J.T,

When you specify the '@' character in SQL*PLUS, you're actually compiling the package, procedure, or function. For example, if the test.sql script resides in some directory (in Windows), your command would look like this:

SQL> @C:\my_dbscripts\test
(NOTE: you don't need to put the .sql after the file name)

If the compliation is successful, it would say:
Package/Procedure/Function created.

If you need to execute the package/procedure/function you'd use the 'EXEC' statement.

Hope this helps!

- Gary