{"id":1183,"date":"2023-08-06T18:40:00","date_gmt":"2023-08-06T13:10:00","guid":{"rendered":"https:\/\/geekpython.in\/?p=1183"},"modified":"2024-03-01T17:09:03","modified_gmt":"2024-03-01T11:39:03","slug":"connect-sqlite-database-with-flask-app","status":"publish","type":"post","link":"https:\/\/geekpython.in\/connect-sqlite-database-with-flask-app","title":{"rendered":"How to Create and Connect an SQLite Database with Flask App using Python"},"content":{"rendered":"\n

This article will guide you step by step in making a database using Flask-SQLAlchemy<\/strong>. It will show you how to work with an SQLite database<\/strong> in your Flask app<\/strong>, and then how to make a form on the website to collect user information and put it into the database<\/strong>.<\/p>\n\n\n\n

<\/a>Installing Flask-SQLAlchemy Lib<\/h1>\n\n\n\n

Flask-SQLAlchemy uses SQLAlchemy<\/strong>, a powerful ORM (object-relational mapping) library for Python, allowing interaction with databases using Python.<\/p>\n\n\n\n

Open the terminal window and install the library using pip<\/code> in your project environment.<\/p>\n\n\n\n

pip install Flask-SQLAlchemy<\/pre><\/div>\n\n\n\n
<\/a>Creating SQLAlchemy Instance<\/h1>\n\n\n\n
Create a database.py<\/code> file and add the following code inside the file to create an instance of SQLAlchemy.<\/p>\n\n\n\n
\"\"\" database.py file \"\"\"\nfrom flask_sqlalchemy import SQLAlchemy\n\n\"\"\" SQLAlchemy Instance \"\"\"\ndb = SQLAlchemy()<\/pre><\/div>\n\n\n\n
This instance will be used to create the database and manage database operations.<\/p>\n\n\n\n
<\/a>Creating Models<\/h1>\n\n\n\n
SQLAlchemy provides an object-oriented approach to creating database tables and columns, defining relationships, and setting constraints using Python classes.<\/p>\n\n\n\n
Models<\/strong> let you define a database table with the fields you need in your database with constraints and relationships with other tables and fields by using only Python code.<\/p>\n\n\n\n
\"\"\" models.py file\"\"\"\n\n# SQLAlchemy Instance Is Imported\nfrom database import db\n\n# Declaring Model\nclass Vehicle(db.Model):\n    __tablename__ = \"vehicle\"\n\n    id = db.Column(db.Integer, primary_key=True)\n    name = db.Column(db.String(150), unique=True, nullable=False)\n    price = db.Column(db.Integer, nullable=False)\n    created_at = db.Column(db.DateTime(timezone=True), server_default=db.func.current_timestamp())<\/pre><\/div>\n\n\n\n
Inside the models.py<\/code> file, the SQLAlchemy instance (db<\/code>) is imported to facilitate interactions with the SQLite database.<\/p>\n\n\n\n
A class named Vehicle<\/code> is declared, which inherits from db.Model<\/code>, effectively making it an SQLAlchemy model. Inside this class, the table name and structure are specified with the following details and fields:<\/p>\n\n\n\n