使用 sqlalchemy.engine.url.URL 为 mssql+pyodbc 建立连接 URL

Question

问题...

我正在尝试通过 SQLAlchemy 连接到 MSSql 服务器。这是我的伪造凭据代码（显然不是我的真实凭据）。

代码...

credentials = {
'username'  : 'SPOTTER_xyz_ACC',
'password'  : '123Goodbye2016!@#',
'host'      : 'MARYLQLT01',
'database'  : 'LRS_DUS',
'port'      : '1560'}

connect_url = sqlalchemy.engine.url.URL(
    'mssql+pyodbc',
    username=credentials['username'],
    password=credentials['password'],
    host=credentials['host'],
    port=credentials['port'],
    query=dict(service_name=credentials['database']))

engine = create_engine(connect_url)
connection=engine.connect()

这是我遇到的 .pyodbc 错误。

(pyodbc.Error) ('IM002', '[IM002] [Microsoft][ODBC Driver Manager] Data source
name not found and no default driver specified (0) (SQLDriverConnect)')

其他详细信息

但是，奇怪的是...如果建立一个 pyodbc 连接并使用 Pandas.read_sql，那么我可以无错误地获取数据。所以我不明白为什么我会收到 'pyodbc' 错误？？？？

connection=pyodbc.connect(\
                          'Driver={SQL Server}; \
                          Server=MARYLQLT01; \
                          Database=LRS_DUS; \
                          UID=SPOTTER_xyz_ACC; \
                          PWD=123Goodbye2016!@#')

stmt='select * from PD_SC_All'
df=pd.read_sql(stmt,connection)

然后我就可以看到数据框了。

那么，为什么我在尝试连接 SQLAlchemy 时得到 (pyodbc.Error)？

系统信息

Windows 7
SQLAlchemy: 1.1.11
pyodbc: 4.0.16

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Answer 1

如 SQLAlchemy documentation 中所述，对于 mssql+pyodbc 个连接

Hostname-based connections are not preferred, however are supported. The ODBC driver name must be explicitly specified:
engine = create_engine("mssql+pyodbc://scott:tiger@myhost:port/databasename?driver=SQL+Server+Native+Client+10.0")

对于

credentials = {
    'username': 'scott',
    'password': 'tiger',
    'host': 'myhost',
    'database': 'databasename',
    'port': '1560'}

你的说法

connect_url = sqlalchemy.engine.url.URL(
    'mssql+pyodbc',
    username=credentials['username'],
    password=credentials['password'],
    host=credentials['host'],
    port=credentials['port'],
    query=dict(service_name=credentials['database']))

产生 connect_url

mssql+pyodbc://scott:tiger@myhost:1560?service_name=databasename

你真正需要的是

connect_url = sqlalchemy.engine.url.URL(
    'mssql+pyodbc',
    username=credentials['username'],
    password=credentials['password'],
    host=credentials['host'],
    port=credentials['port'],
    database=credentials['database'],
    query=dict(driver='SQL+Server'))

产生

mssql+pyodbc://scott:tiger@myhost:1560/databasename?driver=SQL+Server

使用 sqlalchemy.engine.url.URL 为 mssql+pyodbc 建立连接 URL

Building a connection URL for mssql+pyodbc with sqlalchemy.engine.url.URL

python

sql-server

connection-string

sqlalchemy

pyodbc

问题...

代码...

其他详细信息

系统信息