Flask is a popular Python web framework that makes it easy to build web applications quickly and efficiently. One common task when building a web application is to connect to a database to store and retrieve data. MySQL is a popular open-source relational database management system that is commonly used with Flask.
In this tutorial, we will cover how to connect Flask to a MySQL database using the Flask-MySQLdb extension. We will walk you through the process of installing the required packages, configuring your Flask application to connect to a MySQL database, creating a connection to the database, and displaying the data in an HTML template.
Step 1. Install the required packages: You’ll need the Flask and Flask-MySQLdb packages to connect to a MySQL database in Flask. You can install them using pip;
pip install Flask Flask-MySQLdbStep 2. Import the required packages: In your Flask application file (usually app.py), import the required packages;
from flask import Flask, render_template, request
from flask_mysqldb import MySQLStep 3. Set up the Flask app: Create a Flask app instance and configure it with your MySQL database details. Here’s an example;
app = Flask(__name__)
# MySQL configurations
app.config['MYSQL_HOST'] = 'localhost'
app.config['MYSQL_USER'] = 'root'
app.config['MYSQL_PASSWORD'] = 'password'
app.config['MYSQL_DB'] = 'mydatabase'
# Create a MySQL instance
mysql = MySQL(app)Make sure to replace the values in the app.config dictionary with your own MySQL database details.
Step 4. Create a connection to the database: In your Flask app, create a connection to the MySQL database using the mysql.connection object;
@app.route('/')
def index():
cur = mysql.connection.cursor()
cur.execute('''SELECT * FROM mytable''')
data = cur.fetchall()
cur.close()
return render_template('index.html', data=data)In this example, we’re selecting all rows from a table called mytable and returning the data to an HTML template called index.html. Make sure to replace these with your own table and template names.
<!DOCTYPE html>
<html>
<head>
<title>My App</title>
</head>
<body>
<table>
<thead>
<tr>
<th>ID</th>
<th>Name</th>
<th>Email</th>
</tr>
</thead>
<tbody>
{% for row in data %}
<tr>
<td>{{ row[0] }}</td>
<td>{{ row[1] }}</td>
<td>{{ row[2] }}</td>
</tr>
{% endfor %}
</tbody>
</table>
</body>
</html>Step 5. Run the Flask app: Finally, run the Flask app using the app.run() method;
if __name__ == '__main__':
app.run()Conclusion
Connecting Flask to a MySQL database is a common task when building web applications. In this tutorial, we covered the steps needed to connect Flask to a MySQL database using the Flask-MySQLdb extension. We walked through installing the required packages, configuring your Flask application, creating a connection to the database, and displaying the data in an HTML template.
References
- https://www.askpython.com/python-modules/flask/flask-mysql-database
- https://hevodata.com/learn/flask-mysql/