On 5/28/22 12:38, Shaheed Haque wrote:
> Tom,
>
> Thanks for the considered advice and insights. My takeaway is that
> based on what I've said,you are mostly unsurprised by the results I
> see. In the longer term, the number of rows will increase but I will
> have to ponder options for the immediate future. I'll have a play with
> the knobs you suggested and will report back with anything of note.
>
> One last thought about TOAST. If the cost of the -> retrieving the
> data cannot be obviated, is there any way to tweak how that works?
See:
https://www.postgresql.org/docs/current/storage-toast.html
and from there:
https://www.postgresql.org/docs/current/sql-altertable.html
Search for SET STORAGE.
It might help with(from Tom Lane):
"Unfortunately the planner doesn't account
for detoasting costs when making such estimates, ..."
but probably not much with:
" ...because anything at all that you do with
that big JSONB column is going to be expensive. (Another thing
that's been on the to-do list for awhile is enabling partial
retrieval of large JSONB values, but AFAIK that hasn't happened
yet either.)
>
> Thanks, Shaheed
>
--
Adrian Klaver
adrian.klaver@aklaver.com