Re: Looking for a db schema read/write/synch tool

I also use Sybase PowerDesigner. I only use to translate schema from one database to another. I don't use it to do differences, or to write migration scripts. I write my own migration scripts.

Even for translating one database to another, you have to be smart about picking your starting point. For instance, I write my overall physical model using the Oracle physical model. I do that not because Oracle is a good database. I do that because Oracle is the lowest common denominator--the worst database. Oracle has the least amount of basic design features and requires physical parameters that only Oracle needs (because of Oracle's lack of doing things right in the first place.) When I use PowerDesigner to translate the model to Sybase, MS SQL Server or Postgres, it drops all the dross required by Oracle. If I started with the Sybase model, there is no room for the dross required by Oracle. PowerDesigner cannot add dross; but it can drop dross.

I also had to change PowerDesigner's XML datatype definition files for Oracle--so that PowerDesigner will translate Oracle's number(10) to int, number(5) to smallint, number(2) to tinyint.. Otherwise, you get numeric(10), numeric(5), and number(2) You don't want numeric as a rule because it is not the native IEEE integer datatype of the computer. IEEE good. Oracle only supports the "number" datatype for numbers. "number" is not IEEE. This is bad, a birth defect akin to a club foot. A big performance hit. And in Oracle, there is no remedy for it. You have to live with it.

Also remember, tools like PowerDesigner only translate table, index and view definitions. They don't handle translating stored procedures. As far as I know, nothing can do that. And I do not see how a product could possibly do that.

Brian Ceccarelli
Talus Software
http://www.talussoftware.com

"Daniel Morgan" <damorgan_at_x.washington.edu> wrote in message news:1084503930.7535_at_yasure...
> Chad Smith wrote:
>
> > Hello,
> >
> > I'm relatively new to the database world so please forgive me in
> > advance for my ignorance. I have recently been tasked at my job with
> > finding a tool that will perform the following tasks: 1) extract
> > schemas from a db, 2) produce a difference report between schemas from
> > two databases, and 3) synchronize two schemas. The purpose is for
> > product upgrades during which an existing database schema will need to
> > be synchronized with a baseline schema.
> >
> > The tool must support the following database vendors (versions given
> > in parenthesis): Oracle (8i/9i), Sybase (12.x), Informix (9.x), MSS
> > 2000, and IBM DB2 (7/8).
Received on Thu May 20 2004 - 03:54:07 CEST