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Free database modelling tools?

Im in search for a preferrably free data modelling tool that can create a DB model from reading a DB schema.

I need this to do nice ER-diagrams of a MySQL DB. Is there such a tool or am I looking at creating my own for this one?

If you guys knows such a tool, please let me know. It doesnt have to be free.


Wednesday, February 5, 2003

Microsoft should still have VisualModeler 3.1 available for download which will do all that and more.

You might have to search hard for the download though.

Simon Lucy
Wednesday, February 5, 2003

Wednesday, February 5, 2003

there are a number of tools that could fit your bill.

Case studio -
Win Design -

are two that immediately spring to mind.

Wednesday, February 5, 2003

If this is just a one-time deal, you might as well go with a trial version of one of the main modeling tools.

I've used Embarcadero's ER/Studio 15-day trial for my one-time diagram printing needs.

ERwin is another popular tool with an evaluation version available for download:

If you find you like Object Role Modeling from the free VisioModeler mentioned above, you may eventually want to get Visio for Enterprise Architects, which contains the latest and greatest version of the same ORM tool.  Unfortunately it can only be acquired by purchasing Visual Studio .NET Enterprise Architect, the most expensive version.

Wednesday, February 5, 2003

I just started using this tool. Quite nice so far and it has direct support for MySQL.

Wednesday, February 5, 2003

I've used ER/Win, ERStudio, TOAD, and Visio for database modeling.

I've found Dezign for Databases to be every bit as useful as any of the enterprise tools for db modeling, and it's only $150:


Philip Janus
Wednesday, February 5, 2003

Sybase powerdesigner gives you a 45-day evalaution

Powerdesigner gives you
business process modelling (light stuff like ebxml)
OO modeling (full UML, J2ee, .Net, Tomcat, Websphere...)
Conceptual modelling (pure erd)
physical modlling( all the major and minor rdbms)
free model (roll your own)

with intra model generation (eg oom to oom) and
inter model generation(eg oom to pdm - O-R mappings)
a generation template language and scriptable meta model

oh yeas and report gen facility (rtf html)
and enterprise repository to optionally hold all of this

I am a bit biassed but i would like it if Joel would pass an opinion next to erwin and embarcadero.

Remember with pd one tool - no together, no rational, no visio, no bridges (erwin, erstudio to describe)

Wednesday, February 5, 2003

Thanks alot guys. I will check all programs out.

Wednesday, February 5, 2003

If you look at the two pages of mine:

The first ER diagram was done with Viso, and is actually the first design doc I use for many of my table designs (only tables fields yet!…that is how my brain works!).

This  2nd ER diagram was done with ms-access using the above one as a design starting point. That is:

Note how some 1 to many relationships show a little “arrow” and some don’t. The difference is that ones with a arrow don’t require a child reocrd.
(thus some tables thus don’t require a child record, and some do. Those are in fact default left joins).

What I like about the ms-access editor is that you can also enforce the relationships. (and you can also jump to the table design from the ER window directly).

MySql  VERY recently got some enforceable RI at the table/engine level. This means I am now awaiting that killer ER editor for MySql, since a ER diagram is not much of a design tool unless it lets you put back the RI changes to the database! You need to be able to sync small changes in the ER diagram to the actuall production database (and that should include RI stuff).

Without that feature, you are back down to using DDL statements to setup the referential integrity (RI).

Albert D. Kallal
Edmonton, Alberta Canada

Albert D. Kallal
Wednesday, February 5, 2003

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