When creating an Oracle user, you execute oracle_create_user.sql from SQL*Plus, and the following stream of errors appears. You are logged in as SYS as SYSDBA.
ORA-12154: TNS:could not resolve the connect identifier specified
Warning: You are no longer connected to ORACLE.
SP2-0640: Not connected
The Oracle Listener process was not successfully created.
This error indicates that the TNSNAMES.ora file was not created during the installation process.
Specifying the local service will create a TNSNAMES.ora file which can be used as one of the methods for resolving a connection string. While creating the protect user, the script attempts to connect to the database using TNS to resolve the connection. Without that specific information, SQL*Plus has no way to connect and generates the "SP2-0640: Not connected" error.
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