如何將Python 2.6連接到OSI PI？

Question

我正在使用pyodbc來管理我的數據庫連接。我試圖連接到OSI PI數據庫，並收到此錯誤：

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)")

與供應商交談後，我得到了這樣的響應： 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.

我的代碼我相當簡單只是試圖在這一點上連接：

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

有沒有人連接到OSI PI的Python？如果是這樣，你是怎麼做到的？如果不是，並且您仍然使用OSI數據庫中的數據，那麼最終如何訪問它？

Answer 1

我想通了，如何做到這一點。不過，我不得不改用pyodbc。相反，我用win32com來做這個。

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：

• 這需要由OSIsoft公司提供的PIOLEDB驅動器被安裝在運行該代碼的機器上。
• 這種方法的性能似乎並不可怕。我能夠用一些其他查詢撤回數十萬條記錄，並且在可接受的時間內返回

Answer 2

嘗試使用這個http://pypi.python.org/pypi/ceODBC/2.0.1