mysql 无法使用sqlalchemy创建表

bq8i3lrv  于 2024-01-05  发布在  Mysql
关注(0)|答案(1)|浏览(187)

我试图通过使用sqlalchemy创建mysql数据库，并运行到这个错误。添加一个错误的完整追溯：

  1. Traceback (most recent call last):
  2.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\engine\base.py", line 145, in __init__
  3.     self._dbapi_connection = engine.raw_connection()
  4.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\engine\base.py", line 3292, in raw_connection
  5.     return self.pool.connect()
  6.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\pool\base.py", line 452, in connect
  7.     return _ConnectionFairy._checkout(self)
  8.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\pool\base.py", line 1269, in _checkout
  9.     fairy = _ConnectionRecord.checkout(pool)
  10.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\pool\base.py", line 716, in checkout
  11.     rec = pool._do_get()
  12.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\pool\impl.py", line 169, in _do_get
  13.     with util.safe_reraise():
  14.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\util\langhelpers.py", line 146, in __exit__
  15.     raise exc_value.with_traceback(exc_tb)
  16.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\pool\impl.py", line 167, in _do_get
  17.     return self._create_connection()
  18.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\pool\base.py", line 393, in _create_connection
  19.     return _ConnectionRecord(self)
  20.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\pool\base.py", line 678, in __init__
  21.     self.__connect()
  22.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\pool\base.py", line 902, in __connect
  23.     with util.safe_reraise():
  24.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\util\langhelpers.py", line 146, in __exit__
  25.     raise exc_value.with_traceback(exc_tb)
  26.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\pool\base.py", line 898, in __connect
  27.     self.dbapi_connection = connection = pool._invoke_creator(self)
  28.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\engine\create.py", line 637, in connect
  29.     return dialect.connect(*cargs, **cparams)
  30.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\engine\default.py", line 616, in connect
  31.     return self.loaded_dbapi.connect(*cargs, **cparams)
  32.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\pymysql\connections.py", line 353, in __init__
  33.     self.connect()
  34.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\pymysql\connections.py", line 633, in connect
  35.     self._request_authentication()
  36.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\pymysql\connections.py", line 932, in _request_authentication
  37.     auth_packet = _auth.caching_sha2_password_auth(self, auth_packet)
  38.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\pymysql\_auth.py", line 239, in caching_sha2_password_auth
  39.     pkt = conn._read_packet()
  40.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\pymysql\connections.py", line 725, in _read_packet
  41.     packet.raise_for_error()
  42.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\pymysql\protocol.py", line 221, in raise_for_error
  43.     err.raise_mysql_exception(self._data)
  44.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\pymysql\err.py", line 143, in raise_mysql_exception
  45.     raise errorclass(errno, errval)
  46. pymysql.err.OperationalError: (1049, "Unknown database 'books'")
  47. The above exception was the direct cause of the following exception:
  48. Traceback (most recent call last):
  49.   File "C:\Program Files\JetBrains\PyCharm 2023.3\plugins\python\helpers\pydev\pydevconsole.py", line 364, in runcode
  50.     coro = func()
  51.   File "<input>", line 1, in <module>
  52.   File "C:\Program Files\JetBrains\PyCharm 2023.3\plugins\python\helpers\pydev\_pydev_bundle\pydev_umd.py", line 197, in runfile
  53.     pydev_imports.execfile(filename, global_vars, local_vars)  # execute the script
  54.   File "C:\Program Files\JetBrains\PyCharm 2023.3\plugins\python\helpers\pydev\_pydev_imps\_pydev_execfile.py", line 18, in execfile
  55.     exec(compile(contents+"\n", file, 'exec'), glob, loc)
  56.   File "C:\Users\baron\Python_Darbai\Turing_college\GIT\Sprint_3\dbaron-DE1.3\test_db_creaton.py", line 183, in <module>
  57.     db_manager.create_database()
  58.   File "C:\Users\baron\Python_Darbai\Turing_college\GIT\Sprint_3\dbaron-DE1.3\test_db_creaton.py", line 29, in create_database
  59.     self.session.execute(create_database_query)
  60.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\orm\session.py", line 2308, in execute
  61.     return self._execute_internal(
  62.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\orm\session.py", line 2180, in _execute_internal
  63.     conn = self._connection_for_bind(bind)
  64.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\orm\session.py", line 2047, in _connection_for_bind
  65.     return trans._connection_for_bind(engine, execution_options)
  66.   File "<string>", line 2, in _connection_for_bind
  67.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\orm\state_changes.py", line 139, in _go
  68.     ret_value = fn(self, *arg, **kw)
  69.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\orm\session.py", line 1143, in _connection_for_bind
  70.     conn = bind.connect()
  71.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\engine\base.py", line 3268, in connect
  72.     return self._connection_cls(self)
  73.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\engine\base.py", line 147, in __init__
  74.     Connection._handle_dbapi_exception_noconnection(
  75.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\engine\base.py", line 2430, in _handle_dbapi_exception_noconnection
  76.     raise sqlalchemy_exception.with_traceback(exc_info[2]) from e
  77.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\engine\base.py", line 145, in __init__
  78.     self._dbapi_connection = engine.raw_connection()
  79.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\engine\base.py", line 3292, in raw_connection
  80.     return self.pool.connect()
  81.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\pool\base.py", line 452, in connect
  82.     return _ConnectionFairy._checkout(self)
  83.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\pool\base.py", line 1269, in _checkout
  84.     fairy = _ConnectionRecord.checkout(pool)
  85.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\pool\base.py", line 716, in checkout
  86.     rec = pool._do_get()
  87.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\pool\impl.py", line 169, in _do_get
  88.     with util.safe_reraise():
  89.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\util\langhelpers.py", line 146, in __exit__
  90.     raise exc_value.with_traceback(exc_tb)
  91.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\pool\impl.py", line 167, in _do_get
  92.     return self._create_connection()
  93.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\pool\base.py", line 393, in _create_connection
  94.     return _ConnectionRecord(self)
  95.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\pool\base.py", line 678, in __init__
  96.     self.__connect()
  97.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\pool\base.py", line 902, in __connect
  98.     with util.safe_reraise():
  99.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\util\langhelpers.py", line 146, in __exit__
  100.     raise exc_value.with_traceback(exc_tb)
  101.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\pool\base.py", line 898, in __connect
  102.     self.dbapi_connection = connection = pool._invoke_creator(self)
  103.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\engine\create.py", line 637, in connect
  104.     return dialect.connect(*cargs, **cparams)
  105.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\sqlalchemy\engine\default.py", line 616, in connect
  106.     return self.loaded_dbapi.connect(*cargs, **cparams)
  107.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\pymysql\connections.py", line 353, in __init__
  108.     self.connect()
  109.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\pymysql\connections.py", line 633, in connect
  110.     self._request_authentication()
  111.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\pymysql\connections.py", line 932, in _request_authentication
  112.     auth_packet = _auth.caching_sha2_password_auth(self, auth_packet)
  113.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\pymysql\_auth.py", line 239, in caching_sha2_password_auth
  114.     pkt = conn._read_packet()
  115.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\pymysql\connections.py", line 725, in _read_packet
  116.     packet.raise_for_error()
  117.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\pymysql\protocol.py", line 221, in raise_for_error
  118.     err.raise_mysql_exception(self._data)
  119.   File "C:\Users\baron\AppData\Local\Programs\Python\Python310\lib\site-packages\pymysql\err.py", line 143, in raise_mysql_exception
  120.     raise errorclass(errno, errval)
  121. sqlalchemy.exc.OperationalError: (pymysql.err.OperationalError) (1049, "Unknown database 'books'")
  122. (Background on this error at: https://sqlalche.me/e/20/e3q8)

字符串
所有数据库凭据都在. env文件中。添加代码片段，可能有问题：

  1. from sqlalchemy import Column, Integer, String, ForeignKey, Float
  2. from sqlalchemy.orm import relationship, declarative_base
  3. import os
  4. from dotenv import load_dotenv
  5. from sqlalchemy import create_engine, text
  6. from sqlalchemy.orm import sessionmaker
  7. import pymysql
  9. Base = declarative_base()
  11. class DatabaseManager:
  12.     def __init__(self):
  13.         load_dotenv()
  15.         self.root_username = os.getenv("ROOT_USERNAME")
  16.         self.root_password = os.getenv("ROOT_PASSWORD")
  17.         self.new_database = os.getenv("NEW_DATABASE")
  19.         if None in [self.root_username, self.root_password, self.new_database]:
  20.             raise ValueError("Missing environment variables")
  22.         self.DB_URI = f"mysql+pymysql://{self.root_username}:{self.root_password}@localhost/{self.new_database}"
  23.         self.engine = create_engine(self.DB_URI, echo=True)
  24.         self.Session = sessionmaker(bind=self.engine)
  25.         self.session = self.Session()
  27.     def create_database(self):
  28.         create_database_query = text(f"CREATE DATABASE IF NOT EXISTS {self.new_database}")
  29.         self.session.execute(create_database_query)
  30.         self.session.commit()
  32.     def create_tables(self):
  33.         Base.metadata.create_all(self.engine)
  35.     def close_connection(self):
  36.         self.session.close()

型
我的这部分代码有什么问题（没有全部添加，因为它太长了，而且基本上只有表）？

mysql

1条答案

按热度按时间
mwg9r5ms

mwg9r5ms1#

在运行这段代码之前，您必须创建数据库books。SQLAlchemy不会为您创建数据库，它认为数据库已经存在

赞(0）分享  回复(0）举报  2024-01-05
我来回答

相关问题

    查看更多

    热门标签

    更多
    JavaquerypythonNode开发语言requestUtil数据库Table后端算法LoggerMessageElementParser

    最新问答

    更多
    • 蜀ICP备13028337号-1 大数据知识库 https://www.saoniuhuo.com © All rights reserved
    • 本站内容来源互联网,如果侵犯您的权益请联系我们删除, 联系方式：448109455@qq.com