Oracle : Ошибка ORA-12315

"database link type is invalid for the ALTER DATABASE statement"
*Cause: The database link name you specified on the ALTER DATABASE
statement is not an ROM: link. You must specify an ROM: link
when using the ALTER DATABASE statement to mount or open a
secondary database.
*Action: Re-issue the ALTER DATABASE statement using a valid ROM: link to
the database you want to mount or open. If a valid ROM: link does
not exist, create one using the CREATE DATABASE LINK
command. See the Trusted ORACLE RDBMS Guide to Security Features
for more information about creating database links using
the ROM: link type.

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