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Search Results for: range index

Strange Loop Talk on Indexing

At next week’s Strange Loop conference, I will give a talk on “Understanding Indexing”. The session is 10 am Monday, September 24th, and will be held in the Midland States Room.

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Why InnoDB index cardinality varies strangely

This is a very old draft, from early 2007 in fact. At that time I started to look into something interesting with the index cardinality statistics reported by InnoDB tables. The cardinality varies because it’s …

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MySQL indexing 101: a challenging single-table query

We discussed in an earlier post how to design indexes for many types of queries using a single table. Here is a real-world example of the challenges you will face when trying to optimize queries: …

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InnoDB locks and deadlocks with or without index for different isolation level

Recently, I was working on one of the issue related to locks and deadlocks with InnoDB tables and I found very interesting details about how InnoDB locks and deadlocks works with or without index for different Isolation levels. …

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Multiple column index vs multiple indexes with MySQL 5.6

A question often comes when talking about indexing: should we use multiple column indexes or multiple indexes on single columns? Peter Zaitsev wrote about it back in 2008 and the conclusion then was that a multiple …

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Introducing TokuMX Clustering Indexes for MongoDB

Since introducing TokuMX, we’ve discussed benefits that TokuMX has for existing MongoDB applications that require no changes. In this post, I introduce an extension we’ve made to the indexing API: clustering indexes, a tool that …

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Lock Diagnostics and Index Usage Statistics in TokuMX v1.2.1

TokuMX v1.2.1 introduces two simple new features to help you understand the performance characteristics of your database: lock diagnostics and index usage statistics. We’d like to take you through a few examples of what these …

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Why Unique Indexes are Bad

Before creating a unique index in TokuMX or TokuDB, ask yourself, “does my application really depend on the database enforcing uniqueness of this key?” If the answer is ANYTHING other than yes, do not declare …

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MongoDB Index Shootout: Covered Indexes vs. Clustered Fractal Tree Indexes

In my two previous blogs I wrote about our implementation of Fractal Tree Indexes on MongoDB, showing a 10x insertion performance increase and a 268x query performance increase. MongoDB’s covered indexes can provide some performance …

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268x Query Performance Increase for MongoDB with Fractal Tree Indexes, SAY WHAT?

Last week I wrote about our 10x insertion performance increase with MongoDB. We’ve continued our experimental integration of Fractal Tree® Indexes into MongoDB, adding support for clustered indexes.  A clustered index stores all non-index fields …

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