On Tuesday, July 21, 2020, Justin Pryzby <pryzby(at)telsasoft(dot)com> wrote:
> We hit this on v13b2 and verified it fails on today's HEAD (ac25e7b039).
>
> explain SELECT 1 FROM sites NATURAL JOIN sectors WHERE
> sites.config_site_name != sectors.sect_name ;
> ERROR: could not determine which collation to use for string comparison
>
> I can workaround the issue by DELETEing stats for either column.
>
> It's possible we're doing soemthing wrong and I need to revisit docs..but
> this
> was working in v12.
>
This sounds suspiciously like a side-effect of:
https://git.postgresql.org/gitweb/?p=postgresql.git;a=commitdiff;h=022cd0bfd33968f2b004106cfeaa3b2951e7f322
David J.