simple web app which serves as a link shortener, which can give another link based on chance

gambleLink.py

from flask import Flask, g, request, redirect
from datetime import datetime
import sqlite3
import random

app = Flask(__name__)

DATABASE = "short.db"
SECRET = "UltraSecretCode32904235235"

def get_db():
	db = getattr(g, '_database', None)
	if db is None:
		db = g._database = sqlite3.connect(DATABASE)
		cur = db.cursor()
		cur.execute(create_table_sql)
	return db

@app.teardown_appcontext
def close_connection(exception):
	db = getattr(g, '_database', None)
	if db is not None:
		db.close()

create_table_sql = """
CREATE TABLE IF NOT EXISTS links (
	id text PRIMARY KEY NOT NULL,
	link text NOT NULL,
	second_link text NOT NULL,
	chance_second REAL NOT NULL,
	submission_date text NOT NULL
);
"""

@app.route("/g/<id>")
def get_link(id):
	cur = get_db().cursor()
	cur.execute("SELECT * FROM links WHERE id=?", (id,))
	res = cur.fetchone()
	if not res:
		return "Not found!", 404
	if random.random() > res[3]:
		return redirect(res[1])
	else:
		return redirect(res[2])

@app.route("/s/<id>", methods=["POST"])
def set_link(id):
	data = request.form
	if "link" not in data or "second_link" not in data or "chance" not in data:
		return "No link, second link or chance supplied!", 403
	if "secret" not in data or data["secret"]!=SECRET:
		return "Invalid secret!", 403
	db = get_db()
	cur = db.cursor()
	try:
		cur.execute("INSERT INTO links VALUES (?,?,?,?,?)", (
			id,
			data["link"],
			data["second_link"],
			float(data["chance"]),
			datetime.now().isoformat()))
	except Exception as e:
		return str(e), 403
	db.commit()
	return "", 200

if __name__ == "__main__":
	app.run()