Python - Databases(Average(AVG), sqlite3 module, connect method, cursormethod, execute method, fetchall method)

Practical Programming
An Introduction to Computer Science
Using Python 3
(Pragmatic Programmers)
(Pragmatic Bookshelf)
Paul Gries (著)Jennifer Campbell (著)
Jason Montojo (著)Lynn Beighley (編集)

開発環境

• OS X Yosemite - Apple (OS)
• Emacs (CUI)、BBEdit - Bare Bones Software, Inc. (GUI) (Text Editor)
• Python 3.4 (プログラミング言語)

Practical Programming: An Introduction to Computer Science Using Python 3 (Pragmatic Programmers)(Paul Gries (著)、Jennifer Campbell (著)、Jason Montojo (著)、Lynn Beighley (編集)、Pragmatic Bookshelf)のChapter 17(Databases)、17.10(Exercises) 2-f.を解いてみる。

17.10(Exercises) 2-f.

コード(BBEdit)

sample2_f.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-

import sqlite3

connection = sqlite3.connect('census.db')
cur = connection.cursor()

cur.execute('SELECT AVG(population) FROM Capitals')
print(cur.fetchone()[0])

connection.commit()
connection.close()

入出力結果(Terminal, IPython)

$ ./sample2_f.py
630343.2307692308
$