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MySQL

MySQL performance tuning and optimization: optimize MySQL server and database

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How to fix System.Collections.Generic.KeyNotFoundException “The given key was not present in the dictionary” Exception with MySQL Connector/NET and utf8mb4 character set

An System.Collections.Generic.KeyNotFoundException “The given key was not present in the dictionary” can be the result of using a too old MySQL Connector/NET version in your ASP.NET web application. A KeyNotFoundException is thrown when an operation attempts to retrieve an element from a collection using a key that does not exist in that collection. An unsupported character set like utf8mb4 can be such a key, if your Connector/NET doesn’t support this character set. Luckily there is an easy workaround for this.

MySQL InnoDB performance improvement: InnoDB buffer pool instances – Updated!

High Performance MySQL

Are you running into MySQL load problems? Learn how to tune MySQL servers for a heavy InnoDB workload, by configuring innodb_buffer_pool_instances and increasing read/write I/O threads. Dividing the InnoDB buffer pool into multiple instances can improve Disk I/O. By doing so, you run your database more efficiently and faster. Here is a little help for you.

Convert MySQL MyISAM tables to InnoDB

High Performance MySQL

In the earlier days of MySQL, the default storage engine for your database tables was “MyISAM”. InnoDB is the engine to use now, and MyISAM is no longer actively developed. Therefore all MySQL optimizations are for InnoDB, and it’s recommended to switch from MyISAM to this InnoDB storage engine for your MySQL database tables. Follow this tutorial on how to convert from MyISAM to InnoDB.

How to flush MySQL query cache from time to time

High Performance MySQL

From time to time you need to flush MySQL’s query_cache to prevent fragmentation of free query cache memory space. Whether we need to flush the query cache is provided to us by MySQL’s Qcache_free_blocks status information. The higher the value the more fragmented free space is. In this post, you’ll learn how to flush the MySQL query cache unattended / automatic through a Linux cronjob and manually on the MySQL shell.

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