Here is a quick glance at the default locations of SPFILE and PFILE in different platforms. For instance, Linux and Windows.
Please note that, for Windows, directory name and filename are case-insensitive.
Before accessing the file, you have to know where ORACLE_HOME is in Windows.
There's no typos in the above path. The default location of PFILE on Windows truly depends on ORACLE_BASE. As you can see, they're somewhat different on path between SPFILE and PFILE on Windows.
Normally, we don't directly use PFILE to startup a RAC database, because PFILE is just a pointer to the location of SPFILE for a RAC node. Here we focus only on SPFILE below.
The location of SPFILE may be different from version to version.
How to Create Parameter Files ?
CREATE PFILE FROM SPFILE
If you create the parameter file without specifying any location, the online SPFILE used by a running instance or the default SPFILE will be used to create PFILE to its default locations.
SQL> CREATE PFILE FROM SPFILE;
Please note that, if SPFILE is not at the default location, you might get ORA-01565: error in identifying file '?=/dbs/spfile@.ora'
Or vice versa.
CREATE SPFILE FROM PFILE
SQL> CREATE SPFILE FROM PFILE;
Oracle use the default files to operate with.
How to Find SPFILE ?
Show Parameter Spfile
If you want to know the current SPFILE location, you can query the running instance.
SQL> show parameter spfile;
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
spfile string /u01/app/oracle/product/12.1.0
In some situations, DBA use a PFILE with non-conventional path to startup the database. You need more skills to find the location of PFILE.
Change Location of SPFILE
Normally, parameter files should stay where they are, but the location of SPFILE can be changed somehow, as long as you know how to do it.