UndefinedTableError: relation "pg_temp.session_vars" does not exist

[eric-g-97477]

I can successfully connect to a PostgreSQL database and execute queries against a database to view the data the tables contain.

However, when I try to execute an UPDATE, I get the following error:

UndefinedTableError: relation "pg_temp.session_vars" does not exist

I am creating a connection to the database by doing the following:
(nothing special)

    conn = await asyncpg.connect(user='username', 
                                 password='password',
                                 database='databasename', 
                                 host='localhost')

I was wondering what, if anything, you might be aware of that would resolve this issue. Might there be something additional I need to do when setting up the connection?

(I can connect to the database directly via the shell and issue UPDATE's without any problems.)

[elprans]

Please provide error traceback. Does your UPDATE involve a temporary table? What does the query actually look like?

[eric-g-97477]

No, the query does not, as near as I can tell, involve a temporary table...

Query

UPDATE the_table SET the_column = 'new value' WHERE another_column = '42';

Traceback

UndefinedTableError                       Traceback (most recent call last)
/var/folders/7r/z2yvzrzx7_lg2h81285rsplr0000gp/T/ipykernel_40019/3361298876.py in <module>
     32     await conn.close()
     33 
---> 34 asyncio.get_event_loop().run_until_complete(main())

~/depot/vagrant/env_vagrant/lib/python3.10/site-packages/nest_asyncio.py in run_until_complete(self, future)
     68                 raise RuntimeError(
     69                     'Event loop stopped before Future completed.')
---> 70             return f.result()
     71 
     72     def _run_once(self):

~/.pyenv/versions/3.10.0/lib/python3.10/asyncio/futures.py in result(self)
    199         self.__log_traceback = False
    200         if self._exception is not None:
--> 201             raise self._exception
    202         return self._result
    203 

~/.pyenv/versions/3.10.0/lib/python3.10/asyncio/tasks.py in __step(***failed resolving arguments***)
    232                 result = coro.send(None)
    233             else:
--> 234                 result = coro.throw(exc)
    235         except StopIteration as exc:
    236             if self._must_cancel:

/var/folders/7r/z2yvzrzx7_lg2h81285rsplr0000gp/T/ipykernel_40019/3361298876.py in main()
     24     print( query )
     25 
---> 26     result = await conn.execute(query)
     27 
     28     print( result )

~/depot/vagrant/env_vagrant/lib/python3.10/site-packages/asyncpg/connection.py in execute(self, query, timeout, *args)
    316 
    317         if not args:
--> 318             return await self._protocol.query(query, timeout)
    319 
    320         _, status, _ = await self._execute(

~/depot/vagrant/env_vagrant/lib/python3.10/site-packages/asyncpg/protocol/protocol.pyx in query()

~/.pyenv/versions/3.10.0/lib/python3.10/asyncio/futures.py in __await__(self)
    282         if not self.done():
    283             self._asyncio_future_blocking = True
--> 284             yield self  # This tells Task to wait for completion.
    285         if not self.done():
    286             raise RuntimeError("await wasn't used with future")

~/.pyenv/versions/3.10.0/lib/python3.10/asyncio/tasks.py in __wakeup(self, future)
    302     def __wakeup(self, future):
    303         try:
--> 304             future.result()
    305         except BaseException as exc:
    306             # This may also be a cancellation.

~/.pyenv/versions/3.10.0/lib/python3.10/asyncio/futures.py in result(self)
    199         self.__log_traceback = False
    200         if self._exception is not None:
--> 201             raise self._exception
    202         return self._result
    203 

[elprans]

Well, asyncpg itself does not attempt to access any "session_vars" table, so this must be an application error.