Bug: trailing comma syntax error in postgres_fdw fetch_attstats()

On Sun, Apr 12, 2026 at 10:45 AM SATYANARAYANA NARLAPURAM
<satyanarlapuram@gmail.com> wrote:

When importing statistics from a remote server running PostgreSQL < 17,
fetch_attstats() emits three NULL placeholders for the range statistics
columns that don't exist on older servers. The string literal included a trailing
comma after the last NULL, producing invalid SQL:

SELECT ... NULL, NULL, NULL, FROM pg_catalog.pg_stats ...

This fails ANALYZE or IMPORT STATISTICS on a foreign table backed
by a pre-v17 remote server with a syntax error.

My bad, I will take care of this. I added it to the open item.

Thanks for the report and patch!

Best regards,
Etsuro Fujita

On Sun, Apr 12, 2026 at 3:40 PM Etsuro Fujita <etsuro.fujita@gmail.com> wrote:

On Sun, Apr 12, 2026 at 10:45 AM SATYANARAYANA NARLAPURAM
<satyanarlapuram@gmail.com> wrote:

When importing statistics from a remote server running PostgreSQL < 17,
fetch_attstats() emits three NULL placeholders for the range statistics
columns that don't exist on older servers. The string literal included a trailing
comma after the last NULL, producing invalid SQL:

SELECT ... NULL, NULL, NULL, FROM pg_catalog.pg_stats ...

This fails ANALYZE or IMPORT STATISTICS on a foreign table backed
by a pre-v17 remote server with a syntax error.

My bad, I will take care of this.

The patch looks good to me. I will push it if there are no objections.

Best regards,
Etsuro Fujita