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
I recently looked at how to default a column as a UUID/GUID in MySQL using a trigger, but it’s not replication safe when using statement based replication. This post looks at an alternative to using triggers by using a variable instead.
It’s possible to temporarily change MySQL’s auto increment increment value to something other than the system setting. This might be useful if (like me) you have two MySQL databases set up in a master-master relationship with an increment of 2, but need to increment a table in 1s.
When attempting to load a database dumped with mysqldump into an older MySQL database, I got the error message ERROR 1115 (42000) : Unknown character set: ‘utf8mb4’ in mysql.
When using the mysqldump command to make a back of the mysql database, you might get the message "Warning: Skipping the data of table mysql.event. Specify the –events option explicitly". This post shows how to suppress this message.
The events table was introduced to MySQL in 5.1.6 and when upgrading you will start to see the warning "Warning: Skipping the data of table mysql.event" when using mysqldump. This is not an error as such, but more to make it clear to you that something has changed.
If you order a string column that contains only numeric values with MySQL, it will order them as string values, e.g.: 1, 10, 100, 2, 3, 31, 32, 4, etc. If you want to order them as if they were an integer, cast them in the order by clause.
