Oracle Indexes

I’ll be presenting a new round of “Let’s Talk Database” events around Australia and NZ next month. These are free events but have often “sold out” in the past so booking early is recommended to avoid disappointment. All events run between 9:00am – 12:30pm and are followed by a networking lunch. Currently, the confirmed events are: Sydney – Tuesday, […]

It’s been a very tough week so to help keep my mind off rather sad events, thought I’ll finish off one of my unpublished articles. Initrans is a physical attribute that determines the initial number of concurrent transaction entries allocated within each data block for a given table/index/cluster. Every transaction that updates a block has to acquire an […]

In mid-April 1979, as a nerdy 13 year old, I sat in my bedroom in Sale, North England listening to the radio when a song called “Boys Keep Swinging” came on by an singer called David Bowie who I never heard of before. I instantly loved it and taped it next time it came on the radio via my […]

This come up recently with a customer and I saw a related question on OTN that made me realize I haven’t previously discussed the SKIP_UNUSABLE_INDEXES parameter. Let me start by making a very simple point. All it potentially takes to make your entire database effectively inoperable or indeed to maybe bring down a RAC instance is […]

I’ll be doing the rounds in Australia/NZ in the coming weeks so plenty of opportunity to catch-up and see me in action

I previously discussed how Index Advanced Compression can automatically determine not only the correct number of columns to compress, but also the correct number of columns to compress within specific leaf blocks of the index. However, this doesn’t mean we can just order the columns within the index without due consideration from a “compression” perspective. As […]

I’ve discussed Index Advanced Compression here a number of times previously. It’s the really cool additional capability introduced to the Advanced Compression Option with 12.1.0.2, that not only makes compressing indexes a much easier exercise but also enables indexes to be compressed more effectively than previously possible. Thought I might look at a multi-column index to highlight just […]

I’ve just accepted an invitation to present the Hotsos Symposium Training Day on 10 March 2016 in sunny Dallas, Texas. In the age of Exadata and In-Memory databases, it’ll be an updated and consolidated version of my Index Internals and Best Practices seminar. With an emphasis on using indexes appropriately to boost performance, it’ll feature […]

For those of you lucky enough to live on the western half of Australia, I’ll be presenting at a couple of events in both Perth and Adelaide in the coming weeks. On Wednesday, 9th September 2015, I’ll be presenting on Oracle Database 12c New Features For DBAs (and Developers) at a “Let’s Talk Oracle” event […]

A recent question on the OTN Forums Reg: Index – Gathering Statistics vs. Rebuild got me thinking on a scenario not unlike the one raised in the question where a newly populated index might immediately benefit from a coalesce. I’ve previously discussed some of the pertinent concepts such as how index rebuilds can make indexes bigger, not smaller […]