Re: Statistics Import and Export

>
>
> > WARNING: invalid input syntax for type integer: "four"
> > row_written | stats_applied |
> > stats_rejected | params_rejected
> > -------------+----------------------------------+--------------------
> > ------------------+-----------------
> > t | {null_frac,avg_width,n_distinct} |
> > {most_common_vals,most_common_freqs} |
> > (1 row)
>
> I think I like this, as well, except for the return value, which seems
> like too much information and a bit over-engineered. Can we simplify it
> to what's actually going to be used by pg_upgrade and other tools?
>

pg_upgrade currently won't need any of it, it currently does nothing when a
statistics import fails. But it could do *something* based on this
information. For example, we might have an option
--analyze-tables-that-have-a-statistics-import-failure that analyzes tables
that have at least one statistics that didn't import. For instance,
postgres_fdw may try to do stats import first, and if that fails fall back
to a remote table sample.

We could do other things. It seems a shame to just throw away this
information when it could potentially be used in the future.

>
> > Attached is v25.
>
> I believe 0001 and 0002 are in good shape API-wise, and I can start
> getting those committed. I will try to clean up the code in the
> process.
>

:)