Identify Instance name

Query To Check on which oracle instance you are working
      select * from global_name;
   scriptoutput -
              GLOBAL_NAME
               ------------
                  LSENBCNV                      (Name of the oracle instance)

Or use below query

SELECT    SYS_CONTEXT ('USERENV', 'CURRENT_USER')
       || '@'
       || SYS_CONTEXT ('USERENV', 'DB_NAME') AS DATABASE
  FROM DUAL;

scriptoutput -- CNVAR1@LSENBCNV