EF4 POCO & Devart

[Alladin]

Hello there,

I'm trying to engage new feature of EF4 called code-only configuration.

Using ContextBuilder class from Microsoft.Data.Entity.CTP assembly.

However ObjectContext produced by ContextBuilder.Create with OracleCommand as connection, produces MSSQL-based context.

So my all selects look like this:

Code: Select all

SELECT 
"Extent1"."courseid" AS "courseid", 
"Extent1"."price" AS "price", 
"Extent1"."title" AS "title"
FROM "dbo"."course" "Extent1"

What am I doing wrong or does DevArt EF4 provider support EF4 code-only configuration?

PS. To moderator, could you please move this post to Entity Framework forum?

[AndreyR]

We are investigating the situation.
I will let you know about the results.

[ghostknight]

The "dbo" issue is on the EF4 side. I've described it here http://social.msdn.microsoft.com/Forums ... d55f890d61

They promise to fix it before release.

And enclosing identifiers in quotes is definitely dotConnect's issue
I've posted investigation here:
http://www.devart.com/forums/viewtopic. ... 5665#55665

[AndreyR]

The Code Only functionality was not added into Entity Framework v4 RTM.
Existing EF CTP 3 works with EF v4 RTM but has some known compatibility issues, for example some DB Generation issues, table mapping customization problems, the "dbo" bug etc.
However, we have found a workaround for the problems like the one you've encountered. First we are creating a custom MyTable class:

Code: Select all

  public class MyTable {
    public int Id { get; set; }
    public string F_String { get; set; }
  }

Here is the usage example:

Code: Select all

     var builder = new ContextBuilder();

      builder.Entity()
        .HasKey(a => a.Id)
        .MapSingleType(a => new {
          ID = a.Id,
          F_STRING = a.F_String 
        })
        .ToTable("SCOTT.MY_TABLE");

      OracleConnection con = new OracleConnection("User Id=scott;Password=tiger;Server=ORA;");
      ObjectContext context = builder.Create(con);

      ObjectSet MyTables = context.CreateObjectSet();
      var allMyTablesQuery = from it in MyTables
                             where it.Id < 10
                             orderby it.Id
                             select it;

      string sql = (allMyTablesQuery as ObjectQuery).ToTraceString();

The SQL generated:

Code: Select all

      SELECT 
      "Extent1".F_STRING AS F_STRING, 
      "Extent1".ID AS ID
      FROM SCOTT.MY_TABLE "Extent1"
      WHERE "Extent1".ID < 10
      ORDER BY "Extent1".ID ASC

[ghostknight]

Great! Thanks, will try it... I've also foun another solution, but it doesn't go for production, only suiteable for testing|investigation purposes...

I'll try your solutuion.

Thanks a lot again!

[Alladin]

Does not work.

If you specify ToTable("nitro.TPORTFOLIOS"), insert SQL generated looks like this:

insert into "nitro".TPORTFOLIOS("Active", "ClosingTime", "clsid", "CreationTime", "Definition", "Description", "Id", "Name", "parent", "PublicId", "Tsid", "Type")
values (:p0, null, :p1, null, null, :p2, :p3, :p4, null, null, :p5, :p6)

Schema name is NITRO.

"ORA-00942: table or view does not exist"

To fix this problem, in generate SQL devart should:

1) Remove quotes in schema name (at least, or eliminate default dbo prefix).
2) Remove quotes in column names.

[AndreyR]

Please try to use the correct schema name, like here:

Code: Select all

.ToTable("NITRO.MY_TABLE");

As for the column names, please try to specify the column names in the correct case in your model, mapping is appropriate to the names of your properties.

[ChrisD]

Hello,

I'm currently evaluating Code First (CTP 4) with POCO-classes for a project. In combination with Microsoft SQL Server, it works like a charm.

To connect to a local MySQL-server (v5.5.5 m3) I'd like to use the current dotConnect for MySQL to create the database scheme from my model. With CreateDatabaseScript(), I only get the "Creating all foreign keys" part in the DDL-script.

For example:

Code: Select all

ALTER TABLE dbo.DeviceConfigurations
  ADD CONSTRAINT FK_DeviceConfiguration_Device FOREIGN KEY (DeviceId) REFERENCES dbo.Devices (DeviceId)
  ON DELETE CASCADE ON UPDATE NO ACTION;

In general I can understand when there's not a total support for the unfinished Code First feature yet. But shouldn't the CreateDatabase-methods use the MetadataWorkspace-part of the Entity Framework to create the DDL-script?
Looking at the entries in the StoreItemCollection of the SSpace I don't see any difference between the configuration comparing code-based and model-based.

Thank you for time,

Christian

[AndreyR]

We are in the process of CTP 4 testing.
Could you please specify the message of the error you have encountered?

[ChrisD]

The initial error is a MySqlException (Table 'dbo.deviceconfigurations' doesn't exist) when trying to call CreateDatabase() on my model-instance.

This is perfectly clear when we consider the string that I'll get from CreateDatabaseScript() that is applied when using CreateDatabase() (see above).

Because there is only the constraint-definition in the script, the expected tables (in this case 'deviceconfigurations') have not been created beforehand, therefore causing this exception.

I've rechecked the Meta-information of the model and the entity-definitions for the tables are present (probably identical to model first). That's why I'm wondering if the Meta-information is wrongly presented with the new CTP4 or the script-creation in general is faulty.

ChrisD

[AndreyR]

Thank you for the information. Our testing is in progress, I will post here about the results.