Re: PostGIS 3.6.1 - ERROR: operator is not unique: public.geometry = public.geometry

[Cedric Duprez]

Hi Paul,

Thanks for your answer.
The database was restored from a cold physical backup (PGDATA copy).

Cedric

Le 08/01/2026 à 17:25, Paul Ramsey a écrit :

This is odd, I am not able to replicate...

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 POSTGIS="3.6.1dev 3.6.0-6-gdb18a9a49" PGSQL="180" GEOS="3.15.0dev-CAPI-1.21.0" PROJ="9.3.0 NETWORK_ENABLED=ON URL_ENDPOINT=https://cdn.proj.org USER_WRITABLE_DIRECTORY=/Users/pramsey/Library/Application Support/proj DATABASE_PATH=/usr/local/share/proj/proj.db" (compiled against PROJ 9.3.0) LIBXML="2.9.13" LIBJSON="0.17" LIBPROTOBUF="1.4.1" WAGYU="0.5.0 (Internal)"

(1 row)

postgis_reg=# SELECT 'POINT EMPTY'::public.geometry = 'POINT EMPTY'::public.geometry;

 ?column?
----------
 t
(1 row)

Is this a database that has gone through upgrade stages, or a blank fresh database?

P

On Thu, Jan 8, 2026 at 8:21 AM Cedric Duprez <cedric.dup...@ign.fr> wrote:

    Hi all,

    I'm facing a potential bug with PostGIS 3.6.1 on PostgreSQL 17.7.
    Here is what I get with postgis_full_version() : POSTGIS="3.6.1
    f533623" [EXTENSION] PGSQL="170" GEOS="3.12.1-CAPI-1.18.1"
    PROJ="9.4.0 NETWORK_ENABLED=OFF URL_ENDPOINT=https://cdn.proj.org
    USER_WRITABLE_DIRECTORY=/tmp/proj
    DATABASE_PATH=/usr/share/proj/proj.db" (compiled against PROJ
    9.4.0) GDAL="GDAL 3.8.4, released 2024/02/08" LIBXML="2.9.14"
    LIBJSON="0.17" LIBPROTOBUF="1.4.1" WAGYU="0.5.0 (Internal)" RASTER

    When I execute this query:
    SELECT 'POINT EMPTY'::public.geometry = 'POINT
    EMPTY'::public.geometry;
    I get the following error:
    ERROR: operator is not unique: public.geometry = public.geometry

    It seems to be a regression, since I didn't have this error on
    previous versions of PostGIS (3.5).

    How can this problem be solved?
    Thanks in advance for you help,

    Cedric