Application and Database migration to Oracle

I am looking for approaches, case study and other information that can be helpful and be utilized in planning and execution of migration of application and database from Sybase to Oracle.

The applications are divided into two categories for now, 1.OLTP applications with business logic divided into database and application layer.
2. Non OLTP applications with database being used for reporting only.

If you have performed any such migration and have blogged about your experiences, read some articles, suggested tools or any information that you feel would be helpful.

Please share the URL / articles or other form in which the information is available, you can send me a direct mail .

I am reaching to you all as I am sure in the list many would have faced / involved in such projects.

Thanking you all for your help and time on this.

Regards,
Vijay Sehgal.

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