Net8 Variables and Windows NT
On Windows NT systems, you have two options—three, really—for setting the variables described in this chapter:
You can set these variables as environment variables from the Environment Variable tab in the System Properties dialog.
You can set these variables as environment variables from the command prompt.
You can set these variables as registry variables.
The difference between the first two options, which both involve the use of environment variables, is one of scope. When you set an environment variable from the System Properties dialog, that setting is inherited by all processes and applications that start. When you set an environment variable from a command prompt window, that setting only affects programs initiated from that particular window. It’s actually possible, for example, to have two or more Windows NT command prompt windows open, all with different values for Net8 environment variables such as LOCAL and TNS_ADMIN. That can get confusing, but occasionally it’s handy to be able to do.
Registry variables represent the third option. Registry settings are specific to an Oracle Home, so it’s possible to set different values for different Oracle Homes on your system. Registry values affect executables that are run from their corresponding Oracle Home directory.
Tip
Environment variables take precedence over registry variables.
Setting Environment Variables Under Windows NT
There are two ways to set environment variables under Windows NT. To set them ...