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Search Results for: slow insert

Why “insert … on duplicate key update” May Be Slow, by Incurring Disk Seeks

In my post on June 18th, I explained why the semantics of normal ad-hoc insertions with a primary key are expensive because they require disk seeks on large data sets. I previously explained why it …

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Tools and tips for analysis of MySQL’s Slow Query Log

MySQL has a nice feature, slow query log, which allows you to log all queries that exceed a predefined about of time to execute. Peter Zaitsev first wrote about this back in 2006 – there …

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Analyzing Slow Query Table in MySQL 5.6

Next week I’m teaching an online Percona Training class, called Analyzing SQL Queries with Percona Toolkit.  This is a guided tour of best practices for pt-query-digest, the best tool for evaluating where your database response time …

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MySQL on Amazon RDS part 1: insert performance

Amazon’s Relational Database Service (RDS) is a cloud-hosted MySQL solution. I’ve had some clients hitting performance limitations on standard EC2 servers with EBS volumes (see SSD versus EBS death match), and one of them wanted …

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On “Replace Into”, “Insert Ignore”, Triggers, and Row Based Replication

In posts on June 30 and July 6, I explained how implementing the commands “replace into” and “insert ignore” with TokuDB’s fractal trees data structures can be two orders of magnitude faster than implementing them …

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TokuDB speeds up “replace” and “insert ignore” operations by relaxing the affected rows constraint

In posts on June 30 and July 6, we explained how implementing the commands “replace into” and “insert ignore” with TokuDB’s fractal trees data structures can be two orders of magnitude faster than implementing them …

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Some little known facts about Innodb Insert Buffer

Despite being standard Innodb feature forever Insert Buffers remains some kind of mysterious thing for a lot of people, so let me try to explain thing a little bit. Innodb uses insert buffer to “cheat” …

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Tradeoff: Insertions versus Point Queries

I’ve been waving my hands about lower bounds. Well, sometimes I haven’t been waving my hands, because the lower bounds are tight. But in other cases (lenient insertions, range queries), the lower bounds are very …

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MySQL Slow query log in the table

As of MySQL 5.1 get MySQL slow query log logged in mysql.slow_log table instead of the file as you had in previous versions. We rarely would use this feature as it is incompatible with our …

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Slow Query Log analyzes tools

(There is an updated version of this post here). MySQL has simple but quite handy feature – slow query log, which allows you to log all queries which took over define number of seconds to …

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