Unexpected message: RowDescription

[nicolaerosia]

Anyone saw this before?

    sql_con.execute(insert_stmt, records)
  File "/usr/local/lib/python3.11/site-packages/sqlalchemy/future/engine.py", line 280, in execute
    return self._execute_20(
           ^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/sqlalchemy/engine/base.py", line 1710, in _execute_20
    return meth(self, args_10style, kwargs_10style, execution_options)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/sqlalchemy/sql/elements.py", line 334, in _execute_on_connection
    return connection._execute_clauseelement(
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/sqlalchemy/engine/base.py", line 1577, in _execute_clauseelement
    ret = self._execute_context(
          ^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/sqlalchemy/engine/base.py", line 1953, in _execute_context
    self._handle_dbapi_exception(
  File "/usr/local/lib/python3.11/site-packages/sqlalchemy/engine/base.py", line 2134, in _handle_dbapi_exception
    util.raise_(
  File "/usr/local/lib/python3.11/site-packages/sqlalchemy/util/compat.py", line 211, in raise_
    raise exception
  File "/usr/local/lib/python3.11/site-packages/sqlalchemy/engine/base.py", line 1890, in _execute_context
    self.dialect.do_executemany(
  File "/usr/local/lib/python3.11/site-packages/sqlalchemy/engine/default.py", line 733, in do_executemany
    cursor.executemany(statement, parameters)
  File "/usr/local/lib/python3.11/site-packages/vertica_python/vertica/cursor.py", line 185, in wrap
    return func(self, *args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/vertica_python/vertica/cursor.py", line 319, in executemany
    self.copy(copy_statement, data)
  File "/usr/local/lib/python3.11/site-packages/vertica_python/vertica/cursor.py", line 507, in copy
    raise errors.MessageError('Unexpected message: {0}'.format(message))
sqlalchemy.exc.InternalError: (vertica_python.errors.MessageError) Unexpected message: RowDescription: [
Column(name=OUTPUT, data_type_oid=6, data_type_name=Integer, schema_name=None, table_name=None, table_oid=0, attribute_number=0, precision=None, scale=None, null_ok=True, is_identity=False, format_code=1, internal_size=8, display_size=20)]

[sitingren]

@nicolaerosia Would you please provide the Vertica server version, vertica-python version and a reproducer program?

[nicolaerosia]

@sitingren hello

Unfortunately I cannot reproduce, it only happens from time to time.

Vertica version: Vertica Analytic Database v11.1.1-8
vertica-python: 1.3.5 <- I can try 1.3.6 if you think that will help

[nicolaerosia]

I'm using sqlalchemy on top,

    insert_stmt = sqlalchemy.insert(MyTable).inline()
    records = df.to_dict(orient="records")
    sql_con.execute(insert_stmt, records)

Maybe it's related to .inline() ?

[sitingren]

@nicolaerosia I cannot reproduce with just 3 lines of code. Can you provide a full sqlalchemy program with the definition of MyTable and sample data in df?

[nicolaerosia]

thanks a lot @sitingren , will give it a try :)

As I said, I don't have a reproducer, it happens sporadically.

[sitingren]

There are multiple cases that can trigger Unexpected message: RowDescription error. I don't know which case your sqlalchemy program belongs too. I add improvement in #538 to cover some cases.

[nicolaerosia]

@sitingren I think I found the pattern.

I'm using celery, and sometimes the task takes too much and celery kills the task.
It may be the case that the executing task was in the middle of a SQL Query, then it gets interrupted.

The next task comes, it reuses the previous connection, and it gets unexpected message, the response from previous query?