Python SQLite3 Tutorial for Beginners

This tutorial provides a brief introduction to SQLite3 using Python for beginners. SQLite3 is a lightweight, self-contained, open-source, and serverless relational database management system (RDBMS). It is widely used in applications that require a small and efficient database engine. SQLite3 is also the most widely deployed database engine in the world.

Installation

SQLite3 is a built-in module in Python, which means you don't need to install anything to use it. It's included in the Python standard library.

Creating a Database

To create a new database in SQLite3 using Python, you need to create a connection to the database using the sqlite3.connect() method. For example, to create a new database named mydb.db, use the following code:

import sqlite3

# create a new database
conn = sqlite3.connect('mydb.db')

This will create a new database file named mydb.db in the current directory.

Creating a Table

Once you have created a database connection, you can create a table in it using the conn.execute() method. To create a table, you need to specify the table schema, which includes the column names and data types. For example, to create a table named users with columns id, name, and email, where id is an integer, name is a string, and email is a string, use the following code:

# create a new table
conn.execute('''CREATE TABLE users (id INTEGER, name TEXT, email TEXT)''')

This will create a new table named users with the specified columns.

##Inserting Data After creating a table, you can insert data into it using the conn.execute() method. For example, to insert a new record into the users table, use the following code:

# insert data
conn.execute('''INSERT INTO users (id, name, email) VALUES (1, 'John Smith', 'john@example.com')''')

This will insert a new record with id 1, name 'John Smith', and email 'john@example.com' into the users table.

Querying Data

To query data from a table, use the conn.execute() method with a SELECT statement. For example, to retrieve all records from the users table, use the following code:

# query data
cursor = conn.execute('''SELECT * FROM users''')
for row in cursor:
    print(row)

This will print all the records in the users table

Updating Data

To update data in a table, use the conn.execute() method with an UPDATE statement. For example, to update the name of the record with id 1 in the users table to 'Jane Doe', use the following code:

# update data
conn.execute('''UPDATE users SET name='Jane Doe' WHERE id=1''')

This will update the name of the record with id 1 to 'Jane Doe'.

Deleting Data

To delete data from a table, use the conn.execute() method with a DELETE statement. For example, to delete the record with id 1 from the users table, use the following code:

# delete data
conn.execute('''DELETE FROM users WHERE id=1''')

This will delete the record with id 1 from the users table.

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