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Search Results for: index dates

How clustering indexes sometimes help UPDATE and DELETE performance

I recently posted a blog entry on clustering indexes, which are good for speeding up queries. Eric Day brought up the concern that clustering indexes might degrade update performance. This is often true, since any …


Tradeoffs: Updates versus Range Queries

Sorry for the delay, now on to range queries and lenient updates. Let’s call them queries and updates, for short. So far, I’ve shown that B-trees (and any of a number of other data structures) …


How Fast Can Updates Run?

Last time, I introduced the notion of strict and lenient updates. Now it’s time to see what the performance characteristics are of each. Just to rehash, we are focusing on the storage engine (a la …


Descending indexing and loose index scan

Comments to my previous posts, especially this one by Gokhan inspired me to write a bit about descending indexes and about loose index scan, or what Gokhan calls “better range” support. None of these are …


Bypassing SST in Percona XtraDB Cluster with binary logs

In my previous post, I used incremental backups in Percona XtraBackup as a method for rebuilding a Percona XtraDB Cluster (PXC) node without triggering an actual SST. Practically this reproduces the SST steps, but it …


Update on the InnoDB double-write buffer and EXT4 transactions

In a post, written a few months ago, I found that using EXT4 transactions with the “data=journal” mount option, improves the write performance significantly, by 55%, without putting data at risk. Many people commented on …


Storing time-series data with MongoDB and TokuMX

Storing time-series data is a frequent pattern for databases – be it for logs or for any kind of monitoring. Such data has the following properties: records are inserted but also never updated, the insertion …


Why Percona Acquired Tokutek: by Peter Zaitsev

It is my pleasure to announce that Percona has acquired Tokutek and will take over development and support for TokuDB® and TokuMX™ as well as the revolutionary Fractal Tree® indexing technology that enables those products …


Tokutek now part of the Percona family

It is my pleasure to announce that Percona has acquired Tokutek and will take over development and support for TokuDB® and TokuMX™ as well as the revolutionary Fractal Tree® indexing technology that enables those products …


Illustrating Primary Key models in InnoDB and their impact on disk usage

On a recent engagement I worked with a customer who makes extensive use of UUID() values for their Primary Key and stores it as char(36), and their row count on this example table has grown to …