Re: Oracle replication wasRe: Sybase 11 TPCC on DEC (your comments please)
Posted in 1996
>While with the two-phased commit strategy you can be sure that all >replicate databases are consistent at any given time with the primary, >performance does suffer and the possibility of transaction rollback at >all sites increases with each replicate database entered into the >system - if one replicate database is unavailable, the transaction >fails at all sites. Sorry, that is incorrect. Symmetric replication maintains queues for each site involved and replicates to each queue independantly. I.e if a change must be replicated to 2 sites then that produces 2 queued entries. Each one is dealt with separately - the availability of one machine will not prevent a change at another. I am assuming you are comparing like with like here - replication server vs symmetric replication and not replication server vs Oracle7 + Distributed Option. Dave