Question : What is the best way to migrate from Sybase 12.5 to Sybase 15

What approach will be the best to migrate database from Sybase 12.5 to Sybase 15.0? The database is 12.5 version is quite large.

Thanks.

Answer : What is the best way to migrate from Sybase 12.5 to Sybase 15

The best way is to do as Joe suggested but I would add that, if at all possible, find enough disk space to keep both databases around.  Doing a one-time all-or-nothing migration is not a good idea for a bunch of reasons.

As far as things you will run into when migrating from 12.5.x to 15.x, there are not many but you still need to be aware of them.
 - query optimization has changed.  You may have to actually remove some forceplan statements and hints in order to get the best out of v15
 - the old assumption that a group by would do an implied order by on the same columns is not longer valid so you may have to add order bys in a few places
 - if you use cursors and update the underlying table(s) of the cursor, you can get some weird results.  You will need to add the "insensitive" clause to the cursors in those cases.
 - you can no longer count on tables with cluster indexes having absolute physical order, particularly temp tables
 - there have been some minor changes to system tables that probably don't affect you however, if you have written system routines that look at datatypes of columns or sp arguments or look at the sysprocesses table, you might have to make some changes.

That's about all I can think of right now.  Joe, do you have any other 12.5 to 15 gotchas to add?

Regards,
Bill