Oracle : Ошибка ORA-12505

"TNS:listener does not currently know of SID given in connect descriptor"
*Cause: The listener received a request to establish a connection to a
database or other service. The connect descriptor received by the listener
specified a SID for an instance (usually a database instance) that either
has not yet dynamically registered with the listener or has not been
statically configured for the listener. This may be a temporary condition
such as after the listener has started, but before the database instance
has registered with the listener.
- Wait a moment and try to connect a second time.
- Check which instances are currently known by the listener by executing:
lsnrctl services
- Check that the SID parameter in the connect descriptor specifies
an instance known by the listener.
- Check for an event in the listener.log file.

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