Re: Oracle Replication (Multi master or Snapshot)

Replication WILL affect the performance of your production database, and can be a real swine to set up and look after.

Depending on the kind of ad-hoc querying you want to do, and which version or product you have, I'd be tempted to use Oracle's hot-standy, especially if you can tolerate a 10 minute lag.

The standby database accepts the archived redo-logs from the production database and with Enterprise Edition, it's allowed to be opened in read-only mode. There's always a lag between the primary and standby which you can influence by tweaking the size of the redo log.

The downside is you'll have to switch between constant recovery mode and open mode prior to querying, then back again, but it's doable, and won't degrade the performance of your production site.

In message <f489430.0301170743.2b71e081_at_posting.google.com>, Michael Kelly <wakeboard_at_mindspring.com> writes
>We are looking at setting up Oracle replication to replicate our
>financial system database to another server (connected via switched
>100 MB ethernet) at the same location so that we can perform ad-hoc
>reporting against the replicated database and not affect performance
>of the OLTP financial system.
>
>We have a requirement that the data be replicated near real time.
>Because the replicated database will only be used for reporting then
>it only need to be read-only.
>
>My question is, based on the requirement of near real time replicated
>data and the read only use of the replicated database, should we go
>with the multi-master setup (for near real time data replication) or
>with the read-only snapshot? My preference is to go with a read-only
>snapshot but not sure if that setup will support near real time
>replication. What is a reasonable short timeframe for snapshot
>refresh (every 5 minutes, 10 minutes, 15 minutes, etc)?
>
>Thanks in advance for your comments/suggestions.

-- 
mark chadwick