Need affordable ERD database modeling software that will reverse engineer large Postgresql 7.3 database

Posted on 2008-10-26
Medium Priority
Last Modified: 2012-06-21
I have a large Postgresql 7.3 database on a Linux RHEL3 server, and I need to quickly make a very detailed ER diagram to use in a grant proposal for rewriting our (small college) system (ERW framework and PHP) into Ruby on Rails.

The developer recommended ERwin, but it is over 1,000 dollars per license, so that is out.

I tried MicroOLAP Database Designer for Postgresql, and it seems really promising. I didn't have to jump through any hoops or install anything in order to connect it to my db, and it reverse engineered the whole thing. However, when I tried to save, it crashed. I tried for four days, sending error reports to MicroOLAP, and even exchanged email with the president of the company. I would be very happy with this software, but I can't use it if I can't save the file.

I tried Toad Data Modeler, but version 3 only works for Postgresql 8.x, and I need to reverse engineer 7.3. The previous product, Case Studio 2, reportedly works with 7.3, but even though I was able to download it, there is no trial key, so I can't test it out.

I tried ConceptDraw, also. It supposedly can reverse engineer databases through ODBC, and I went through the trouble of setting up ODBC in order to test it. However, I can't find the reverse engineer command or menu or dialog. There was a community forum on the company's website, where the company moderator gave a short howto on reverse engineering, but the template she refers to is not in software. I replied to her, and so did another user, and she never got back to us. The other user's reply was sent over a year ago, so I don't think ConceptDraw is going to work.

I am under a tight deadline for getting this estimate, and I need this ER diagram to do so, so I would really appreciate any advice any of you have.
Question by:shinmaikeru
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 6
  • 2
  • 2

Expert Comment

ID: 22810305
You could try ERCreator.  A tenth the price of ERWin, with a free demo (doesn't let you save, but you can try creating the graph before you plunk down your $99.)

Assisted Solution

slinkygn earned 300 total points
ID: 22810306
Goodness, I'm sorry.  Left out the link.


Accepted Solution

thewild earned 1200 total points
ID: 22810526
We have tested many of these products ourselves and ended up using Entreprise Architect 7.1
I think a single lincense is a bit aboce 300$.

It can natively reverse enginer PostgreSQL dbs, and has all the diagram functionalities you want (and more, I think it is a full UML2.0 modeler).
Windows Server 2016: All you need to know

Learn about Hyper-V features that increase functionality and usability of Microsoft Windows Server 2016. Also, throughout this eBook, you’ll find some basic PowerShell examples that will help you leverage the scripts in your environments!


Author Comment

ID: 22811896
Testing them out now. I am also testing out Happy Fish, which works really well, too. I think I might have found the reason that MicroOLAP was crashing, but I won't know until tomorrow.

Enterprise Architect is an amazing software, especially for that price. I think it looks really promising, but I might have to use one of the others, simply because I don't know UML that well. I know Chen diagrams and relational database theory inside and out, and what's more, I like that stuff. I can see that diagramming the db as a set of class diagrams would be better, but EA's reverse engineering does not seem able to import the relationships between the tables. It did a great job of importing 130 tables as classes, but there are no relationships there, so I would have to do all of them manually, and I don't have the leisure of doing that or of teaching myself UML right now. I will come back to EA when I am in a better situation.

I need to spend a little more time comparing modelcreator, MicroOLAP, and Happy Fish.

Author Closing Comment

ID: 31512940
Both ERCreator and Enterprise Architect are good, but ERCreator links between tables are, like those of Happy Fish, only perpendicular lines, which in a large diagram tend to overlap, making the diagram hard to read. EA is fantastic sofware for the price, and the reverse engineering is amazing... however, it does not do conventional Chen or crow's feet diagrams. EA only does a flavor of the not-yet-decided UML data modeling diagrams, and to be honest, if you don't yet know UML and use UML tools, the learning curve is more like a brick wall. Because I am already over deadline, I will be looking for a Chen ER tool because I already know that stuff pretty well, but once I get over this hump, I want to learn UML using EA. It's great.

As for modeling, I found http://www.modelright.com/. It has a community edition and a free read-only lite edition so that the models you create can be viewed by others without the need for them to buy the software. There is a very active member's forum and responsive support, and the reverse engineering is really good. Their support (and the support from MicroOLAP) clued me in to why I was not able to get reverse engineering working: Postgresql 7.3 is not well-supported by ODBC, and it has problems with even postgres-specific links, like those used by MicroOLAP). ModelRight will soon release a postgresql-specific version that does not use ODBC, so it will be even better than it is. Another big plus for me is the fact that it allows you to switch between perpendicular and curved lines to represent relationships. Highly recommended.

Expert Comment

ID: 22874113
Hello MichealECooper,
Thanks for the commenting extensively on this, it is always nice to have as many advices as possible about modeling softwares.

I will give a look at ModelRight, it it looks good and I like the graphs at first glance.
Quite expensive though, but maybe it is worth the price.


Author Comment

ID: 22882151
For straight ER diagrams, it seems really good, but I think that, if you can handle the UML (which I cannot yet), the Enterprise Architect that you suggested is a better buy. You can model the entire application, it seems. I would really like to be able to plan my entire app in EA. Hopefully, I will get there soon.

Author Comment

ID: 22937635
Additional info on the choice of ERD tools:

Support from ModelRight and MicroOLAP both told me that their software was not fully compatible with Postgresql 7.3, so I installed 8.3 in a windows VM and imported my data structure. Well, ModelRight did not reverse engineer ANY of the references, but MicroOLAP and EnterpriseArchitect did. HappyFish is really easy to use, but the relationships are diagrammed as straight lines that bend at right angles, and it is really hard to read. EA has readable links, but you have to manually adjust some of them, and there are these pin points that are fixed to the background so that it can sometimes be really hard to get things organized.

MicroOLAP looks great and works really fast. It is light and comfy software. However, it does not have explicit cardinality settings in the relationship properties, so it is kind of indirect in the way it defines a 1-1 relationship versus a Many-1 or 0-1.

EA has a lot of settings and offers a lot of info to associate with your tables. I have been reading the website's articles on the UML Data Modeling Profile that EA supports. I have decided to try to use EA instead of the other options because of the idea that UML as a unified system can model the entire application, including code, network, and database. This idea really appeals to me. For reference, see
and then look at EA's primer on the Data Model Profile at

EA has two big problems:
1 - It is not as easy to read and see on screen as other tools.
2 - It is slow. I can only assume that this is because it is a big Java program, but it is really slow when compared with MicroOLAP.

So I am going with EA, in spite of the jerky motion when in use and the slow response, because I hope to move from Data Modeling into using EA to model my programs, as well.

Author Comment

ID: 22937646
One more link on the UML Data Modeling Profile:

Author Comment

ID: 22946102
Wrote this up in blog as a more detailed review of ERD tools and a discussion of the UML Data Modeling Profile:

Featured Post

Will your db performance match your db growth?

In Percona’s white paper “Performance at Scale: Keeping Your Database on Its Toes,” we take a high-level approach to what you need to think about when planning for database scalability.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Best database to use for Maps is PostgreSQL. This is an open source database. Comes as a package with most Linux OS. For more info visit the following site: http://www.postgresql.org/ (http://www.postgresql.org/) This requires some add-o…
I'd like to talk about something that is near and dear to my heart: build systems. Without them, building software is all about compiling locally, with software versions everywhere. It can be a mess. Today we are going to discuss building a small di…
This tutorial will introduce the viewer to VisualVM for the Java platform application. This video explains an example program and covers the Overview, Monitor, and Heap Dump tabs.
This tutorial explains how to use the VisualVM tool for the Java platform application. This video goes into detail on the Threads, Sampler, and Profiler tabs.
Suggested Courses

770 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question