Version 5.0 (2016-03-20) Changes in the DB-API 2 module (pgdb): "SQL commands are always handled as if they include parameters, i.e. literal percent signs must always be doubled. This consistent behavior is necessary for using pgdb with wrappers like SQLAlchemy."
I'd hope not, as far as the driver is concerned the percent signs are text content. It's plpgsql that is interpreting them directly in the server.
David J.
Hmmm, looking at the code you provided us, it is obviously not what is actually in production. So if you copy the actual function from the system that works
and use that to frop and rebuild the function on the system that fails, does that resolve the problem? I suspect there is an error in the failing system that you have overlooked.