I have often used a simple query to show me DB Link info. This query still works in one of my production instances but not another:
SELECT * FROM sys.dba_db_links
The error message says table not found.
This query works in the non-functioning instance when I use Toad Datapoint (T for Data Analysts). The DBA also tested it successfully as me using SQL Plus. There must be something in the SQL Nav settings that is getting in the way. I tried starting the session with the “connect as sysdba” option, but was not authorized.