FATAL: simple query "BEGIN" arrived before ending an extended query message

Hi all,

Recently we started seeing errors from pgpool-II stating 'FATAL: simple
query "BEGIN" arrived before ending an extended query message'. These
errors started occurring after upgrading PgJDBC from 42.7.5 to 42.7.7. I've
created the following ticket at PgJDBC:
https://github.com/pgjdbc/pgjdbc/issues/3724 . It was closed as a duplicate
of https://github.com/pgjdbc/pgjdbc/issues/3107 , which describes a similar
issue and was opened by Tatsuo Ishii.

The problem however, is that previously the error was only triggered when
using autosave, which is not a common setup, but now the error is triggered
even when using default configuration. This makes it impossible to combine
PgJDBC 42.7.6 and up with pgpool-II. I do not know what the plans are on
this from the side of PostgreSQL and PgJDBC, but I just wanted to raise
some awareness on this issue here. IMHO PostgreSQL should either explicitly
allow this (in which case pgpool-II needs to be fixed) or explicitly
disallow it (in which case PgJDBC needs to be fixed). The current situation
is no good as we now simply cannot upgrade PgJDBC anymore (and the same
will be true for all other users of pgpool-II).

Best regards,
Emond Papegaaij