使用 Dask pyodbc 和 SQLAlchemy 从 SQL Server 中提取数据

Question

我想用 Dask 拉一堆数据。

我正在使用

SQLAlchemy==1.3.9
dask==2.5.2
pyodbc==4.0.27

我在与脚本相同的目录中有以下文件：

odbc.ini
odbcinst.ini

我无法正确配置。我已经看到一堆 SQLAlchemy 的连接字符串，但我无法让其中任何一个工作。

此代码有效：

#!/usr/bin/env python
import pyodbc
import getpass

#odbc is the prefered method for contacting microsoft sqlserver
sql_server_cnxn_str = 'DRIVER={ODBC Driver 17 for SQL Server};' + \
                      'SERVER=XXXX;DATABASE=YYYY;' + \
                      'Trusted_Connection=yes;'
#get username
print ("Input username then hit enter: ")
name = input()
#Get password
psswd = getpass.getpass()
#Create connection using odbc
conn = pyodbc.connect(sql_server_cnxn_str)
cursor = conn.cursor()

query = "SELECT * from Foo.Testing"

cursor.execute(query)
data = cursor.fetchall()
print(data)

所以我知道连接有效。

这是我要开始工作的代码：

#!/usr/bin/env python
import pyodbc
import getpass
import dask.dataframe as dd
from dask.diagnostics import ProgressBar

#odbc is the prefered method for contacting microsoft sqlserver
sql_server_cnxn_str = 'DRIVER={ODBC Driver 17 for SQL Server};' + \
                      'SERVER=XXXX;DATABASE=YYYY;' + \
                      'Trusted_Connection=yes;'
#get username
print ("Input username then hit enter: ")
name = input()
#Get password
psswd = getpass.getpass()

#If neither divisions or npartitions is given, the memory footprint of the first few rows will be determined, and partitions of size ~256MB will be used.
data = dd.read_sql_table("Foo.Testing", sql_server_cnxn_str, index_col="Test")

我不断收到此错误：

File "src/pymssql.pyx", line 642, in pymssql.connect
sqlalchemy.exc.OperationalError: (pymssql.OperationalError) (18456, b"Login failed for user 'foobar'.DB-Lib error message 20018, severity 14:\nGeneral SQL Server error: Check messages from the SQL Server\nDB-Lib error message 20002, severity 9:\nAdaptive Server connection failed (ROEFDN819Q)\nDB-Lib error message 20002, severity 9:\nAdaptive Server connection failed (ROEFDN819Q)\n")

我尝试了许多连接字符串格式，包括： ‘mssql+pyodbc://server_name/database_name?driver=SQL Server?Trusted_Connection=yes’

"mssql+pymssql://{user}:{password}@{host}:{port}/{database}".format(user=username, password=password, host=server, database=database, port=port)

("mssql+pyodbc://%s:%s@%s/%s?driver=%s" % (username, password, server, database, driver ) )

"mssql+pyodbc://{0}:{1}@XXXX/YYYY".format(username,password)

没有任何作用。我不能以某种方式从 pyodbc 中提取正确的配置吗？非常感谢您的帮助！

Answer 1

这个怎么样？

import pypyodbc 
cnxn = pypyodbc.connect("Driver={SQL Server Native Client 11.0};"
                        "Server=Server_Name;"
                        "Database=DB_Name;"
                        "Trusted_Connection=yes;")

cursor = cnxn.cursor()
cursor.execute('SELECT * FROM Actions')

for row in cursor:
    print('row = %r' % (row,))

或者，使用登录凭据，试试这个？

pyodbc.connect("Driver = {SQL Server Native Client 11.0};"               
               "Server = Server_Name;"
               "Database = Database_Name;"
               "username = User_Name;"
               "password = User_Password;"
               "Trusted_Connection = yes;")

我以前从未使用过 Dask，但这看起来很有希望。

username = 'jesse'
password = 'DataScienceRulez'
hostname = 'localhost'
database_name = 'DSAS'
odbc_driver = 'ODBC+Driver+13+for+SQL+Server'

connection_string = 'mssql+pyodbc://{0}:{1}@{2}/{3}?driver={4}'.format(username, password, hostname, database_name, odbc_driver)

data = dd.read_sql_table('violations', connection_string, index_col='Summons Number')

资源：

https://livebook.manning.com/book/data-science-at-scale-with-python-and-dask/chapter-4/72