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.
Category: MySQL
MySQL performance tuning and optimization: optimize MySQL server and database

Restore single MySQL table from a full mysqldump backup file
Here are the steps required to restore a single MySQL table from a full mysqldump database backup file on the command-line. If you need to restore a single table from a full MySQL backup, you may find yourself wondering “how do I do that?”. There are a few steps required, I outline them here for you to restore the contents of just one table back into the database from the mysqldump using Bash.

MySQL InnoDB performance improvement: InnoDB buffer pool instances – Updated!
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.
MySQL DoS in the Procedure Analyse Function – CVE-2015-4870
Sri Lankan Security researcher Osanda Malith discovered a DoS -or crash- vulnerability in MySQL’s Procedure Analyse Function. The vulnerability crashes MySQL versions up to 5.5.45.
How to string replace on all WordPress posts in MySQL
Replace all instances of a string in WordPress using phpMyAdmin and SQL statements, or a WordPress plugin. Learn how to replace content in your MySQL database in bulk with MySQL REPLACE.

MySQL database optimization with indices
MySQL indexes (indices) are important. Why? Because they speed up the process for MySQL to find requested information.

Convert MySQL MyISAM tables to InnoDB
Convert MyISAM to InnoDB for better database performance. 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
Flush MySQL query_cache to prevent fragmentation of free query cache memory space. Flushing the query cache with flush query cache does not delete or clear the query cache. You have to use reset query cache to fully clear MySQL’s query cache.

Check, repair and optimize MySQL tables with mysqlcheck
Check, repair and optimize MySQL tables with mysqlcheck. The mysqlcheck client is a command line table maintenance program for MySQL. Mysqlcheck checks, repairs, optimizes, or analyzes MySQL tables. In this post I’ll show you how to use mysqlcheck to optimize all MySQL tables using a cronjob.
How to compare MD5 and SHA1 hashes in MySQL
Some web scripting languages, such as classic ASP, don’t have native string hashing functions – like MD5 or SHA1. This makes it quite difficult to hash or encrypt user supplied input, and to perform string comparison to compare hashes. Let’s make MySQL do the string comparison and hash calculations for us!