> That might've worked back before the driver did real prepared
> statements. It's invalid syntax though, because typename before the
> constant works only for simple literal string constants. You got away
> with it when the driver interpolated parameter values into the query as
> string literals, but you can't do it anymore.
>
> ?::interval (or the full-blown CAST syntax) is the right way.
>
> See
> http://developer.postgresql.org/pgdocs/postgres/sql-syntax-lexical.html#SQL-SYNTAX-CONSTANTS
> particularly 4.1.2.5.
Thank you for the clarification.
-- m@