On Tuesday, June 18, 2024, Tom Lane <t...@sss.pgh.pa.us> wrote: > Yugo NAGATA <nag...@sraoss.co.jp> writes: > > On Tue, 18 Jun 2024 20:56:58 -0700 > > "David G. Johnston" <david.g.johns...@gmail.com> wrote: > >> But it is neither a keyword nor an identifier. > > The lexer would be quite surprised by your claim that NULL isn't > a keyword. Per src/include/parser/kwlist.h, NULL is a keyword, > and a fully reserved one at that. > > >
Can’t it be both a value and a keyword? I figured the not null constraint and is null predicates are why it’s a keyword but the existence of those doesn’t cover its usage as a literal value that can be stuck anywhere you have an expression. David J.
