This week a co-worker and I have been doing some rapid-fire testing to improve fast-refresh performance on an old materialized view, which does some summary aggregations on a 1.9 billion row (and growing) master table. One of the things we tested was using the new-in-11gR2 COMMIT SCN feature. There is...
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Battling Bigfile Backup Bottlenecks
Last Friday I kicked off a database backup to an NFS destination, using the standard "backup as compressed backupset database" syntax. Loyal readers of this blog may recall that I'm the proud custodian of a 25 Tb database, so this backup normally takes a few days, with an expected completion...
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Why Is My MView Log Not Purging?
A few weeks ago we saw one of our tablespaces growing at a rate much higher than the others. Taking a look we saw that the biggest users of space were two materialized view logs, one being 110 Gb and the other 60 Gb. These logs were in place to...
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What to Expect When You're Changing the DB_UNIQUE_NAME
I recently had to change the db_unique_name of a database to make it jive with our typical database/DataGuard naming policy of appending the datacenter location. For the sake of this post let's say it was changed from ORCL to ORCL_NYC, since this database is in our fictional New York City...
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Oracle Direct NFS and Infiniband: A Less-Than-Perfect Match
Readers of an earlier post on this blog will know about my latest forays into the world of Direct NFS. Part of that means stumbling over configuration hiccups or slamming into brick walls when you find new bugs.To quickly re-set the table, my organization purchased the Oracle ZFS Storage Appliance...
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