如何将Python 2.6连接到OSI PI？

Question

我正在使用pyodbc来管理我的数据库连接。我试图连接到OSI PI数据库，并收到此错误：

pyodbc.Error: ('IM002', "[IM002] [OSI][PI ODBC][PI]PI-API Error <pilg_getdefserverinfo> 0 (0) (SQLDriverConnectW); [01000] [Microsoft][ODBC Driver Manager] The driver doesn't support the version of ODBC behavior that the application requested (see SQLSetEnvAttr). (0)")

与供应商交谈后，我得到了这样的响应： Looks like pyodbc is written against ODBC 3.x. The OSI PI ODBC driver is using ODBC 2.0. The python ODBC driver manager will convert most ODBC 3 calls on the fly to ODBC 2 ones. Anything added to 3, however, will obviously fail. You would need to find some way to make sure that your only using 2.0 compliant ODBC calls. Currently their is not a PI ODBC driver that is compliant with ODBC 3.0.

我的代码我相当简单只是试图在这一点上连接：

import pyodbc 
constr = 'DRIVER={PI-ODBC};SERVER=myserver;UID=MY_UID' 
pyodbc.pooling=False 
conn = pyodbc.connect(constr)   # Error at this line 
conn.close() 

有没有人连接到OSI PI的Python？如果是这样，你是怎么做到的？如果不是，并且您仍然使用OSI数据库中的数据，那么最终如何访问它？

Answer 1

我想通了，如何做到这一点。不过，我不得不改用pyodbc。相反，我用win32com来做这个。

例

from win32com.client import Dispatch 

oConn = Dispatch('ADODB.Connection') 
oRS = Dispatch('ADODB.RecordSet') 

oConn.ConnectionString = "Provider=PIOLEDB;Data Source=<server>;User ID=<username>;database=<database>;Password=<password>" 
oConn.Open() 

if oConn.State == 0: 
    print "We've connected to the database." 
    db_cmd = """SELECT tag FROM pipoint WHERE tag LIKE 'TAG0001%'""" 
    oRS.ActiveConnection = oConn 
    oRS.Open(db_cmd) 
    while not oRS.EOF: 
     #print oRS.Fields.Item("tag").Value # Ability to print by a field name 
     print oRS.Fields.Item(0).Value  # Ability to print by a field location 
     oRS.MoveNext() 
    oRS.Close() 
    oRS = None 
else: 
    print "Not connected" 

if oConn.State == 0: 
    oConn.Close() 
oConn = None 

注：

• 这需要由OSIsoft公司提供的PIOLEDB驱动器被安装在运行该代码的机器上。
• 这种方法的性能似乎并不可怕。我能够用一些其他查询撤回数十万条记录，并且在可接受的时间内返回

Answer 2

尝试使用这个http://pypi.python.org/pypi/ceODBC/2.0.1