MySql

Help and howto do things in MySQL

MySQL is the world’s most popular open source database, recognized for its speed and reliability, and is frequently used with PHP to create websites. The Electric Toolbox website uses MySQL as its database backend, and I have personally been using MySQL since 1999. In that time it has proven itself to me to be an extremely fast and reliable database management system, although the earlier versions lacked some features found in other database systems, such as stored procedures, triggers, sub selects and joined table updates. Most of these are available from the 4.1 and 5.0 releases.

If you are looking for MySQL databases – for example geographical databases, I suggest you take a look at SQL Dumpster

MySQL queries to get the local part and domain from an email address

This post shows how to extract the local part and domain name from an email address using MySQL. The local part is the part before the @, for example "chris" in chris@example.com.

MySQL error can’t open file – errno: 24

After some maintenance was done to the virtual host server that one of my virtual servers was running on that required a host reboot, my websites weren’t running due to the MySQL error "[ERROR] /usr/sbin/mysqld: Can’t open file: ‘./databasename/tablename.frm’ (errno: 24)"

PHP PDO class to set the MySQL auto_increment_increment

A few days ago, I posted how to temporarily change the auto increment increment in MySQL. This post has an extension class to PHP's PDO to get the current auto increment value, change it to a new value and then reset it back to the original.

Configuration options to fix some phpMyAdmin annoyances

I use phpMyAdmin as a PHP web based manager for MySQL, but find a few of the default configuration options "out of the box" a little annoying. This post shows some useful modifications to the defaults to make phpMyAdmin more usable, in my opinion.

Cannot load from mysql.proc. The table is probably corrupted

I mistyped the name of an internal MySQL function in some code this morning and got back the error message "Cannot load from mysql.proc. The table is probably corrupted" which appeared to have no bearing on the actual error. The simple fix to this problem is to run the mysql_upgrade command.

List stored procedures in MySQL

This post shows how to get a complete list of stored procedures in a MySQL database and then to see what code is used in the stored procedure.