Re: switch sybase to oracle

On 21 Aug 1998 21:04:04 GMT, Paul Chang <pch_at_pinnacle.EBay.Sun.COM> wrote:
>Hi,
>
>We have an existing application using sybase as backend and we might need
>to use oracle instead.
>We use same ER-Diagram as used for sybase from ERWin tool.
>
>In sybase we can have multiple databases based on the physical db design.
>How about in Oracle?

You might consider multiple schemas instead.

>I am thinging creating one instance (database) containing many tablespaces.
>Each tablespace represents one entity.

That is one way to do it, which makes sense because tablespaces can be backed up separately.

>
>How to estimate the tablespace size ? based on how many tables reside in
>that tablespace?

Based on how big the rows are times how many of them plus some overhead. See the Oracle Concepts Manual and get one of the Oracle Admin books.

>
>Can anybody share the experience about logical/physical db design
>if converting sybase to oracle?

Whenever I've done this, I've found a reasonably relational design moves right over. Too much denormalization makes a hassle.

>What need to be considered?

It's the stored procedures that really work differently.

>
>thanks,
>
>Paul.
>

comp.databases.oracle is supposedly obsolete. See http://ourworld.compuserve.com/homepages/joel_garry/oraclech.htm for the real groups.

>
>
>
>
>

-- 
These opinions are my own and not necessarily those of Information Quest or 
Pebble In The Sky http://www.informationquest.com mailto:jgarry_at_nospameiq.com
http://ourworld.compuserve.com/homepages/joel_garry   Remove nospam to reply.  
mailto:joel_garry_at_compuserve.nospam.com  "See your DBA?"  I AM the @#%*& DBA!