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Search Results for: duplicate key update

Avoiding auto-increment holes on InnoDB with INSERT IGNORE

Are you using InnoDB tables on MySQL version 5.1.22 or newer? If so, you probably have gaps in your auto-increment columns. A simple INSERT IGNORE query creates gaps for every ignored insert, but this is …

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A Case for Write Optimizations in MySQL

As a storage engine developer, I am excited for MySQL 5.6. Looking at http://dev.mysql.com/tech-resources/articles/whats-new-in-mysql-5.6.html, there has been plenty of work done to improve the performance of reads in MySQL for all storage engines (provided they …

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Using any general purpose computer as a special purpose SIMD computer

Often times, from a computing perspective, one must run a function on a large amount of input. Often times, the same function must be run on many pieces of input, and this is a very …

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Distributed Set Processing with Shard-Query

Can Shard-Query scale to 20 nodes? Peter asked this question in comments to to my previous Shard-Query benchmark. Actually he asked if it could scale to 50, but testing 20 was all I could due …

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The story of one MySQL Upgrade

I recently worked on upgrading MySQL from one of very early MySQL 5.0 versions to Percona Server 5.1. This was a classical upgrade scenario which can cause surprises. Master and few slaves need to be …

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Disk seeks are evil, so let’s avoid them, pt. 4

Continuing in the theme from previous posts, I’d like to examine another case where we can eliminate all disk seeks from a MySQL operation and therefore get two orders-of-magnitude speedup. The general outline of these …

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How many partitions can you have ?

I had an interesting case recently. The customer dealing with large MySQL data warehouse had the table which was had data merged into it with INSERT ON DUPLICATE KEY UPDATE statements. The performance was extremely …

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Quick comparison of MyISAM, Infobright, and MonetDB

Recently I was doing a little work for a client who has MyISAM tables with many columns (the same one Peter wrote about recently). The client’s performance is suffering in part because of the number …

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Innodb performance gotcha w Larger queries.

Couple of days ago I was looking for a way to improve update performance for the application and I was replacing single value UPDATE with multiple value REPLACE (though I also saw the same problem …

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MySQL Users Conference – Innodb

It might look like it is too late to write about stuff happened at Users Conference but I’m just starting find bits of time from processing accumulated backlog. The Theme of this Users Conference was …

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