通过sqlalchemy连接prestodb

Question

我想使用 SQLalchemy 接口连接到 prestodb。我是运行 prestodb==0.7.0 和 SQLalchemy== 1.4.20 并且 SQLalchemy 似乎没有内置 prestodb：

NoSuchModuleError: Can't load plugin: sqlalchemy.dialects:presto

注册 prestodb 也不太幸运：

from sqlalchemy.dialects import registry
import prestodb
from prestodb.dbapi import  Connection

registry.register('presto', 'prestodb.dbapi', 'Connection')

from sqlalchemy.engine import create_engine 
port = 8889
user = os.environ["USER"]
engine = create_engine(f'presto://{user}@presto:{port}/hive',
                       connect_args={'protocol': 'https', 'requests_kwargs': {'verify': False}}) 
db = engine.raw_connection()

# AttributeError: type object 'Connection' has no attribute 'get_dialect_cls'

有什么想法吗？

Answer 1

如果你看一下 Dialects docs you will see that Presto is a external dialect and needs to be installed separately. The Presto dialect is supported through PiHyve 并且可以使用 pip install 'pyhive[presto]' 安装。

通过sqlalchemy连接prestodb

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