There is a flight reservation system in site1 which have SQL Server on windows server. Now i want to migrate the database in site1 to site2 which has oracle server(could on windows server, unix, sun OS). I have considered several options to solve this problem 1. establish database links in both directions 2. migrate DB at site1 to Oracle(at site1) 3. replicate DB at site1 to site2(log shipping) 4. replicate DB at site1 to site2(mirror) My question is 1. which is the most suitable option for the flight reservation system? 2. what are the tasks and procedures of the most suitable option? thanks alot!