How do I specify which Oracle client install to use?

Question

I have a server with both 10g and 11g clients installed. How do I setup the connection string to tell my ASP.NET application to use the second client which is 11g (i.e. OraClient11g_home2)?

Answer 1

From documentation:

In ODP.NET 10.2.0.2.20 and higher, ODP.NET can run more than one active Oracle Home concurrently without requiring any special setup by the administrator.

When ODP.NET is installed, the DLL search path will be based on the following order:

1. directory of the application/executable
2. directory specified by HKEY_LOCAL_MACHINE\Software\Oracle\ODP.NET\<version>\DllPath
3. directories specified by the PATH environment variable

Upon an ODP.NET installation, the DllPath registry value of type REG_SZ will be set to the %ORACLE_HOME%\bin directory where the corresponding dependent DLLs are installed.

Make sure you are using ODP.NET as a provider and set your ORACLE_HOME environment variable.

Answer 2

I fid Oracle Locator Express to be a useful tool. This will let you change your ORACLE_HOME on the fly: Oracle Locator Express