解决sqlalchemy.exc.OperationalError: (_mysql_exceptions.OperationalError) (2027, 'Malformed packet')

Traceback (most recent call last):
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/engine/base.py", line 1193, in _execute_context
    context)
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/engine/default.py", line 507, in do_execute
    cursor.execute(statement, parameters)
  File "/usr/local/lib/python3.7/site-packages/MySQLdb/cursors.py", line 250, in execute
    self.errorhandler(self, exc, value)
  File "/usr/local/lib/python3.7/site-packages/MySQLdb/connections.py", line 50, in defaulterrorhandler
    raise errorvalue
  File "/usr/local/lib/python3.7/site-packages/MySQLdb/cursors.py", line 247, in execute
    res = self._query(query)
  File "/usr/local/lib/python3.7/site-packages/MySQLdb/cursors.py", line 411, in _query
    rowcount = self._do_query(q)
  File "/usr/local/lib/python3.7/site-packages/MySQLdb/cursors.py", line 374, in _do_query
    db.query(q)
  File "/usr/local/lib/python3.7/site-packages/MySQLdb/connections.py", line 277, in query
    _mysql.connection.query(self, query)
_mysql_exceptions.OperationalError: (2027, 'Malformed packet')

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "api.py", line 200, in
    init_db()
  File "api.py", line 42, in init_db
    DatabaseConfigs.database_name == 'redis').first().to_dict()
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/orm/query.py", line 2825, in first
    ret = list(self[0:1])
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/orm/query.py", line 2617, in __getitem__
    return list(res)
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/orm/query.py", line 2925, in __iter__
    return self._execute_and_instances(context)
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/orm/query.py", line 2948, in _execute_and_instances
    result = conn.execute(querycontext.statement, self._params)
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/engine/base.py", line 948, in execute
    return meth(self, multiparams, params)
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/sql/elements.py", line 269, in _execute_on_connection
    return connection._execute_clauseelement(self, multiparams, params)
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/engine/base.py", line 1060, in _execute_clauseelement
    compiled_sql, distilled_params
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/engine/base.py", line 1200, in _execute_context
    context)
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/engine/base.py", line 1413, in _handle_dbapi_exception
    exc_info
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/util/compat.py", line 203, in raise_from_cause
    reraise(type(exception), exception, tb=exc_tb, cause=cause)
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/util/compat.py", line 186, in reraise
    raise value.with_traceback(tb)
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/engine/base.py", line 1193, in _execute_context
    context)
  File "/usr/local/lib/python3.7/site-packages/sqlalchemy/engine/default.py", line 507, in do_execute
    cursor.execute(statement, parameters)
  File "/usr/local/lib/python3.7/site-packages/MySQLdb/cursors.py", line 250, in execute
    self.errorhandler(self, exc, value)
  File "/usr/local/lib/python3.7/site-packages/MySQLdb/connections.py", line 50, in defaulterrorhandler
    raise errorvalue
  File "/usr/local/lib/python3.7/site-packages/MySQLdb/cursors.py", line 247, in execute
    res = self._query(query)
  File "/usr/local/lib/python3.7/site-packages/MySQLdb/cursors.py", line 411, in _query
    rowcount = self._do_query(q)
  File "/usr/local/lib/python3.7/site-packages/MySQLdb/cursors.py", line 374, in _do_query
    db.query(q)
  File "/usr/local/lib/python3.7/site-packages/MySQLdb/connections.py", line 277, in query
    _mysql.connection.query(self, query)
sqlalchemy.exc.OperationalError: (_mysql_exceptions.OperationalError) (2027, 'Malformed packet') [SQL: 'SELECT all_database_configs.id AS all_database_configs_id, all_database_configs.database_name AS all_database_configs_databas
e_name, all_database_configs.config_dict AS all_database_configs_config_dict \nFROM all_database_configs \nWHERE all_database_configs.database_name = %s \n LIMIT %s'] [parameters: ('redis', 1)] (Background on this error at: http:
//sqlalche.me/e/e3q8)
 

该错误是由于数据库驱动版本与Python使用的驱动版本不兼容导致的，连接失效问题，典型特征使用连接执行一次操作后再执行低二次操作报次错误，解决方案换低版本的数据库连接试试。