTypeCasingConvention>();
        modelBuilder.Conventions.Remove<OneToManyCascadeDeleteConvention>();
        base.OnModelCreating(modelBuilder);
    }

    public DbSet<User> Users { get; set; }

}

Now I try to add 1.000 users to the db:

Code: Select all


MyContext ctx = null;
try
{
   ctx = new MyContext();
   ctx.Configuration.ValidateOnSaveEnabled = false;
   for (int i = 0; i < 1000; i++)
   {
      User u = new User();
      u.Name = "User" + i.ToString();
      ctx.Users.Add(u);
   }
   ctx.SaveChanges();
}
finally
{
   if (ctx != null)
   {
      ctx.Dispose();
      GC.SuppressFinalize(ctx);
   }
}

I don't know why, but that code requires about 18 seconds to run. How can I make it faster?
If I do it by hand (OracleConnection + OracleCommand) it takes about 2.5 seconds...

I'm using:
- .Net framework 4.5
- Devart 7.4.146

JoeRuspante

Hi everybody.

I saw that EntityFramework is now Open Source, so anybody could help to resolve the "OuterApply not supported by Oracle" problem.

Do you plan to help Microsoft to solve this issue? (maybe better say "convince Microsoft to do it")

I also saw that now EF6 (beta) has a kind of Interceptor... Maybe you could implement that interceptor for convert the "OuterApply" to another query that the DB could execute.

This is the link: https://entityframework.codeplex.com/wi ... terception

I know that the best way will be done by Microsoft using standard SQL, but since Microsoft sells SQL, maybe isn't interessed in that problem.
So, if you can do it throw any kind of way (for example with Interceptor), why can't you try to do it?

Thank you in advance.

JoeRuspante

Thank you, but we need some functionalities that express does not support (EF and Direct mode).

So we think to create a custom NuGet server (internal to our site), so we can use it for all projects. The problem that we have is the licence.

Now we can use DotConnect without have installed it, need only a "licx" file + additional file generated by the "lc" command (we read it on the licencing tutorial of devart).

The problem is that we use it in more project. There is a way to create a "licx" file (and additional license file) that doesn't need the name of the assembly? So we can generate a NuGet package that contains DLL and licence files without create a package for each solution.

Thank you in advance

JoeRuspante

We did the backend without using designers or Visual Studio integrations.
We only need the runtime dll (included in the project, nothing more).

What do you suggest? Can we use the "Express" version for have the NuGet functionality? Or bux-fixes will arrive later on this version?

Of course, we will continue to buy licences for the support, but have a NuGet server will help us a lot.

Thank you in advance

JoeRuspante

Hi everybody.

I'm using dotConnect for Oracle 7.4.142 and EntityFramework Code First (Runtime 4.5).
In a solution I'm reading xml files from a directory and update an Oracle's table.

This is a simply code:

Code: Select all


MyDbContext ctx = new MyDbContext();
foreach (var item in Directory.GetFiles(@"mydir", "*.xml")
{

   Customer c = new Customer();
   // Loading data into c variable from xml file
   ctx.Customers.Add(c);
   using (TransactionScope t = new TransactionScope())
   {
      ctx.SaveChanges();
      t.Complete();
   }

}

When I have a lot of files to elaborate in a same execution, the programm exit with "ORA-8177" error.

It seems a problem of the IsolationLevel used.

How can I change it?

PS: On MyDbContext I make some configurations by code...

Code: Select all



OracleEntityProviderConfig.Instance.CodeFirstOptions.UseNonUnicodeStrings = true;
OracleEntityProviderConfig.Instance.Workarounds.IgnoreSchemaName = true;
OracleEntityProviderConfig.Instance.Workarounds.IgnoreDboSchemaName = true;
OracleEntityProviderConfig.Instance.CodeFirstOptions.TruncateLongDefaultNames = true;
OracleEntityProviderConfig.Instance.CodeFirstOptions.UseDateTimeAsDate = true;
OracleEntityProviderConfig.Instance.Workarounds.DisableQuoting = true;
OracleEntityProviderConfig.Instance.Workarounds.ColumnTypeCasingConventionCompatibility = true;

JoeRuspante

If I understood, EF passes an Expression Tree.

So it has to tell to the provider that the query needs 2 fields from the table.
But, who write the query?

Because the generated query is something like that:

Code: Select all


SELECT Extent1.Name,
       Extent2.Surname
FROM Customer C
     JOIN CustomerDetails Extent1 ON ( C.CustomerDetailsId = Extent1.Id)
     JOIN CustomerDetails Extent2 ON ( C.CustomerDetailsId = Extent1.Id)

So, is EF4.5 that generate the query with this unnecessary joins? Or does your provider receive a tree and converts it in this query?

It's only for understand. I thought your driver writes the query and not EF4.5 (wrote by Microsoft and that won't work with Oracle)

JoeRuspante

I'm interested in the Linq Insight tool.

Is it possible to use it with code first + dotConnect for Oracle?

If so, does it support the fact that in my solution I have a project with only the data model (class object) and another one with only the DbContext (so DbContext and class definitions are in two differents assembly/projects).

Thank you in advance

JoeRuspante

There is a workaround for use a LINQ that throws teh "OUTER APPLY NOT SUPPORTER BY ORACLE" exception?

I saw the workaround when I need only a field (ex: min(date)).
In my case I have an order with more details (1 to N relationship) and I need to have all the data of the first detail row (quantity, price, ...)

My LINQ query is this:

Code: Select all


var query = from o in MyContext.Orders
            let d = o.Details.OrderBy(x => x.Id).FirstOrDefault()
            select new OrderDTO
            {
                Id = o.Id,
                ProductId = d.ProductId,
                Price = d.Price
                Quantity = d.Quantity
            }

Thank you in advance

JoeRuspante

For now I founded a workaround using the "let" clause.
But I think it's not common use the "let" for all descendants relationship.

I hope you will give me a solution as soon as possible

JoeRuspante

Hi everybody.

I'm working with the latest version of DotConnect for Oralce and I have this model:

Code: Select all


public class Order
{
    public int Id {get;set;}
    public int Number {get;set;}
    // Other properties

    // Relationship with Customer
    public int CustomerId {get;set;}
    public Customer Customer {get;set;}
}

public class Customer
{

    public int Id {get;set;}
    // Other properties

    // Relationship with CustomerDetails
    public CustomerDetails Details {get;set;}
}


public class CustomerDetails
{

    public int Id {get;set;}
    public string Name {get;set;}
    public string Surname {get;set;}
}

Now I have a method that need a single object CustomerDTO done in this way:

Code: Select all



public class CustomerDTO
{
    // From Customer
    public int Id {get;set;}

    // From CustomerDetails
    public string Name {get;set;}
    public string Surname {get;set;}
}

Now I extract all orders with this query linq:

Code: Select all


var query = MyDbContext.Orders
                .Include(x => x.Customer)
                .Include(x => x.Customer.Details)
                .Select(x => new OrderDTO
                      {
                         // Order properties
                         Customer = new CustomerDTO
                         {
                             Id = x.Customer.Id,
                             Name = x.Customer.Details.Name,
                             Surname = x.Customer.Details.Surname
                         }
                      }
                );

Looking with DbMonitor the query, I saw that the join between Customer and CustomerDetails occurs two times (one for each field taken from x.Customer.Details object).
If I took only the Name, the join appears only 1 time.
If I took Name, Surname and Address, it occurs 3 times.

Why?

JoeRuspante

Thank you very much

JoeRuspante

Hi everybody.

I have a problem with DateTime properties (.NET DateTime).
Using dotConnect for Oracle, it maps DateTime property on Oracle TIMESTAMP data type.

My problem is that I have another application that doesn't work with TIMESTAMP Oracle data type. It needs "DATE" type.

I tried to change the data type on the DB (manually), and I see that both applications will work (in our application, the user can insert at max minutes, so I don't lost any information).

So I'd like to know if there is any kind of setting that let me inform dotConnect to map DateTime property on Oracle DATE type instead of TIMESTAMP.
I don't want to do it for each property (like data attribute or special configuration for every property in the "OnModelCreating" event).

Thank you in advance.

JoeRuspante

I found the problem.

On Visual Studio I have 2 rows for each DLL.
If I use the first one, it won't work.
If I use the second one, it works...

Is it possible to know why I have 2 voices for each dll (and 1 don't work)?

JoeRuspante

Hi.

I passed to the new version of dotConnect for Oracle and my solution now don't compile because don't find the OracleEntityProviderConfig.

If I try to write all the string by hand "Devart.Data.Oracle.Entity.Configuration" I found only "a, b, c" classes and not OracleEntityProviderConfig...

What's wrong?
The code I had could compile on the previous version of dotConnect (7.1.xx)

Thank you in advance

Devart Forums

Search found 54 matches

outer apply

Slow insert

EF6 - OpenSource - OuterApply

Re: NuGet

Re: NuGet

ORA-8177

Re: Strange Include query

Is it possible to use it with code first + dotConnect for Oracle

OUTER APPLY WORKAROUND

Re: Strange Include query

Strange Include query

Re: DateTime mapping CodeFirst

DateTime mapping CodeFirst

Re: OracleEntityProviderConfig on 7.2.77.0

OracleEntityProviderConfig on 7.2.77.0