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robymes

How can I update the storage model from database?
I'm evolving the database schema in parallel with conceptual model, I know I can edit the storage model, but in some case it would be better to load updates directly from database (most of all for foreign keys constraints).

Thanks

robymes

When I want to enumerate all the types defined in the storage model I use the following query:

Code: Select all

var query = 
    from item in
    context.MetadataWorkspace.GetItems(DataSpace.SSpace)
    .Where(m => m.BuiltInTypeKind == BuiltInTypeKind.EntityType)
    select item;

I always get an exception. If I use DataSpace.CSpace (for conceptual model) the query works fine.

Thanks

robymes

Hello, I'm digging into ObjectContext.MetadataWorkspace.
everything is fine when I query the conceptual model via DataSpace.CSpace.
But I always receive an error when i query for the storage model via DataSpace.SSpace (exception says "System.InvalidOperationException: The space 'SSpace' has no associated collection").
Can you tell me something about this error?
Thanks

robymes

I haven't yet understand how Entity Developer works with code generation.
I have DataSourceModel.edml, so I also have DataSourceModel.cs and DataSourceModel.Designer.cs.
Why the two files contains the same code when I compile the model in Entity Developer? this is a problem when compiling in Visual Studio (ambiguos definitions).

Am I wrong somewhere?

Thanks

robymes

Guid in Oracle is RAW(16), if you set a primary key field in this way, when you update from the Entity Framework designer, automatically it recognizes the RAW(16) field type and will map it Guid in you entity class.

robymes

I have a very simple test

Code: Select all

[TestMethod]
public void TestMaxNumberOfObjectContetxtInTransactionScope()
{
	using (TransactionScope ts =
		this.GetTransactionScope(TransactionScopeOption.Required, IsolationLevel.ReadCommitted))
	{
		for (int i = 0; i < 33; i++)
		{
			using (TSObjectContext context = new TSObjectContext())
			{                    
				Guid id = Guid.NewGuid();
				string description = Guid.NewGuid().ToString();
				TestData newTestData = TestData.CreateTestData(id);
				newTestData.Description = description;
				context.AddToTestDataSet(newTestData);
				context.SaveChanges();
			}                    
		}
		ts.Complete();
	}
}

33 times is not a guess...
in direct=true mode it works (and it works even with a higher number of times: 200, 500, ...).
in direct=false mode it doesn't work: the maximum number of times is 32 (why 32???) to work properly
The error I get is: ORA-02045: too many local sessions participating in global transaction.
the connection string in direct=false mode refers to a configured service in tsnames.ora file (Oracle client configuration).
Why a so remarkable difference between the two?
I think it's unacceptable: the database is phisically the same, and there are scenarios in which i cannot use the direct=true connection mode (for example an Oracle RAC configuration in load balance, that needs a connection via tsnames.ora with a particular configuration).
I use the latest library (5.00.26).

robymes

you can also use a strategy with only one csdl (obviously) and msl+ssdl for sqlserver and oracle (5 files).

robymes

Hello,
I have a WCF service and I have a problem with TransactionScope when connection is not in direct mode (Direct=False).

I have something like this:

Code: Select all

TransactionOptions transactionOptions = new TransactionOptions();
transactionOptions.IsolationLevel = IsolationLevel.ReadCommitted;
transactionOptions.Timeout = new TimeSpan(0, 0, 30);
using (TransactionScope transactionScope = new TransactionScope(TransactionScopeOption.RequiresNew, transactionOptions))
{
    using (SomeObjectContext someObjectContext = new SomeObjectContext())
    {
        ...
        someObjectContext.SaveChanges();
    }
transactionScope.Complete();
}

when there are multiple concurrent threads it works only in direct=true connection mode, in direct=false connection mode all the transactions fail. It seems that in direct=false connection mode transactions are merged in some way even if TransactionScopeOption.RequiresNew flag.
Thanks for your support.

robymes

Thanks for the answer,
I'd like to know when will be available the next build: we have a great issue with this kind of problem and we need the new version as soon as possible.

Thanks

robymes

I have to make an update on what I say in the first post:
the exception is thrown not on ts.Complete(), but on disposing the TransactionScope.
The following test code do not use the "using" keyword and call the Dispose method:

Code: Select all

        [TestMethod]
        public void TransactionScopeWithSimpleInsert()
        {
            try
            {
                TransactionScope ts = null;
                try
                {
                    ts = new TransactionScope();
                    TSObjectContext context = null;
                    try
                    {
                        context = new TSObjectContext();
                        TestData testData =
                            context.TestDataSet
                            .First();
                        Guid id = Guid.NewGuid();
                        TestData newTestData = TestData.CreateTestData(id);
                        newTestData.Description = testData.Description;
                        context.AddToTestDataSet(newTestData);
                        context.SaveChanges();
                    }
                    catch (Exception)
                    {
                        throw;
                    }
                    finally
                    {
                        if (context != null)
                        {
                            context.Dispose();
                        }
                    }
                    ts.Complete();
                }
                catch (Exception)
                {
                    throw;
                }
                finally
                {
                    if (ts != null)
                    {
                        ts.Dispose();
                    }
                }
            }
            catch (Exception ex)
            {
                Assert.Fail(ex.Message);
            }
        }

On ts.Dispose() the provider throws the exception I quoted in the first post. The same code (without using keyword) works fine in SQLServer.

Thanks.

robymes

Hello,
I'm starting to think that TransactionScope has some problem with dotConnect for Oracle 5.00.20.
I have a very simple test in which I read an object and insert another one with the same description:

Code: Select all

        [TestMethod]
        public void TransactionScopeWithSimpleInsert()
        {
            try
            {
                using (TransactionScope ts = new TransactionScope())
                {
                    TSObjectContext context = null;
                    try
                    {
                        context = new TSObjectContext();
                        TestData testData =
                            context.TestDataSet
                            .First();
                        Guid id = Guid.NewGuid();
                        TestData newTestData = TestData.CreateTestData(id);
                        newTestData.Description = testData.Description;
                        context.AddToTestDataSet(newTestData);
                        context.SaveChanges();
                    }
                    catch (Exception)
                    {
                        throw;
                    }
                    finally
                    {
                        if (context != null)
                        {
                            context.Dispose();
                        }
                    }                    
                    ts.Complete();
                }                
            }
            catch (Exception ex)
            {
                Assert.Fail(ex.Message);
            }
        }

this test throw an exception on ts.Complete():

The operation is not valid for the current state of the enlistment.

System.InvalidOperationException
at System.Transactions.EnlistmentState.ForceRollback(InternalEnlistment enlistment, Exception e)
at System.Transactions.PreparingEnlistment.ForceRollback()
at Devart.Data.Oracle.h.a(PreparingEnlistment A_0)
at System.Transactions.VolatileEnlistmentPreparing.EnterState(InternalEnlistment enlistment)
at System.Transactions.VolatileEnlistmentActive.ChangeStatePreparing(InternalEnlistment enlistment)
at System.Transactions.TransactionStateVolatilePhase1.EnterState(InternalTransaction tx)
at System.Transactions.TransactionStatePhase0.EnterState(InternalTransaction tx)
at System.Transactions.TransactionStateActive.BeginCommit(InternalTransaction tx, Boolean asyncCommit, AsyncCallback asyncCallback, Object asyncState)
at System.Transactions.CommittableTransaction.Commit()
at System.Transactions.TransactionScope.InternalDispose()
at System.Transactions.TransactionScope.Dispose()
at TestDevArtTransatcionScope.TestSuite.TransactionScopeTestCase.TransactionScopeWithSimpleInsert()

the same test works without any problem with SQLServer, and honestly I don't see any reason why it shouldn't work.
Why it fails with Oracle?
This is a very simple test, am I wrong somewhere?

Thanks.

robymes

Just a few details:
the problem isn't the SID name, the SID is correct, the connection is in direct mode.
The problem, more precisely, is:
in a transaction scope everything goes well until the number of queries is low, if the number of queries increases (there's no rule about how many), the provider starts to raise the invalid sid exception.
with query I mean a using statement with a new objectcontext (so in the transaction scope you have several times a creation and a dispose of an objectcontext).
As you suggest I sent you an email with the project

Thanks

robymes

Hello,
Entity Framework based on dotConnect for Oracle 5.00.20, Oracle Express 10g, Windows 2003 Server, DTC service.
I have a WCF service method that starts a transaction with TransactionScope.
During transaction it recalls several other services that start an ObjectContext each. I receive always an exception which says "NET: Invalid SID".
I made a small project with a test to reproduce the situation, and I got always the same error: during transaction, after some ObjectContext creations, at SaveChenges it seems the provider cannot open the connection and throws that exception.

Thanks

robymes

Hello,
I understand why the SP disappeared: I took a look into the xml of edmx file and I found:

Errors Found During Generation: warning 6005: The function 'CREATESECTION' has a parameter 'V_MENUVISIBILITY' at parameter index 5 that has a data type 'PL/SQL BOOLEAN' which is not supported, the function was excluded.

I have to say:
first, BOOLEAN is perfectly legal in PL\SQL, even if there's no such data type name for table fields, boolean in table fields must be NUMBER(1,0)
second, the SP mapped for CRUD, with BOOLEAN in parameters, works perfectly with your data provider for EF, so I don't understand why the designer alerts an error this way.

thanks

robymes

Thanks,
where I can provide you sql scripts?

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