Andrew Dunstan <andrew(at)dunslane(dot)net> writes:
> Fix documentation of argument type of json_agg and jsonb_agg
> json_agg was originally designed to aggregate records. However, it soon
> became clear that it is useful for aggregating all kinds of values and
> that's what we have on 9.3 and 9.4, and in head for it and jsonb_agg.
> The documentation suggested otherwise, so this fixes it.
Claiming that the argument type is "expression" is not a fix. I don't
mind using that terminology in the first table column, but the second
column is supposed to be the truth not handwaving.
The actual declaration of the argument type is "anyelement", and I think
we use that to document other such functions.
regards, tom lane