Question

I am new to python, mongodb and sql. I am working in Eclipse 3.7.1 on a Mac 10.7. I am using a pyodbc driver (and freeTDS) to connect to an mssql database. I am scripting in python 2.7. I want to query the mssql database and write it out to a mongo database.

Where I stumble is that the query output is in a python list of tuples without field names, and I am looking for a way to convert this list of tuples into a form that mongodb will import.

Current script:

    ############
    # Query mssql
    import pyodbc
    import json
    url = 'DSN=myServer;UID=myUserName;PWD=myPassword;PORT=1433;DATABASE=mydb'
    pyodbccon = pyodbc.connect(url)
    cursor = pyodbccon.cursor()

    numusersQ = "SELECT COUNT(users.userid) FROM users"; 
    cursor.execute(numusersQ); numusers = cursor.fetchall()
    nummembsQ = "SELECT COUNT(memberships.membernumber) FROM memberships"; 
    cursor.execute(nummembsQ); nummembs = cursor.fetchall()
    userclientQ = "SELECT users.userid, users.client, users.industry FROM users"
    cursor.execute(userclientQ); userclient = cursor.fetchall()

    #format key value tuples
    output = []
    for row in userclient:
        tuplenew = {'userid': row[0], 'client': row[1], 'industry': row[2], 'numusers': numusers, 'nummembs': nummembs}
        output = [output, tuplenew]


    #output to mongo
    from pymongo.connection import Connection ;
    conmongo = Connection('localhost') 
    db = conmongo.mypymongodb

    for key, value in output():
        temp = [key,value]
        mongooutput.append(temp)

    db.pymongocollection.save(mongooutput)
    cursor = db.pymongocollection.find() 

############

OUTPUT looks like:

[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[], {'numusers': [(103068, )], 'industry': 'npwild', 'client': 'cmh', 'userid': 1, 'nummembs': [(10519, )]}], {'numusers': [(103068, )], 'industry': 'npwild', 'client': 'cmh', 'userid': 2, 'nummembs': [(10519, )]}], {'numusers': [(103068, )], 'industry': 'npwild', 'client': 'cmh', 'userid': 3, 'nummembs': [(10519, )]}], {'numusers': [(103068, )], 'industry': 'npwild', 'client': 'cmh', 'userid': 5, 'nummembs': [(10519, )]}]

ERROR MESSAGE:

Traceback (most recent call last):
  File "/Users/eclipse/workspace/pymongo/pymongopkg.py", line 34, in <module>
    for key, value in output():
TypeError: 'list' object is not callable

If anyone can just suggest a function or direct me to a solution I’d be ever so greatful.

Answer 1

this is how i got it to work:

1. pyodbc to query mssql database
2. python dict and zip to convert list of tuples into key-value dictionary pairs

3. pymongo to save it as collection

   #===============================================================================
   # 1. MSSQL QUERY WITH PYODBC
   #===============================================================================
   import pyodbc
   url = 'DSN=myserver;UID=myusername;PWD=mypassword;PORT=1433;DATABASE=mydatabase;'
   pyodbccon = pyodbc.connect(url); cursor = pyodbccon.cursor()
   
   userdataQ = "SELECT users.userid, users.client, users.industry FROM users"
   cursor.execute(userdataQ); userdata = cursor.fetchall()
   
   ##===============================================================================
   ## 2. convert tuple list to key-value dictionary
   ## 3. export to mongodb
   ##===============================================================================        
   from pymongo import Connection; conmongo = Connection('localhost') 
   db = conmongo.mypymongodb #mypymongodb = dbname
   headers = ['userid','client','industry'] 
   
   for tup in userdata:
       nextdoc = dict(zip(headers, tup))
       db.usercollection.save(nextdoc)
   print "usercollection in mypymongodb updated with " + str(db.usercollection.count()) + " docs"
   

output:

> db.usercollection.find()
{ "_id" : ObjectId("4ef000000"), "industry" : "npwild", "client" : "cmh", "userid" : 1 }
{ "_id" : ObjectId("4ef000001"), "industry" : "npwild", "client" : "cmh", "userid" : 2 }
{ "_id" : ObjectId("4ef000002"), "industry" : "npwild", "client" : "cmh", "userid" : 3 }
etc.

thank you for your help!
-d