Re: [BUGS] BUG #14545: Unable to retrieve parameter mode 'VARIADIC'

I don't have access to an authoritative definition for what the allowed values for information_schema.parameters.parameter_mode are.​

The fact that our "VARIADIC" mode maps to "IN" on the information schema is not accidental.  The question is whether it is out-of-date.  Tom Lane committed that particular change back in 2008 (d89737d3) though the file header suggests it conforms to the ISO/IEC 9075-11:2011 specification.

Is there a reason you don't just use the PostgreSQL catalogs?  Are you aware of other implementations of information schema that have this level of detail?

Changing the value from "IN" to "VARIADIC" would be a breaking change for systems that only care about the "IN" property of the argument.  Even matching the standard on this topic might not be warranted given 9 years of the present behavior.  Without even that benefit the hurdle to change this is extremely high - especially when pg_proc is authoritative from our internal perspective.

David J.