Hi All

I don't know where I am posting it at correct place or not
but I think all of you have done work on this can help me out.

I would like to know that how in a big organizations the databases are implemented. This especially I am talking about huge bans who has ATMs world wide. Also where can I get info. on these databases.
i ll also give cases which I would like to know. Is it possible just by using distributed databases or Oracle parallel server is needed for implementation

Case 1. I have a account and I am withdrawing some amount from it from U.S . and simulataneously same time my father who also has access to that account is withdrawing money from India. Now the physical datafile for this table is located in Germany; Is my transaction directly going to delete data from my table data which is stored in germany or it will change first in local replicated datafile and then change it ?

Also then if my transactions removes
all amount from my account and at next second itself my father's transaction for withdrawal takes place in ATM in India then How this integrity will be maintained ? will my fatherimmediatly get a message for no balance. (Almost at same time my and my father's transactions are requested.)

Also the above scenario is implemented using Parallel Server or Can it be implemented using just Distributed databases concepts i.e. Creating Links to remote databases and creating synonyms for tables at various locations?

I ll be glad if anyone can guide me properly on this issue?

Amol