2010/5/14 Tom Lane <[email protected]>: > Robert Haas <[email protected]> writes: >> On Thu, May 13, 2010 at 9:47 PM, Joseph Adams >> <[email protected]> wrote: >>> [] retrieves a value of a JSON array/object by (one-based) index. In >>> other words, value[n] is equivalent to selecting the nth row of >>> json_values(value) (provided value is of type JSON). Examples: >>> >>> SELECT ('[1,2,3,4]'::JSON)[3] >>> -- Result is '3'::JSON >>> >>> SELECT ('{"a": 1, "b": 2, "c": 3, "d": 4}'::JSON)[3] >>> -- Result is '3'::JSON > >> I think some kind of array deference and object deference mechanism is >> absolutely, positively 100% required. I don't know whether the >> particular syntax you've proposed here is best or whether we should >> pick another syntax or just use function notation, but I think we >> definitely need *something*. > > Trying to use array notation on something that isn't a SQL array type > is guaranteed to be a mess. I strongly recommend that you not attempt > that. Just define a function for it.
I agree. Maybe you can implement cast to hstore datatype. Regards Pavel Stehule > > regards, tom lane > > -- > Sent via pgsql-hackers mailing list ([email protected]) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-hackers > -- Sent via pgsql-hackers mailing list ([email protected]) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
