.NET Core 3 Support

[pbros]

Hello,

What is the expected timeline for .NET Core 3 support now that it has been officially released?

Thank you

[alexkeh]

Oracle is currently running its .NET Core test suites against ODP.NET Core. We plan to release a new version that is .NET Core 3 certified on the NuGet Gallery in the next couple weeks, plus or minus. It's hard to give an exact timeline as we don't know what testing will find until we find issues, then fix them.

[pbros]

Do you know if the next release will also support ASP.Net Identity?

[alexkeh]

No, the release coming up in about a week or so will not have ASP.NET Identity support.

[lordkyuusei]

Hey!
Anything new since the last two weeks regarding .NET Core 3 support? I believe that this is a highly anticipated update for developers that wish to upgrade their oracle-db .net apps.

[alexkeh]

We're finishing up our testing this week. The release is planned for next week if no major showstoppers come up.

[0x4Graham]

Hey,

Would supporting .net core 3 fix an issue I am having when connecting to Oracle DB?

OraBufWriter:ReadResetResponse - Unexpected Packet received

ORA-04088: error during execution of trigger 'SYSTEM.LOGONTRG'.ORA-00604: errorred at recursive SQL level 1.

ORA-06502: PL/SQL: numeric or value error: character string buffer too small.

ORA-06512: at "SYSTEM.LOG_SESSION_INFO", line 38.ORA-06512: at line 2.

The issue I am having is rather interesting though. When running the application on my local, it can connect to the DB perfectly even though when I am using .NET Core 3.

But when I deploy to our Kubernetes instance I get the above error.

[alexkeh]

@grey007

Most likely, you are encountering a Kubernetes-specific related issue, not one related to .NET Core 3. Oracle hasn't seen an issue similar to yours in testing in a non-Kubernetes environment either. OTOH, we have seen a bug similar to yours in .NET Core 2 that was also running in Kubernetes.

[alexkeh]

ODP.NET Core 19.5 has just been released. This new version supports .NET Core 3.
https://www.nuget.org/packages/Oracle.ManagedDataAccess.Core/

[CJ18874]

Still not working with .NET Core 3. Any temporary workaround?

[alexkeh]

How is ODP.NET Core not working in .NET Core 3? Please share as much error info as you can. Otherwise, it's impossible to advise on a workaround.

[CJ18874]

PM> Scaffold-DbContext "User Id=<>;Password=<>;Data Source=<>/<>;" Oracle.EntityFrameworkCore -OutputDir Models
System.TypeLoadException: Method 'Create' in type 'Oracle.EntityFrameworkCore.Scaffolding.Internal.OracleDatabaseModelFactory' from assembly 'Oracle.EntityFrameworkCore, Version=2.0.19.1, Culture=neutral, PublicKeyToken=89b483f429c47342' does not have an implementation.
at Oracle.EntityFrameworkCore.Design.Internal.OracleDesignTimeServices.ConfigureDesignTimeServices(IServiceCollection serviceCollection)
at Microsoft.EntityFrameworkCore.Design.Internal.DesignTimeServicesBuilder.ConfigureDesignTimeServices(Type designTimeServicesType, IServiceCollection services)
at Microsoft.EntityFrameworkCore.Design.Internal.DesignTimeServicesBuilder.ConfigureProviderServices(String provider, IServiceCollection services, Boolean throwOnError)
at Microsoft.EntityFrameworkCore.Design.Internal.DesignTimeServicesBuilder.Build(String provider)
at Microsoft.EntityFrameworkCore.Design.Internal.DatabaseOperations.ScaffoldContext(String provider, String connectionString, String outputDir, String outputContextDir, String dbContextClassName, IEnumerable1 schemas, IEnumerable1 tables, Boolean useDataAnnotations, Boolean overwriteFiles, Boolean useDatabaseNames)
at Microsoft.EntityFrameworkCore.Design.OperationExecutor.ScaffoldContextImpl(String provider, String connectionString, String outputDir, String outputDbContextDir, String dbContextClassName, IEnumerable1 schemaFilters, IEnumerable1 tableFilters, Boolean useDataAnnotations, Boolean overwriteFiles, Boolean useDatabaseNames)
at Microsoft.EntityFrameworkCore.Design.OperationExecutor.ScaffoldContext.<>c__DisplayClass0_0.<.ctor>b__0()
at Microsoft.EntityFrameworkCore.Design.OperationExecutor.OperationBase.<>c__DisplayClass3_0`1.b__0()
at Microsoft.EntityFrameworkCore.Design.OperationExecutor.OperationBase.Execute(Action action)
Method 'Create' in type 'Oracle.EntityFrameworkCore.Scaffolding.Internal.OracleDatabaseModelFactory' from assembly 'Oracle.EntityFrameworkCore, Version=2.0.19.1, Culture=neutral, PublicKeyToken=89b483f429c47342' does not have an implementation.
PM>

[alexkeh]

@CJ18874 EF Core 3 is not supported yet. Only .NET Core 3 is supported. EF Core 3 requires a new implementation from provider writers, which is what the Oracle team is working for its next EF Core version.

[alexkeh]

The workaround is to use EF Core 2.

[LucaGabi]

How can I use EF Core 2 ?

I have to downgrade from dotnet core 3 ?

[alexkeh]

@LucaGabi You can create a .NET Core 3 project, then add the Oracle EF Core 2 assembly, which will pull in EF Core 2 dependencies.

[iAmBipinPaul]

any expected date , when EF Core 3 support will be available ?

[alexkeh]

@iAmBipinPaul My personal best guess is April for the beta. I'm hoping in the early part of the month. As the dev team has fixed the bugs found, the remaining ones are fewer, but harder to resolve. There is no specific date we're trying to meet. We're working through the key issues as quickly as possible.

Oracle EF Core 3 has a feature bound release target, not a time bound target. In a time bound scenario, the product ships on a specific date. Any features that don't meet a completeness or quality control threshold by then are removed/disabled from the release. The remaining features ship.

In a feature bound target, the product ships only when the completeness and quality control thresholds are met. For example, you don't want 10% of your LINQ to generate invalid Oracle SQL. You need that to be as close to 100% as possible.

A framework like EF Core has the additional complication that it isn't a typical API such that each provider writer picks and chooses the classes and class members to implement; each API accomplishes a generally simple, discrete task; and the customer has the choice to use each individual API or not.

The provider writer has to support all of LINQ, all its behavior when a customer composes an arbitrary LINQ statement, and execute it in a highly performant manner.

[iAmBipinPaul]

Okay , Thank you for the explanation.
I'm trying to connect to Oracle free autonomous database from EF core 2.2 and i'm getting this erro.

2020-02-29 09:05:33.304378 ThreadID:1   (ERROR)   OracleDatabaseCreator.Exists() :  OracleException.Number: 12537
2020-02-29 09:05:33.307641 ThreadID:1   (ERROR)   OracleDatabaseCreator.Exists() :  Oracle.ManagedDataAccess.Client.OracleException (0x80004005): ORA-12537: Network Session: End of file
 ---> OracleInternal.Network.NetworkException (0x000030F9): ORA-12537: Network Session: End of file
   at OracleInternal.Network.OracleCommunication.DoConnect(String tnsDescriptor)
   at OracleInternal.Network.OracleCommunication.Connect(String tnsDescriptor, Boolean doNAHandshake, String IName, ConnectionOption CO)
   at OracleInternal.ServiceObjects.OracleConnectionImpl.Connect(ConnectionString cs, Boolean bOpenEndUserSession, OracleConnection connRefForCriteria, String instanceName)

Connection String format

 "ConnectionString": "User Id=ADMIN;Password=Password;Data Source=<adb....>.oraclecloud.com;"

so basically how to connect from these connection strings

Thank you :) !

[alexkeh]

@iAmBipinPaul
See #59 (comment)

[alexandis]

I have similar error message, but in late 2020 with different DLL version:

TypeLoadException: Method 'Create' in type 'Oracle.EntityFrameworkCore.Query.Internal.OracleQueryableMethodTranslatingExpressionVisitorFactory' from assembly 'Oracle.EntityFrameworkCore, Version=3.1.19.1, Culture=neutral, PublicKeyToken=89b483f429c47342' does not have an implementation.

Running netcoreapp3.1 host. I've checked the DLL in reflector and of course the method is in place. So have no idea what this error means...

[alexkeh]

Usually this occurs if one of your assemblies require EF Core 5 reliant, such as a newer version of Microsoft.EntityFrameworkCore.Tools. The runtime may be .NET Core 3.1, but all the loaded assemblies have to be able to use EF Core 3.1 and .NET Core 3.1 as well.

[alexandis]

Usually this occurs if one of your assemblies require EF Core 5 reliant, such as a newer version of Microsoft.EntityFrameworkCore.Tools. The runtime may be .NET Core 3.1, but all the loaded assemblies have to be able to use EF Core 3.1 and .NET Core 3.1 as well.

Hmm.. Thank you. But is there some troubleshooting instrument to find the root cause? The truth is I have a lot of dependencies in the project, also it references another projects (they are netstandard2.1) in the solution as well as 3rd party framework (ABP)...

[alexkeh]

You are using Microsoft.EntityFrameworkCore 5.0. Try downgrading that to version 3.1.x and running the app again.

[alexandis]

@alexkeh You are amazing! It works now! Without your help I'd be stuck for a while. Thank you very much.

[marcofacchetti]

Hi alexkeh I have the same problem with my application. i migrated from netcore 2.2 to 3.1 and had no problems.
Now I have upgraded to net 5.0 version but I get this error when creating the dbcontext

System.TypeLoadException: Method 'Create' in type 'Oracle.EntityFrameworkCore.Query.Internal.OracleQueryableMethodTranslatingExpressionVisitorFactory' from assembly 'Oracle.EntityFrameworkCore, Version = 3.1.19.1, Culture = neutral, PublicKeyToken = 89b483f429c47342.

Do you have any suggestions

[alexkeh]

@marcofacchetti EF Core 5 isn't supported yet. We're working on releasing the Oracle EF Core 5 provider by the end of this month.

[hnoerdli]

You are using Microsoft.EntityFrameworkCore 5.0. Try downgrading that to version 3.1.x and running the app again.

This solved my problem too.