Winan,

>Hi James, Thanks for prompt reply!
>
>Q:Do you need real time replication or periodic?
>A:Yes, I need real time replication
>

Just to clarify, if a user changes or adds a row in branch A then you will need to see the changes at Home Office in a few seconds. If this is the case then ASA will not work for you. ASA is designed to do periodic replication. I have a location that is doing this every 10 minutes and it has caused some update contention.

>Q:Do you need to replicate from head office to Branch A or B…?
>A:No, what I need is to replicate DB from branches (A,B,C,D,E) to Head Office.

>Q:Do you need to replicate from Branch A to B or C…?
>A:Yes, I need is to replicate DB from branches (A,B,C,D,E) to Head Office.

If you need to do this then you will have to be able to replicate from HO to Branch offices. Otherwise, how would you get data from A to B.

>
>Q:Is it possible that a user at head office will change a row that also will be changed at one of the branches?
>A:Yes

You will need to design conflict resolution into the system. If user at B changes a row and then user at HO changes the same record then who is correct? This can be one of the more complex issues to solve.

>
>Do you need to have any of the data partitioned? For example, some data from A will go to C but not B,D, or E?
>A: No.
>
>FYI, I had 4 choices whether I use Sybase ASA 7 (Sorry, I dont have new version) or SQL Server or Oracle 10g Express version or MySQL 5..

I would not ASA 7 becase of too many bugs. ASA 9 is much better and there is a way to push updates to all the remote databases.

>
>Do you have any idea? and can you suggest me what DB system should I use to accomodate the above requirements? ..

I have had some experience with MS SQL and it was a problem with two way replication. That was a couple of versions back so it might be better now. MS would replicate very quickly so it would be a better solution for real time replication. I have not used mySql or Oracle so I can't help you there. Sybase has a stand alone product (I can't remeber the name) that will work with many different databases but it is very expensive.

The best advice that I can give you is to make sure you have a very good understanding of what data needs to mover where and how often before impementaion. It is very difficult to make schema changes and design changes on a working system.

>
>Your prompt reply would be appreciated!..
>
>Thanks a lot in advance
>
>Regards,
>Winanjaya