Oracle : Ошибка ORA-12545

"Connect failed because target host or object does not exist"
*Cause: The address specified is not valid, or the program being
connected to does not exist.
*Action: Ensure the ADDRESS parameters have been entered correctly; the
most likely incorrect parameter is the node name. Ensure that the
executable for the server exists (perhaps "oracle" is missing.)
If the protocol is TCP/IP, edit the TNSNAMES.ORA file to change the
host name to a numeric IP address and try again.

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