Afternoon All,
someone might find this useful. It’s a mirror of one of my blog postings on Community.toadworld.com - https://community.toadworld.com/platforms/oracle/b/weblog/archive/2018/07/12/generate-entity-relationship-diagrams-from-a-sql-script - where you can see how to generate a diagram of the ERD around and about a single table, using a script and the graphviz utility. Handy for those occasions when you find yourself on site, with no ERD diagram and work to do!
The original posting is on my blog at http://qdosmsq.dunbar-it.co.uk/blog/2018/07/generate-entity-relationship-diagrams-from-a-sql-script/ (but only because sometimes, the miro on Toad World corrupts code listings!)