swcarpentry/bc — pull request #721 by ethanwhite (2014-09-17 02:50:12+00:00)
Title: Add UPDATE to SQL lessons

When showing students how to add and remove records it will be natural for
them to ask how to modify an existing record. This demonstrates how to do
this using Update in a few lines.

To avoid the relevant lesson becoming too much of a wall of text, this also
splits the lesson into two sections.