Re: Need help importing / exporting a schema

On 3-Jun-2007, "Ana C. Dent" <anacedent_at_hotmail.com> wrote:
>
> "Blake McBride" <blake_at_mcbride.name> wrote in
> news:1365runtsarg4b_at_news.supernews.com:
> > I don't know what CBT is and I am not looking for complete training of
> > anything.
> > I did spend a bunch of time in the docs looking for the three SIMPLE
> > things I
> > am looking for with no luck. To-date you haven't even told me how to
> > do the type of export
> > I am looking for. All other databases I've ever used take one simple
> > command to dump the
> > entire schema to a text file. I found no reference to this anywhere
> > in the docs.
> > This has got to be a simple thing. I just need to know the secret
> > command.
>
> AFAIK, there is no such "secret command".
> You should NOT extrapolate previous experience on other DBs to Oracle.
> Oracle supports many more different data type than some/many/most other
> DBs.
>
> Here is 1 simple example why "simple" data loading can get complicated.
> When a PK/FK relationship exist, the table with the PK must be loaded
> before the table with the FK can be loaded.
> Expand this to include SYNONYM, GRANT, TRIGGER & other data type it can
> be a non-trival operation.
>

The dump would contain all the create table commands first, then the primary keys, indexes, foreign keys, etc. Done in this order there is no problem with dependencies. Also, if a database only contains string and numeric columns then exporting and importing in text based SQL commands works fine. The main reason I can see why Oracle won't provide text SQL schemas is to make it maximally difficult to change databases.

Without a schema dump I can't keep an Oracle schema in sync with a postgres schema. I have my own program to do this (works with MSSQL & Postgres) but depends on a textual SQL schema file. This presents a significant problem for me.

Blake McBride Received on Sun Jun 03 2007 - 12:23:51 CDT