When people ask me how to learn to use a database or how to write SQL queries, I tell them to pick a database system and immerse themselves in it. In fact that advice goes for a lot of software technologies: just immerse yourself in a language, as programming tutorials are easy to come [...]

In Part 1 of The Joy of Null I discussed a variety of ways null-equivalent values make it into the software design. Often times, developer laziness or immutability of the database tier drives many developers to insert values that simulate null values, rather than using a database null itself. In this second half, [...]

Often in the database world, you do not have all the information needed to create a record. For example, you may have a person’s full name but not their middle name or initial, or you might be missing their date of birth. In such cases, the recommended solution is to fill that field [...]