see also System.Data.OracleClient namespace discontinued?
(Firstly don’t panic yet, System.Data.OracleClient is not being removed by Microsoft yet, however it is not in the client version of .net 4)
This use to be possible by using System.Data.OracleClient, however Microsoft has decided to deprecate OracleClient. (OracleClient is the ADO.NET provider for Oracle developed by Microsoft and ships as a part of the .NET Framework.)
You could use ODP.Net, however do you wish your Sql Server customers to have to install ODP.Net? (Do you wish any of your customers to have to install Oracle software?)
DataDirect is not an option as it costs an arm and a leg; it may just about be affordable if you need to connect a single server to a mainframe. However it is not an option to expect all customers to buy it.
Moving form C# to Java is not a good option, as I am a C# programmer and wish to be able to earn a living!
Like most ISVs that have to support multiple RDBMS we only need a solution that allows us to use the small subset of Oracle that is the same as SqlServer. Therefore System.Data.OracleClient was powerful enough for us.
(Maybe we should just start storing all data in flat files, so that customer’s DBA stop trying to tell us how to write software. Oracle DBAs are the worse!)
My real question is how can I write .NET software that talks to Oracle that is us pain free to installed as .NET software that talks to SqlServer. Having to use ODP.NET just makes the oracle client install yet more painful, with yet more to go wrong.
If I was using JAVA I could just use JDBC type 4 drivers. Microsoft provides one for SqlServer and Oracle provides one for Oracle. However it seems that Oracle wishes to make .Net usage as hard as possible and Microsoft wishes to make Oracle usage as hard as possible.
So far the best option looks like devArt's dotConnect.
However I am starting to question weather .NET is a good development system for ISV, as sooner or later you always get a customer that demands oracle support. In the Java world they seem to have this problem solved.
It looks like Oracle may be about to bring out a senible Fully Managed ADO.NET provider themselfs it may even be easy to install! see here that claims Beta – 2011, Production – End of 2011.
There's a big difference between being deprecated and being removed.
If you're just using the subset of functionality that is common to both SQL Server and Oracle, then you should be fine moving through to ASP.Net 4.0 and continuing to program how you do currently.
Using something like EntitySpaces, would let you be relatively provider-agnostic. (it uses OracleClient in it's DAL)
Completely agree with Philippe about Oracle's client software being a pain. I've lost track of the number of times I've installed it and hated the experience. Give me MySQL, SQLServer or even Access in preference.
(Actually, I take back the Access comment) :-)
EDIT: The fully managed ODP.NET is now available in production. It is very small (less than 10MB) and is not dependent on other files. You can obtain it here:
http://www.oracle.com/technetwork/topics/dotnet/downloads/index.html
Original answer:
One way to easily ensure that the required Oracle client side software (including ODP.NET) is always available on the deployment machine is to embed it with your application. ODP.NET has gotten a lot easier to embed now that XCOPY ODP.NET is available. You can download it from this link:
http://www.oracle.com/technology/software/tech/windows/odpnet/index.html
With XCOPY ODP.NET, all you need to do when you deploy your application is the following:
1) Copy your application to the target machine
2) Run "install.bat" which copies a couple of Oracle DLL's to the target machine (including ODP.NET and the Oracle client side (OCI) software)
3) Run "configure.bat", which does a "gacutil" and updates the registry of the target machine
4) Provide your application with connect string information. You can use the EZCONNECT connect string ("hostname@servicename") or you (or your customer) can share preexisting sqlnet configurations by setting the TNS_ADMIN registry entry or environment variable to point to another Oracle home that has sqlnet connect aliases already configured.
That's it! It is really that simple.
I hope you will take a good look at ODP.NET XCOPY in the link above to see for yourself how easy it is these days to embed ODP.NET with your app.
Additional notes:
If you choose not to embed ODP.NET with your application, in both the case of Microsoft OracleClient and in the case of ODP.NET, there needs to be additional Oracle client side (OCI) software installed on any deployment machine. The only difference between the two cases is that when you are using ODP.NET, it also needs to exist on the deployment machine. The good news is that a typical Oracle install on your customer machine will include ODP.NET already.
Now, if your target machine already has ODP.NET installed you don't need to do anything else. You just need to distribute your application. If you do need to install ODP.NET using the standard installer, you can also download it from the link provided above. The standard ODP.NET install only takes a few minutes and configures everything for you.
And again, you can use EZConnect connect strings to make networking configuration a piece of cake, or use the TNS_ADMIN registry entry or environment variable to take advantage of pre-existing connect aliases that your customer is already used to using.
Hope this helps,
Christian Shay
Oracle
Feel free to provide your feedback on this and other future features at our feature request website: http://apex.oracle.com/pls/apex/f?p=18357:46
You might consider using SubSonic 3.0! I have it run my SQLServer, MySQL and SQLite based application and user can switch between these 3 at runtime!
Being database independent is a very hard job because there are a lot of specific things (bind variable naming, object quotation, ...). Use a library like NHibernate which puts a layer between your application and the real database.
If you have to connect to both databases, than it's a question of deployment. If you connect to oracle (using System.Data.OracleClient or Oracle.DataAccess.Client) you need oracle client software installed on your machine. The database provider deployed with framework is not enough to connect to an oracle database.
If you connect to oracle, you have to install software from oracle. If you fear the deprecation, than install and use ODP.Net. There are some differences between the 2 oracle database provider.
For better deployment oracle introduced the concept of instant client. This client can deployed using xcopy deployment. Sine oracle 11 the instant client can be bundled with ODP.Net.
The installation of ODP.Net is described in the post of Christian Shay.
The Oracle.DataAccess assembly must not be in die global assembly cache. Put it in your bin directory. The instant client used by Oracle.DataAccess must not be in a different directory on your client machine. Put it in your bin directory. The documentation describes how to configure your application to find a instant client.
I believe that ODBC can still use both SQL Server and Oracle with some transparency, so I would take a look at using ADO.Net with the ODBC provider. It won't give you all of the performance or features that SqlClient or OracleClient would, but it should be pretty close to the same code for Oracle or SQL Server.
The customer should install odp.net and the Oracle client on there machines. You should not deploy it. Your application will find the needed Oracle dll's in the GAC.