Using MySQL in Flask

问题:

Can someone share example codes in Flask on how to access a MySQL DB? There have been documents showing how to connect to sqlite but not on MySQL.

Thank you very much in advance

回答1:

from flask import Flask
from flask.ext.sqlalchemy import SQLAlchemy

app = Flask(__name__)
app.config['SQLALCHEMY_DATABASE_URI'] = 'mysql://username:password@server/db'
db = SQLAlchemy(app)


class User(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    username = db.Column(db.String(80), unique=True)
    email = db.Column(db.String(120), unique=True)

    def __init__(self, username, email):
        self.username = username
        self.email = email

    def __repr__(self):
        return '<User %r>' % self.username

You can google "Flask-Sqlalchemy" for more things.

回答2:

Firstly you need to install Flask-MySQL package. Using pip for example:

pip install flask-mysql

Next you need to add some configuration and initialize MySQL:

from flask import Flask
from flaskext.mysql import MySQL

app = Flask(__name__)
mysql = MySQL()
app.config['MYSQL_DATABASE_USER'] = 'root'
app.config['MYSQL_DATABASE_PASSWORD'] = 'root'
app.config['MYSQL_DATABASE_DB'] = 'EmpData'
app.config['MYSQL_DATABASE_HOST'] = 'localhost'
mysql.init_app(app)

Now you can get connection and cursor objects and execute raw queries:

conn = mysql.connect()
cursor =conn.cursor()

cursor.execute("SELECT * from User")
data = cursor.fetchone()

回答3:

Pretty simple with pymysql:

from flask import Flask, request, render_template
import pymysql

db = pymysql.connect("localhost", "username", "password", "database")

app = Flask(__name__)
api = Api(app)

@app.route('/')
def someName():
    cursor = db.cursor()
    sql = "SELECT * FROM table"
    cursor.execute(sql)
    results = cursor.fetchall()
    return render_template('index.html', results=results)

if __name__ == '__main__':
app.run(debug=True)

In your index.html file just do something like:

<div>
<% for row in results %}
      <tr>
         <td>{{ row[0] }}</td>
         <td>{{ row[1] }}</td>
         <td>{{ row[2] }}</td>
         <td>{{ row[3] }}</td>
      </tr>
{% endfor %}
</div>

回答4:

#!/usr/bin/python
from flask import Flask,jsonify,abort, make_response
import MySQLdb

app = Flask(__name__)

db = MySQLdb.connect("localhost", "root", "yourDbPassWord", "DBname")

@app.route('/api/v1.0/items', methods=['GET'])
def get_items():
    curs = db.cursor()
    try:
        curs.execute("SELECT * FROM items")
        ...

    except:
        print "Error: unable to fetch items"
    return jsonify({"desired: " response})