"David G. Johnston" <david.g.johnston@gmail.com> writes:
> On Thu, Sep 30, 2021 at 2:51 PM PG Bug reporting form <
> noreply@postgresql.org> wrote:
>> I get the ERROR : the function array_cat(anyarray, anyarray) does not
>> exist,
> You may find this commit to be illuminating. Work was done in this area
> for v14.
> https://github.com/postgres/postgres/commit/97f73a978fc1aca59c6ad765548ce0096d95a923
This one might be more so:
https://git.postgresql.org/gitweb/?p=postgresql.git&a=commitdiff&h=9e38c2bb50
Also see the very first item in the v14 compatibility notes:
User-defined objects that reference certain built-in array functions
along with their argument types must be recreated (Tom Lane)
Specifically, array_append(), array_prepend(), array_cat(),
array_position(), array_positions(), array_remove(), array_replace(),
and width_bucket() used to take anyarray arguments but now take
anycompatiblearray. Therefore, user-defined objects like aggregates
and operators that reference those array function signatures must be
dropped before upgrading, and recreated once the upgrade completes.
regards, tom lane