Dragos Valentin Moinescu <dragos(dot)moinescu(at)gmail(dot)com> writes:
> The thing is that I cannot catch the exception raised by plpy.execute().
Yeah, plpython's error handling is fundamentally broken. Somebody
needs to rewrite it to be more like the other PLs. In the meantime,
I'd suggest using plperl, which has gotten a lot more love than
plpython ever did.
regards, tom lane