Viktor Rosenfeld <listuser36(at)googlemail(dot)com> writes:
> annis=> select array_agg(array['a'::varchar, 'b', 'c']);
> ERROR: could not find array type for data type character varying[]
> Why doesn't this work?
The output of array_agg would have to be an array whose elements
are array-of-varchar. Which is a datatype we don't have.
(2-D array is a different concept...)
regards, tom lane