使用Pyodbc和SQLAlchemy连接到SQL Server

Question

Here is some background on what I am trying to accomplish: My work created an application that stores information in a SQL database for each job we work on. I am trying to automate some of our workflow process using python, but I would like to have access to the information in the database.

From what I understand, to accomplish this I need to connect the database to a SQL server. I am trying to do this using SQLAlchemy and pyodbc. As part of the application I have Microsoft SQL Server 2008 R2 and SQL Server Native Client 10.0 as the driver.

The issue is I am not able to connect to the SQL server using SQLAlchemy or pyodbc using the create_engine() or connect() methods. I have tried a couple different methods below:

1) Using a DSN: I was unable to create a system or user DSN as I would get this error message Error

2) using SQLAlchemy and a hostname connection:

engine = sqlalchemy.create_engine("mssql+pyodbc://user:password@.\DT_SQLEXPR2008/C:\SQLTest\JobDB.mdf?driver=SQL+Server+Native+Client+10.0")
engine.connect()

3) using SQLAlchemy and windows authentication:

engine = sqlalchemy.create_engine('mssql+pyodbc://DT_SQLEXPR2008/C:\SQLTest\JobDB.mdf?driver=SQL+Server+Native+Client+10.0')
engine.connect()

4) Using pyodbc connect() method:

conn = pyodbc.connect('DRIVER={SQL Server Native Client 10.0};SERVER=.\DT_SQLEXPR2008;DATABASE=C:\SQLTest\JobDB.mdf;UID=user;PWD=password')

In the above I entered my windows username and password in place of "user" and "password". Here is a picture of SQL config. manager showing the existing SQL server and my user I am logged on with.

I have tried setting the server as .\\DT_SQLEXPR2008 as well as 'computername'\\DT_SQLEXPR2008

Each time I receive this error message:

InterfaceError: (pyodbc.InterfaceError) ('28000', "[28000] [Microsoft][SQL Server Native Client 10.0][SQL Server]Login failed for user 'z003vrzk'. (18456) (SQLDriverConnect); [28000] [Microsoft][SQL Server Native Client 10.0][SQL Server]Login failed for user 'z003vrzk'. (18456)") (Background on this error at: http://sqlalche.me/e/rvf5 )

Can anyone tell me how to add a database to a SQL server and read the information it contains?

Answer 1

This will be redundant for SQL users, but I have not seen this question answered using python+pyodbc.

First I needed to connect to the master database residing on the SQL server instance on my computer:

connMaster = pyodbc.connect('DRIVER={SQL Server Native Client 10.0}; 
SERVER=.\DT_SQLEXPR2008;DATABASE=master;Trusted_Connection=yes;')
cursorMaster = connMaster.cursor()

DT_SQLEXPR2008 is the SQL server instance name, master is the database name, and I'm connecting using windows authentication.

Next I need to attach the database residing in the path: C:\\Path\\To\\SQL\\JobDB.mdf:

    sql1 = "CREATE DATABASE PBJobDB"
    sql2 = "ON (Filename = '{pathMDF}'), (Filename = '{pathLDF}')".format(pathMDF = pathMDF, pathLDF = pathLDF)
    sql3 = "FOR Attach"
    sql = sql1 + " " + sql2 + " " + sql3
    print(sql)
    connMaster.autocommit = True
    cursorMaster.execute(sql)
    connMaster.autocommit = False

PathMDF and PathLDF are file path names to the master data file and log file.

If you want to connect to a database in a networked location, we will need TRACEON 1807 (haven't gotten this working yet).