Entity Framework 6 (5) connection to Oracle - visual-studio-2013

I am attempting to write a Data Access library for our suite of applications that use Oracle in .net. We currently use NHibernate and are thinking of migrating away as it appears to not be supported all that well.
I am working with Visual Studio 2013 and we have already constructed our Oracle Database. We don't have writes to update it (that is the domain of the db guys). So that will not be part of any calculation on our end.
The client on the server is 32 bit, so we are going to stick with that for now. It is already GAC'd in there, and no need to change it. So we have the 32 bit client on our development boxes.
I have EntityFramework 6.1.0 installed into my project via nuget. I have ODAC 1.112.3.20 installed in my project. The 32bit version of the application. I also have the ODP.net.x86 driver installed (also via nuget).
The problem is that everytime I attempt to create an ADO.net Database connection, the oracle provider is never an option? What am I missing? What do I need to get this to work?
I read an oracle forum one time that said I need to set my Entity Framework to 5.0 and not 6.0. Which is fine, but how do I do that?

EF 6 support is now provided by ODAC 12c Release 3 Beta:
From the .Net Developer newsletter (emphasis mine):
New Download: ODAC 12c Release 3 Beta The new ODAC beta includes
Entity Framework 6, Code First, Code First Migrations, .NET Framework
4.5.2 certification, managed ODP.NET XML DB, and managed ODP.NET distributed transaction support without Oracle.ManagedDataAccessDTC.dll.

I know this is getting a little old, but this is to answer the last part of your question (how to install EFv5). (Instructions written for VisualStudio 2013) with your solution open, click TOOLS->NuGet Package Manager->Package Manager Console. Enter the following:
Install-Package EntityFramework -Version 5.0.0
Edit
It’s been a while since I set up my machine, but I think this is what I had to do, hopefully it helps.
Setup:
Install Oracle Instant Client (or whatever you do for an Oracle Home)
Install ODTwithODAC121012 (if you Google that, it should come up)
Make sure your tnsnames.ora is in the right place for your Oracle Home
Setting up a new Visual Studio Solution:
New Solution (for me, of type ASP.NET Web Application)
Run command as in original answer
Add new project of type Class Library (for Model/Entities)
In new project, add new Item of type ADO.NET Entity Data Model
In Entity Data Model Wizard:
EF Designer from database (if you are using an existing database)
New Connection
In Data Source, there is (hopefully) an Oracle Database option
And below that, in data provider, I chose the ODP.NET Managed Driver
Enter user/pass, select Data Source and name connection
Edit 2
Oh, I forgot one thing, not sure if it's important. You may need to add a reference in that Model project to the oracle driver. Right click project -> Add -> Reference -> Assemblies -> Search for 'oracle', hopefully there is an entry for Oracle.ManagedDataAccess (my version was 4.121.1.0)
A few rants:
I don't think the process should be quite so difficult
I don't know why it takes them so long to update either. http://www.devart.com/ seems to do just fine staying on top of new Oracle/Visual Studio changes (they charge, but so does Oracle)
The conspiracy part of my brain says that Oracle has no interest in making it easier for you to not use their products and so they put no effort into it
Their default number mappings can really screw you up. For example, if your Oracle DB has fields of type NUMBER(10), it will map it as a 32-bit int, when not all 10 digit numbers fit :(
For more info on that mapping thing (the link shows how to override that 32-bit problem), see:
http://docs.oracle.com/cd/E56485_01/win.121/e55744/InstallConfig.htm#ODPNT8167

EF 6 is not yet supported by ODP.NET. See the release notes (README) for more info. EF6 will be supported shortly.
Edit: EF6 is now supported.

Sorry, I missed part of your question.
If you are using Visual Studio 2013, you must download Oracle Developer Tools for Visual Studio version 12.1.0.1.2 or later. With any older version, it will not be able to integrate with VS 2013.
Here is the download location:
http://www.oracle.com/technetwork/topics/dotnet/utilsoft-086879.html
EF 6.0 is not supported yet but you can use EF5 providers in VS 2013. So my other answer is not really relevant.

Entity Framework 6 Code First
ODAC 12c R3 is the first ODP.NET release to certify with Entity
Framework (EF) 6 and EF Code First. EF Code First is a popular
development model for .NET object-relational mapping. Developers
define the application domain model using source code, rather than
with a designer or an XML-based configuration file. An EF Code First
model's classes are defined in code through Plain Old CLR Objects
(POCOs).
...
These features are all available in both managed and unmanaged
ODP.NET.
http://cshay.blogspot.com/2014/09/odac-12c-release-3-beta-now-available.html

Related

Cannot find ADO.Net in VS2022 Community Edition

I've recently started using VS2022 Community Edition Version 17.4.4 after using VS2017 Enterprise Edition for many years. I've started a new project after selecting ASP.Net Core Web App using MVC. After creating the project, I used Nuget to import the MS.EntityFramwork packages I need and the went to add a new item to select ADO.Net from my DB for my Entity Framework. However, as you can see from the screenshot below the packages are there but ADO.Net is not.
Although I cannot find ADO.Net I can select Scaffolding if I want to and something tells me that is the only option available to me. I've used this process of adding Entity Framework many times and I think it's no coincidence that it isn't available after updating my Visual Studio. Can someone please confirm this is my only option to work with my SQL database or is there something I'm missing in order to access ADO.Net.
ADO.Net only works with .Net Framework. You can pay attention to see what your framework version is. If it is .Net XXX, it should be that you have created the wrong project, and the type of project you should create is ASP.Net Web Application (.Net Framework).
If following the methods above doesn't work, please speak up.

Generating a model from an Oracle 18c database in EntityFramework

I am using VS 2017, ODAC for VS 2017, and Oracle.ManagedDataAccess 12.2.1100 (and its corresponding EF dll), and EF 6.4.
The database is 18c Express, and is running on a virtual machine.
When I had gone to generate the model, first I had troubles creating the connection string, something I fixed setting the SQLNET.AUTHENTICATION_SERVICES= (NONE) in the sqlnet.ora, and then, on the next step, the wizard crashes. It just briefly displays a radio button "Entity Framework 6" and then exits.
The wizard creates no issues when I generate a model from the local Oracle11g Express Database, and also I haven't needed to change the sqlnet.ora for it to work.
Should I try with different versions of ManagedDataAccess, or is this something else?
Updating ODAC to 18.3 made it work with both databases.

VS2017 doesn't see Oracle drivers?

I just recently installed VS2017 on my machine. Today I went to start a new MVC site and wanted to add a DataContext to our Oracle server. The first thing I did was go to NuGet Manager and added the Oracle Managed Drivers and then Entity Framework for Oracle and all that looked to install correctly. I then went to Add | New Item | Data | Entity Data Model | Code First from DB.
From there where it asks which database you want to connect to I only have Microsoft drivers. If I try to add a new connection, again no Oracle drivers are listed in the driver type.
I then closed the project and opened in up in VS2015. Went to add a new Data Model and it all worked as expected. Oracle drivers were available and I was able to make an Entity for my tables.
Is there something I need to install or add to my VS2017 in order to get it to see my Oracle drivers and make a connection to Oracle?
You need ODP.NET. It is in Oracle Developer Tools for Visual Studio 2017, but last version is anvalible for vs2015 https://community.oracle.com/thread/4024914

MVC 5 web application with Oracle 11g and Entity Framework without Oracle.ManagedDataAccess

my company is using the old Oracle.DataAccess and Oracle 11g (release 2) on many servers with many apps, so I can't update the driver.
Now I have to create a web app, and i'd like to use EF's code first.
The problem is that it works only with the newest ManagedDataAccess, and I can't use it.
Is there any way I can map EF with the oldest driver?
ODP.NET Managed Driver is only a single DLL (Oracle.ManagedDataAccess.dll). There is nothing to install, just put a copy of this DLL to your application directory, that's it. Thus you do not affect any other Oracle installation.

ODP .Net 12 using OraClient11

I know that the request may look somehow weird but I am trying to develop a .Net application using EF and Visual Studio 2010 against a ORACLE 10g DB.
Initially I tried with EF4 which is the embedded one in VS2010 and with ODP11 I am able to make it work. But due to some specific bugs in EF4 (StoreGeneratedPattern bug) I want to go to EF5 or EF6.
While "googleing" a bit I was able to Install EF6 using the nugets and adding the context generator for EF using the following explanation:
https://msdn.microsoft.com/en-us/data/jj206878.aspx
The problem here is that the system is not able to find a proper ODP provider for Entity Framework as I only have ODP11 installed.
Again after investigating a bit :) I saw I need ODP12 which will have full support to EF. My problem here is that all servers will be working with OraClient 11g against a Ora10g DB... I know there is no major problem (at least for the use I need) to use Ora11Client with a Ora10Server but what about ODP? I cannot change the Oracle client and I am wondering whether I can face any issue by having my application developed with ODP12 and being executed in a machine with Ora11g Client.
Is anyone having some advice on this?
Thanks a lot in advance!!
It's my understanding that the managed driver for 12 (Oracle.ManagedDataAccess and Oracle.ManagedDataAccess.EntityFramework available on NuGet) will connect to 10.2 and above and does not require ANY client installed on the computer as it contains the client it needs. It just gets installed in the app's bin directory. Be aware though that it doesn't seem to currently work with .NET 4.0 in case you're still targeting that. The 4.0 version of Oracle.ManagedDataAccess.EntityFramework shows up on NuGet as a beta version and is actually compiled against .NET 4.5.
ODP.NET 12.x has a dependency on the Oracle 12 client software so you cannot use it with the 11 client stack. You can use ODP.NET 12 to connect to databases going back to version 10.2.
You can embed the ODP.NET, unmanaged client stack in your app by using the Xcopy download, or you could use the ODP.NET, Managed Driver which is just one DLL and less than 10 MB in size.
Oracle has the concept of an "Oracle Home" (subdirectories) to allow multiple versions of software to run side by side. So that version 11 Client on your servers can exist alongside with the version 12 software you deploy there.

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