To associate two tables and create a parent/child relationship:
I click the “Relationship” button from the toolbar.
Select the parent table and drag to the child table.
What I notice is the existing child’s foreign key field is automatically selected (good), but in addition it also creates the foreign key column as a primary key too (wrong). So what I end up with is the child table having the proper foreign key selected AND the same field is included as the primary key (wrong). I think Toad is incorrectly creating “Primary Foreign Keys”, or I need to know how to disable this.
It sounds like you are creating an Identifying relationship which would require having both columns. If you choose Non-Identifying relationship it should function as you are expecting.
yes - Identifying relationship means RI column serves two roles: FK and part of PK. That is exactly correct and why there are two types of relationship drawing lines to choose from. Make sure to choose the right one
Thanks for the explanation. I’ll have to educate myself more on the two relationships.
Changing to a non-identifying relationship also changes the line from solid to a dash, which most in out department aren’t used to.
If you also notice that non-identifying relationship leaves the child entity a square box whereas the Identifying relationship changed the child box to rounded corner. These are the industry standards which we are following. Some people are used to non-standard styles like dashed lines meaning some portion of the cardinality (e.g. oracle style called barker notation for example). That’s not standard. TDM follows the industry standards - so for IE notation (you can swicth to IDEF1X - main menu, view, notation) that’s the norm.