In the shutdown status, the database only has the PLSExtProc service and is in an unknown state.
The database is in the nomount status and has SID, SIDXDB, SID_XPT, and PLSExtProc services. The SID, SIDXDB, and SID_XPT services are in the ready/ready status, and the PLSExtProc is unknown.
The following describes the functions of each service:
SID: start the service of the database instance
SIDXDB: a service that efficiently processes XML data. port 8080 is used by default.
SID_XPT: The Service prepared for the DG, which is used by the db broker. You can delete it if you do not need the DG.
PLSExtProc: PL/SQL services that call external interfaces (processes written in C and JAVA)-vulnerable to attacks
How to stop starting the PLSExtProc service when listening is started: Remove this option from listerner. ora directly.
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