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Optimizing slow web pages with mk-query-digest

I don’t use many tools in my consulting practice but for the ones I do, I try to know them as best as I can. I’ve been using mk-query-digest for almost as long as it …

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Finding what Created_tmp_disk_tables with log_slow_filter

Whilst working with a client recently I noticed a large number of temporary tables being created on disk.

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Working with large data sets in MySQL

What does working with large data sets in mySQL teach you ? Of course you have to learn a lot about query optimization, art of building summary tables and tricks of executing queries exactly as …

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Is it query which needs to be optimized ?

Last few days I had a lot of a lot of questions at MySQL Performance Forum as well as from our customers regarding query optimization… which had one thing in common – It is not …

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Why MySQL could be slow with large tables ?

If you’ve been reading enough database related forums, mailing lists or blogs you probably heard complains about MySQL being unable to handle more than 1.000.000 (or select any other number) rows by some of the …

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Optimizer hints in MySQL 5.7.7 – The missed manual

In version MySQL 5.7.7 Oracle presented a new promising feature: optimizer hints. However it did not publish any documentation about the hints. The only note which I found in the user manual about the hints …

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Choosing a good sharding key in MongoDB (and MySQL)

MongoDB 3.0 was recently released. Instead of focusing on what’s new – that is so easy to find, let’s rather talk about something that has not changed a lot since the early MongoDB days. This topic …

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Looking deeper into InnoDB’s problem with many row versions

A few days ago I wrote about MySQL performance implications of InnoDB isolation modes and I touched briefly upon the bizarre performance regression I found with InnoDB handling a large amount of versions for a single …

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First TokuMXse performance numbers

UPDATE: Since the publication of this blog post, the first release candidate of TokuMXse was made available for testing. Learn more about v1.0.0.RC.0. In addition, MongoDB has decided to call the release formerly known as v2.8, v3.0. We’ve …

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Getting to know TokuDB for MySQL

During last April’s Percona Live MySQL Conference and Expo, TokuDB celebrated it’s first full-year as an open source storage engine. I still remember reading the official announcement and the expectations it created one year ago. The …

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