Disclosure: I build Schemity , a desktop ERD tool - this post is from our blog and uses it for the examples.

TL;DR: MySQL Workbench 26, Oracle's rebuild, has no ER diagram: modeling lives on only in Workbench 8.0, which is no longer maintained. And that diagram struggles in two places: at 250 or more objects it may refuse to place them on a diagram, and it draws a relationship only where MySQL stored a foreign key, so schemas from apps that never declared their keys open with no lines. Schemity places every table it reads, infers the missing relations from column names as dashed virtual relations, and re-reads the database each time you open the diagram.

A good MySQL Workbench alternative is one that keeps the diagram correct on the schemas where Workbench's own diagram breaks down: the ones with hundreds of tables, and the ones whose foreign keys MySQL never stored.…