Sqlite and Python — return a dictionary using fetchone()?

Question

I\'m using sqlite3 in python 2.5. I\'ve created a table that looks like this:

   create table votes (
      bill text,
      senator_id text,
      vote text)
<         


        

Answer 1

I know you're not asking this, but why not just use sqlalchemy to build an orm for the database? then you can do things like,

entry = model.Session.query(model.Votes).first()
print entry.bill, entry.senator_id, entry.vote

as an added bonus your code will be easily portable to an alternative database, and connections and whatnot will be managed for free.

Answer 2

There is actually an option for this in sqlite3. Change the row_factory member of the connection object to sqlite3.Row:

conn = sqlite3.connect('db', row_factory=sqlite3.Row)

or

conn.row_factory = sqlite3.Row

This will allow you to access row elements by name--dictionary-style--or by index. This is much more efficient than creating your own work-around.

Answer 3

Sure, make yourself a DictConnection and DictCursor as explained and shown at http://trac.edgewall.org/pysqlite.org-mirror/wiki/PysqliteFactories for example.

Answer 4

I use something like this:

class SqliteRow(object):
    def __init__(self):
        self.fields = []

    def add_field(self, name, value):
        self.fields.append(name)
        setattr(self, name, value)

    def to_tuple(self):
        return tuple([getattr(self, x) for x in self.fields])

with this:

def myobject_factory(cursor, row):
    myobject= MyObject()
    for idx, col in enumerate(cursor.description):
        name, value = (col[0], row[idx])

        myobject.add_field(name, value)
    return myobject

MyObject() is a class that inherits from SqliteRow. SqliteRow class is a base class for every object that I want to have returned by a query. Every column becomes an attribute and is logged into the fields list. Function to_tuple is used to change the whole object to a form suitable for queries (simply pass the whole object and forget).

To get different class types of that function. You would need to make a factory object, that will generate objects based on the list of fields (for example: dict with { some_unique_value_made_of_fields: class} )

This way I get a simple ORM.

Answer 5

I've used this:

def get_dict(sql):
    return dict(c.execute(sql,()).fetchall())

Then you can do this:

c = conn.cursor()
d = get_dict("select user,city from vals where user like 'a%'");

Now d is a dictionary where the keys are user and the values are city. This also works for group by

Answer 6

Simple solution, initialize a cursor object:

cursor = conn.cursor(buffered = True, dictionary = True)

Another option:

cursor = conn.cursor(MySQLdb.cursors.DictCursor)

Rest of Code:

query = "SELECT * FROM table"
cursor.execute(query)
row = cursor.fetchone()

Sources: mysql.connector.cursor , MySQLdb.cursors.DictCursor