By default, pgAdmin creates ERD for all the related tables. To generate ERD for a single table, you can set the value at Preferences -> ERD tool -> Options -> Table Relation Depth to 0.
I have a large and very complicated database, where the complete ERD is so large that it is very hard to find anything (even with a 45" monitor and zooming out). Hundreds of tables, hundreds or relationships.
I have tried to create an ERD for a single table only, but that does not seem to work - every time I do it, the result is a complete ERD for the whole database.
Is this a bug, or have I missed something? I'm selecting one table, right-click and select "ERD for Table". But I get the complete diagram...