Design and implement the tech for displaying data as selectable widget

Design Specifications

Requirements
=========
 * Widget must be a pluggable architecture where new widgets can easily be created by injecting a different SQL query and setting a threshold.

 * Widget should perform the threshold analysis

 * Widget sends final data to HTML for display

Technology
=========
https://docs.djangoproject.com/en/dev/topics/db/queries/
---------------------
https://docs.djangoproject.com/en/dev/topics/db/sql/

from django.db import connections
cursor = connections['my_db_alias'].cursor()
# Your code here...
transaction.commit_unless_managed(using='my_db_alias')

def dictfetchall(cursor):
    "Returns all rows from a cursor as a dict"
    desc = cursor.description
    return [
        dict(zip([col[0] for col in desc], row))
        for row in cursor.fetchall()
    ]

--------------------

def my_custom_sql():
    from django.db import connection, transaction
    cursor = connection.cursor()

    # Data modifying operation - commit required
    cursor.execute("UPDATE bar SET foo = 1 WHERE baz = %s", [self.baz])
    transaction.commit_unless_managed()

    # Data retrieval operation - no commit required
    cursor.execute("SELECT foo FROM bar WHERE baz = %s", [self.baz])
    row = cursor.fetchone()

    return row

----------------------

from itertools import *
from django.db import connection

def query_to_dicts(query_string, *query_args):
    """Run a simple query and produce a generator
    that returns the results as a bunch of dictionaries
    with keys for the column values selected.
    """
    cursor = connection.cursor()
    cursor.execute(query_string, query_args)
    col_names = [desc[0] for desc in cursor.description]
    while True:
        row = cursor.fetchone()
        if row is None:
            break
        row_dict = dict(izip(col_names, row))
        yield row_dict
    return

Limitations
=========

No checking is done on the SQL statement that is passed in to .raw(). Django expects that the statement will return a set of rows from the database, but does nothing to enforce that. If the query does not return rows, a (possibly cryptic) error will result.