The ER diagrams visualize various entities (tables) and relationships between entities. You can find them in the "Relationship" tab and the "Table references" section in each table.
To save the diagram arrangements, you need to log in with the project's owner account
Then, dbdocs will auto-save every table position whenever you (the project owner) drag-and-drop a table. Every time you & your guests visit, the arrangement in diagrams will stay still.
When you update your project,
Note: In case your DBML code doesn't contain the project name, make sure that you update the current project instead of publishing a new one by input correctly the project name.