visualize database schema

[juliane26]

I have a new database to handle. The schema is generated by a (java) persistence layer with no constraints implemented. constraints are checked by the persisitence layer within the application.
In a way you could say in this project database design does (almost) not exist. Please don't blame me - no way to change that

Now I am looking for a way to visualze the schema anyway to get kind of a control. I was thinking about doing the following:

- implement informational constraints. Nobody can blame me then for doublechecking constraints. And the persistence layer can be told to generate them.

- Use a tool to visualize the schema with those informational constraints.

questions:
1) do you guys think that is actually possible ?

2) which tools to use for this re-engineering ? I think my boss won't buy me a rational licence. I have no Erwin either, any suggestions are welcome.
I want to pump in the schema-DDL and get the modell as a nice graph.

3) I have heard db2look can generate the schema using the TeX option, but I did not get it working on windows and could not test. Did anybody actually try it ?

Oh well, any help is appreciated.

It is just tough to go first through the object-modell layer and see which classes are related when checking for missing indexes and doing any kind of performance tuning. Also to check that the persistence modell actually makes sense (checking 1..1 relations etc.) is rather difficult since nothing is automated for me from the modeller side ...

 

[aixnag]

Suggest you to Download and use free tool called
'Quest Central for DB2' for all your needs.


hope it helps.


aixnag
IBM Certified Specialist - P-series AIX 5L Administration
IBM Certified Specialist - AIX V4 HACMP
IBM eServer Certified Specialist – p690 Technical Support
IBM Certified Solutions Expert - DB2 UDB V7.1 Database Administration for Unix, Linux, Windows and OS/2

 

[juliane26]

Quest Central is not free at all, even for the trial you have to contact quest sales to get a licence key ....

Juliane

 

[rbod]

If your need is urgent and if the schema does not change very frequently, you can use db2look to generate the ddl and then download a trial version of Erwin or Embarcadero and do a reverse engineering to generate the visual model.

Ofcourse, the trial versions have limitations.

 

[juliane26]

well, I am going to try the MS Visio now, since we have it around, probably followed by Erwin.
Can Embarcadero do reverse engineering as well? Good to know, I never used it. Do you know whether that is included in the DBArtisan or do I need something additional like ERStudio ?

If I can proof it something actually working I hope to get a licence.


Juliane

 

[rbod]

Erwin/ERStudio can do reverse engineering.
DBArtisan is more of an administration tool.

So, how are you going to create the model in Visio?manually?

 

[juliane26]

Visio can do reverse engineering for databases. You need to register for ODBC - and thats it. Works fine for my purpose, solved my problem to have a look.

Of course you cannot change the model and then apply your changes to the database. But I don't need that, so it's ok.


Juliane

 

[juliane26]

Just in case somebody searching here, MS Visio finally failed - it could not scale for 1400 tables. I let it run overnight and then killed it.
It has a somewhat funny architecture, probably interesting to ODBC trace it. Kept the database a little busy as well all the time.

The Embarcadero ER Studion does a good job with 5-10 min time on an older laptop with 500MB memory for 1400 tables re-engineering including references from a DB2 database.
Another advantage: different view options let you choose what is good for your model (hierarchical, symmetric, rectangular ...)

Juliane