replication : oracle vs informix

can someone who has used both say what they liked or disliked about oracle and informix replication? i am interested in hearing from someone who has used the oracle parallel server, and if there is a comparable informix product as well... My understanding of the Oracle Parallel Server is that it shares the same drive between multiple instances. What do you see as the limitations of such an arrangement? Advantages?

Edward Rosenthal wrote: > > can someone who has used both say what they liked or disliked about > oracle and informix replication? > i am interested in hearing from someone who has used the oracle parallel > server, > and if there is a comparable informix product as well... > My understanding of the Oracle Parallel Server is that it shares the > same drive > between multiple instances. What do you see as the limitations of such > an > arrangement? Advantages? The equivalent is Informix Extended Parallel Server (XPS) which is designed to work in a clustered environment. But is works very differently. Only one co-server can access any particular disk space at any one time and if that co-server or its host should crash a replacement co-server can be started up on one of the clustered systems which have access to its disks. This is for improved uptime. The real advantage of XPS though is that you can distribute a database and even individual tables' data across multiple co-servers on separate hosts and applications will see the whole thing as a single unified database structure as if there were a single HUGE server. This permits using massive amounts of CPU, network, and disk resources that would not be possible on a single server of any kind to develop massive databases or just to distribute data to improve query performance or isolate queries of certain tables or of certain keys within a table to certain co-servers. Art S. Kagel