Wow, thanks for that info, very useful. When you say “I really hope they open source that part”, do you mean the mechanism to plug other dialects in, or the PostgreSQL interface?
I mean the postgres parser (and semantic changes) for ZetaSQL. The zetasql parser is in a file called zetasql/parser/bison_parser.y, I strongly suspect they now have a file called something like zetasql/pgparser/bison_parser.y as well (and much more pervasive changes to support the deeper differences in the dialects).
This is the lexical structure and syntax docs for the new postgres inteface to cloud spanner:
This is the lexical structure and syntax docs for the new postgres inteface to cloud spanner:
https://cloud.google.com/spanner/docs/postgresql/lexical
And this is the zetasql lexical structure and syntax docs:
https://github.com/google/zetasql/blob/master/docs/lexical.m...
Notice that the new PG docs are an edit of the Zeta ones - evidence that my hypothesis is correct.