Re: list of extended statistics on psql

On Sun, Aug 30, 2020 at 12:33:29PM -0400, Alvaro Herrera wrote:
>On 2020-Aug-30, Tomas Vondra wrote:
>
>> On Sat, Aug 29, 2020 at 06:43:47PM -0400, Alvaro Herrera wrote:
>> > On 2020-Aug-29, Tomas Vondra wrote:
>
>> > > Also, it might be useful to show the size of the statistics built, just
>> > > like we show for \d+ etc.
>> >
>> > \dX+ I suppose?
>>
>> Right. I've only used \d+ as an example of an existing command showing
>> sizes of the objects.
>
>Yeah, I understood it that way too.
>
>How can you measure the size of the stat objects in a query? Are you
>thinking in pg_column_size()?
>

Either that or simply length() on the bytea value.

>I wonder how to report that. Knowing that psql \-commands are not meant
>for anything other than human consumption, maybe we can use a format()
>string that says "built: %d bytes" when \dX+ is used (for each stat type),
>and just "built" when \dX is used. What do people think about this?
>

I'd use the same approach as \d+, i.e. a separate column with the size.
Maybe that'd mean too many columns, though.

regards

--
Tomas Vondra http://www.2ndQuadrant.com
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