Where does the database link SYS_HUB come from?

This blog lives a lot from customer’s feedback and updates. And these days, Nicolas Jardot from dbi-services in Switzerland sent me an email asking: Where does the database link SYS_HUB come from? And if he can delete it or if it has any deeper purpose. Neither Google nor MOS reveal a lot of useful information Where does the database link SYS_HUB come from? I took my vanilla 18.3.0 database in our hands-on lab and check: column owner format a5 column db_link format a12 column username format a12 column host format a12 select con_id, owner, db_link, username, host from cdb_db_links; CON_ID…