PG Doc comments form <noreply@postgresql.org> writes:
> I am building a PostgreSQL parser and need a precise reference for the
> formal syntax of condition used in the WHERE clause.
We do not have one. You might be able to extract what you need from
our Bison grammar though:
https://git.postgresql.org/gitweb/?p=postgresql.git;a=blob;f=src/backend/parser/gram.y;h=d7f9c00c4099bd86c39ce79c997123a2a0ca6782;hb=HEAD
starting more or less from the a_expr production.
Keep in mind that this is a moving target, as we frequently add
new syntax features.
regards, tom lane