Tag: multiplex

Backup, Replicate& Multiplex – Redundancy Helps

Flashback! Its November 2007; I am just about three(3) months into my new Job as a DBA; and one of the few things I am tasked to do is babysit an OLTP system with 256GB RAM, a 15TB sized Oracle database and 32 multicore processors –an HP Proliant, a beast, nothing quite like anything I have ever worked with. The system basically maintained the Prepaid subscriber lifecycle process –dynamically computing daily subscriber additions and churn figures by making use of RGE events. So thirty(30) minutes after arriving at the office, I accidentally truncated the table that stored historical details of all churned subscribers, from as far back as 1998 (9 years worth of data). We had a very rudimentary backup mechanism at the time –daily Oracle exports of “critical” aggregated tables. I spent the whole day trying to figure out what to do and I never told anyone what I had done 😉 The good thing is I managed to restore the previous day’s hot backup and then performed a very primitive roll-forward of all transactions for that day. (more…)