HowTo Remove parameters from the spfile

HowTo: Remove parameters from the spfile

How do you remove an SPFILE parameter (not change the value of, but actually purge it outright)?

Answer:

Use "ALTER SYSTEM RESET ..." (For database versions 9i and up)

Syntax:

ALTER SYSTEM RESET PARAMETER SID='SID|*'
ALTER SYSTEM RESET "_TRACE_FILES_PUBLIC" SCOPE=SPFILE SID='*';

NOTE: The "SID='SID|*'" argument is REQUIRED!