Question

Fair warning: I’m a big time noob. Please handle with kid gloves.

Details:

• Python 3.2
• MySQL 5.5
• Tornado webframe installed
• pymysql installed
• Windows 7

Problem:
I’m following the Tornado documentation on connecting to a mysql database here. I only want to connect to localhost, but I’m getting the following error message:

Traceback (most recent call last):
  File "C:\Python32\DIP3\tornado-test.py", line 5, in <module>
    class Connection(localhost,re_project, user=root, password=mypassword, max_idle_time=25200):
NameError: name 'localhost' is not defined

This is the code I’m trying to run:

import tornado.ioloop
import tornado.web
import pymysql

class Connection(localhost,re_project, user=root, password=mypassword, max_idle_time=25200):
    db = database.Connection("localhost", "re_project")
    for Bogota in db.query("SELECT * FROM cities_copy"):
        print(Bogota.title)

MySQL is currently running when I execute the code, so I don’t think that should be a problem. What else could I be doing wrong?

Answer 1

Okay, I think I understand the problem. In the documentation, the line class tornado.database.Connection(host, database, user=None, password=None, max_idle_time=25200) is part of the documentation and is not meant to be copy/pasted. That describes how to do the db = database.Connection bit.

The green code sample lines should work on their own, as long as 1) the tornado.database module is imported and 2) the db = line is adjusted to pass values appropriate for your database to the Connection method.

So:

from tornado import database  # you can use "import tornado.database" here, but then
                              # you will have to use "tornado.database.Connection()"
                              # instead of "database.Connection()"

db = database.Connection("localhost", "re_project", user="root", password="mypassword")
for bogota in db.query("SELECT * FROM cities_copy"):  # I changed "bogota" to lower-case because the convention in Python is for only classes, not objects, to have upper-case names.
    print(bogota.title)

I haven’t tested this because I do not have Python 3.2 installed, so let me know if it doesn’t work and I’ll try to adjust.