Re: jsonb format is pessimal for toast compression

On Thu, Aug 14, 2014 at 4:24 PM, Claudio Freire <klaussfreire@gmail.com> wrote:
> On Thu, Aug 14, 2014 at 3:49 PM, Larry White <ljw1001@gmail.com> wrote:
>> I attached a json file of approximately 513K. It contains two repetitions of
>> a single json structure. The values are quasi-random. It might make a decent
>> test case of meaningfully sized data.
>
>
> I have a 59M in plain SQL (10M compressed, 51M on-disk table size)
> collection of real-world JSON data.
>
> This data is mostly counters and anciliary info stored in json for the
> flexibility, more than anything else, since it's otherwise quite
> structured: most values share a lot between each other (in key names)
> but there's not much redundancy within single rows.
>
> Value length stats (in text format):
>
> min: 14
> avg: 427
> max: 23239
>
> If anyone's interested, contact me personally (I gotta anonimize the
> info a bit first, since it's production info, and it's too big to
> attach on the ML).

Oh, that one has a 13k toast, not very interesting.

But I've got another (very similar), 47M table, 40M toast, length distribution:

min: 19
avg: 474
max: 20370

Not sure why it's got a bigger toast having a similar distribution.
Tells just how meaningless min/avg/max stats are :(