On 02.05.24 17:23, David G. Johnston wrote: > Version 2 attached. Still a draft, focused on topic picking and overall > structure. Examples and links planned plus the usual semantic markup stuff. > > I chose to add a new sect1 in the user guide (The SQL Language) chapter, > "Data".
Please, let's not.
If a committer wants to state the single place in the documentation to put this I'm content to put it there while leaving my reasoning of choices in place for future bike-shedding. My next options to decide between are the appendix or the lead chapter in Data Types. It really doesn't fit inside DDL IMO which is the only other suggestion I've seen (and an uncertain, or at least unsubstantiated, one) and a new chapter meets both criteria Tom laid out, so long as this is framed as more than just having to document null values.
A stylistic note: "null" is an adjective. You can talk about a "null value" or a value "is null".