Although the spatial extension is designed for geometric data, it is also very conveniently usable for comparing time intervals and other solutions that can be projected onto geometric planes.
The command-line tool is, of course, a good thing - but a graphical environment is even better. This is about a MySQL design environment, or GUI. Exactly what's needed: convenient editing, saving queries, creating connections and synchronising data/structure. And of course - backups. I have to say, this is one of the most successful applications for MySQL that I've come across recently.
This time my interest fell specifically on user-defined variables. They can be broadly divided into two categories: declared variables, used in procedures and functions, and undeclared variables, also used in procedures and functions, but which can be used in an SQL query "in-line".
A problem as old as the world - how to get the next ID value for a table in a MySQL database, given that the ID value is generated as AUTO_INCREMENT.