python sqlite3 - flask

Python - sqliteEueung Mulyana

http://eueung.github.io/python/sqlitePython CodeLabs | Attribution-ShareAlike CC BY-SA

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sqlite3

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Example #1

import sqlite3conn = sqlite3.connect('example.db')c = conn.cursor()#-------------------------------------c.execute('''CREATE TABLE stocks (date text, trans text, symbol text, qty real, price real)''')

c.execute("INSERT INTO stocks VALUES ('2006-01-05','BUY','RHAT',100,35.14)"#-------------------------------------for row in c.execute('SELECT * FROM stocks ORDER BY price'): print row#-------------------------------------conn.commit()conn.close()

(u'2006-01-05', u'BUY', u'RHAT', 100.0, 35.14)

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(u'2006-01-05', u'BUY', u'RHAT', 100.0, 35.14)(u'2006-01-05', u'BUY', u'RHAT', 100.0, 35.14)(u'2006-03-28', u'BUY', u'IBM', 1000.0, 45.0)(u'2006-04-06', u'SELL', u'IBM', 500.0, 53.0)(u'2006-04-05', u'BUY', u'MSFT', 1000.0, 72.0)

Example #2

import sqlite3conn = sqlite3.connect('example.db')c = conn.cursor()#-------------------------------------t = ('RHAT',)c.execute('SELECT * FROM stocks WHERE symbol=?', t)print c.fetchone()#-------------------------------------# Larger example that inserts many records at a timepurchases = [('2006-03-28', 'BUY', 'IBM', 1000, 45.00), ('2006-04-05', 'BUY', 'MSFT', 1000, 72.00), ('2006-04-06', 'SELL', 'IBM', 500, 53.00), ]c.executemany('INSERT INTO stocks VALUES (?,?,?,?,?)', purchases)#-------------------------------------for row in c.execute('SELECT * FROM stocks ORDER BY price'): print row#-------------------------------------conn.commit()conn.close()

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See SQLite Python Tutorial

import sqlite3conn = sqlite3.connect('example.db')# first, execute without c = conn.cursor()#-------------------------------------def execprint(strin): res = conn.execute(strin) for row in res: print "ID = ", row[0] print "NAME = ", row[1] print "ADDRESS = ", row[2] print "SALARY = ", row[3], "\n"#-------------------------------------conn.execute('''CREATE TABLE COMPANY (ID INT PRIMARY KEY NOT NULL, NAME TEXT NOT NULL, AGE INT NOT NULL, ADDRESS CHAR(50), SALARY REAL);''')#-------------------------------------conn.execute("INSERT INTO COMPANY (ID,NAME,AGE,ADDRESS,SALARY) VALUES (1, 'Paul', 32, 'California', 20000.00 )"conn.execute("INSERT INTO COMPANY (ID,NAME,AGE,ADDRESS,SALARY) VALUES (2, 'Allen', 25, 'Texas', 15000.00 )"conn.execute("INSERT INTO COMPANY (ID,NAME,AGE,ADDRESS,SALARY) VALUES (3, 'Teddy', 23, 'Norway', 20000.00 )"conn.execute("INSERT INTO COMPANY (ID,NAME,AGE,ADDRESS,SALARY) VALUES (4, 'Mark', 25, 'Rich-Mond ', 65000.00 )"execprint("SELECT id, name, address, salary from COMPANY")

Example #3

ID = 1...

ID = 1NAME = PaulADDRESS = CaliforniaSALARY = 25000.0

(1, u'Paul', u'California', 25000.0)(3, u'Teddy', u'Norway', 20000.0)(4, u'Mark', u'Rich-Mond ', 65000.0)Total number of rows updated : 6

conn.execute("UPDATE COMPANY set SALARY = 25000.00 where ID=1"execprint("SELECT id, name, address, salary from COMPANY where ID=1"#-------------------------------------conn.execute("DELETE from COMPANY where ID=2;")for row in conn.execute("SELECT id, name, address, salary from COMPANY;" print row#-------------------------------------print "Total number of rows updated :", conn.total_changesconn.commit()conn.close()

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Flask SQLite 3

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Example #4

import sqlite3from flask import Flask, g#------------------------------------DATABASE = 'database.db'app = Flask(__name__)app.config.from_object(__name__)#------------------------------------def init_db(): with app.app_context(): db = get_db() with app.open_resource('schema.sql', mode='r') as f: db.cursor().executescript(f.read()) db.commit()#------------------------------------def connect_db(): rv = sqlite3.connect(app.config['DATABASE']) rv.row_factory = sqlite3.Row return rv #------------------------------------def get_db(): db = getattr(g, '_database', None) if db is None: db = g._database = connect_db() return db#------------------------------------def query_db(query, args=(), one=False): cur = get_db().execute(query, args) rv = cur.fetchall() cur.close() return (rv[0] if rv else None) if one else rv

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def seed_db(): with app.app_context(): db = get_db() seedusers = [('ujang',), ('otong',),] db.executemany('INSERT INTO users (username) VALUES (?)' #db.execute("INSERT INTO users (username) VALUES ('ujang')") #db.execute("INSERT INTO users (username) VALUES ('otong')") db.commit()#------------------------------------def print_db(): with app.app_context(): for user in query_db('select * from users'): print user['username'], 'has the id', user['id']def print_db_one(the_username): with app.app_context(): user = query_db('select * from users where username = ?' if user is None: print 'No such user' else: print the_username, 'has the id', user['id']#------------------------------------def close_db(): with app.app_context(): db = getattr(g, '_database', None) if db is not None: db.close()#------------------------------------init_db()seed_db()print_db()print_db_one('otong')close_db()

Example #4

ujang has the id 1otong has the id 2otong has the id 2

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Example #5 

[{'username': u'ujang', 'id': 1}, {'username': u'otong', 'id'127.0.0.1 - - [28/Nov/2015 15:37:09] "GET / HTTP/1.1" 200 -

import sqlite3from flask import Flask, g, jsonify#------------------------------------DATABASE = 'database.db'app = Flask(__name__)app.config.from_object(__name__)#------------------------------------def init_db(): # as previously #------------------------------------def make_dicts(cur, row): return dict((cur.description[idx][0], value) for idx, value def connect_db(): rv = sqlite3.connect(app.config['DATABASE']) #rv.row_factory = sqlite3.Row rv.row_factory = make_dicts return rv #------------------------------------def get_db(): # as previously #------------------------------------def query_db(query, args=(), one=False): # as previously

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Example #5Another Possibility (cf. JSON security)

from flask import Responseimport json#------------------------------------@app.route('/')def index(): res = query_db('select * from users') return Response(json.dumps(res), mimetype='application/json'

@app.teardown_appcontextdef close_connection(exception): db = getattr(g, '_database', None) if db is not None: db.close()#------------------------------------@app.route('/')def index(): res = query_db('select * from users') print res return jsonify(results = res)#------------------------------------ if __name__ == '__main__': app.run(host='0.0.0.0',debug=True)

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Referencessqlite3 - DB-API 2.0 - Python DocumentationUsing SQLite 3 with Flask — Flask Documentation

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ENDEueung Mulyana

http://eueung.github.io/python/sqlitePython CodeLabs | Attribution-ShareAlike CC BY-SA

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