Re: switch sybase to oracle

Paul:

    I am an Oracle DBA. I would like to share my expertize in Oracle DBA area.
When You want migrate database from Sybase from Oracle, the following things need to be planed ahead

1. Do you plan to use RAID device and how to you use it? If you utilize the adventage of RAID (stripe and mirror), Striping is for performance and mirror is for safety, then you can put all the tablespaces in to one large logical file system without worrying about the mappin from tablespaces to hard disk devices.
2. Backup existing Sybase databases. jsut in case of the failure of the database migration, You can go back to Sybase databases without interrupting your database services.
3. Make all the modifications (Triggers, database schema....)
4. Testing migration on other environments to ensure the quality of migration.
5. Migrate to Oracle database
6. Test all the applications

To answer 2 of the question in your email 1.Oracle provides 12 kind of triggers (insert,delete,update,before or after commit, every row or once for a table). For details, please check Oracle reference book. Oracle has similar functionality as Sybase does.

2. You can create tables on different tablespaces. One table can only belong to one table spaces in general ( Oracle 7.3.3). If you use partition view feature in Oracle 8, one table can be partitioned into multiple tablespaces( this is for huge table only).

Good Luck

Paul Chang wrote in message <6tbvdi$2l5$1_at_ebaynews1.Ebay.Sun.COM>...
>
>In our current sybase system, we have 4 to 5 databases.
>All objects are owned by sa.
>some tables have relationship resided in different db.
>Thus we have triggers doing RI checking cross db.
>
>Once we migration to Oracle, we need to resign the physical structure?
>
>I mean each db in sybase correcponds to one tablespace in Oracle?
>
>Does Oracle allow different table in different tablespace having
>relationship? Can trigger do RI checking across tablespace?
>
>thanks,
>
>Paul.
>
Received on Sun Sep 13 1998 - 21:23:33 CEST