How can I make an ERD? (Mac or Win OK)

January 1, 200224 yr

Does anyone know of a good tool for creating ERD's (Entity Relationship Diagrams) for FMP db's? I would prefer it to be on Win, bit MAC is OK as long as I can have a tool to do this. Visio can do it for SQL, I believe, and Access has this feature built in.

Appreciated.

January 4, 200224 yr

Waves In Motion has a Mac-only tool called "Visualizer 1.0", which can create ER-diagrams from existing FMP databases.

I haven't tested the software myself, but judging from the screenshots (www.wmotion.com/visualizer) it looks sufficient only for small projects (maybe < 10-15 related files). I don't know how much you can "tailor" the ER "bubbles" either.

One thing that makes it so hard to write a program that create ER-diagrams from existing FMP databases is that relationships in FileMaker is not the same as relationships in Relational Database Theory (or "joins" in SQL). A FileMaker "relationsship" can be used for many other purposes than just maintaining connections and referential integrity between files. For example, self-joins for display purposes, constant relationships for data transfer, and there are many more uses for a FileMaker "relationship". So, how would the program know what is supposed to be "real" relationships, and which are not (there is no automated way of doing this).

In a traditional ER-diagram, you might use "Crow's feet" to indicate the multiplicity of a relationship (e.g. one-to-many, one-to-one, zero-to-many,...) and write other business rules that apply to them.

I've used Visio 2000 for creating ER-diagrams, and although you can get quite good results in the end, it takes a loooong time to create them, and to keep them updated, since you cannot get it to interact with FMP. If someone finds a software that is better, please let me know!

Good luck!

/Daniel

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