Connecting to Database

Before we can interact with an SQLite database, we first need to establish a connection to it or create it if it doesn’t already exist. Only after connecting to the database can we start creating tables and executing other queries. Here are the detailed steps you need to follow to start working with the database:

1. Import the Library

We start by importing the sqlite3 library, which allows us to work with SQLite databases in Python.

2. Create a Connection to the DataBase

Next, we connect to the database using the command sqlite3.connect('my_database.db'). Here, 'my_database.db' is the name of the database we want to connect to. If this database doesn’t already exist, it will be created automatically.

This command creates a database file on your computer (if it doesn’t already exist) and establishes a connection to it.

3. Create a Cursor

In order to execute SQL queries, we need a cursor. A cursor is an object that allows us to send queries to the database. It helps manage the execution of SQL operations.

Now, we have a connection to the database, and we are ready to create tables, insert data, and perform other operations on the database.


              123456789
            
# Import the sqlite3 library
import sqlite3

# Create a new database (or connect to an existing one)
conn = sqlite3.connect('my_database.db')
# Create a cursor
cursor = conn.cursor()

print('We have successfully connected to the database.')

After running the code, you will have access to the "my_database.db" database and a ready-to-use cursor for executing SQL queries.

1. What happens if the database file does not exist when you try to connect to it using the command below?

2. What is the role of a cursor when working with a database?

Tudo estava claro?

Obrigado pelo seu feedback!

Seção 1. Capítulo 3