Day 44: Updating tables

Utilizing the UPDATE Statement in SQL: Modifying Data in Your Database

There may be instances where you need to modify data in your database. For example, if you want to update the price of a specific book in your bookstore, you can use the UPDATE statement in SQL.

In this context, we start with the UPDATE keyword, followed by the name of the table we want to update, which is the books table. We then use the SET keyword to specify what we want to modify, in this case, the price, and set it to 12.99. However, we don't want to change the price for all the books, so we use the WHERE clause to specify the title of the book we want to update, 'To Kill a Mockingbird'.

Updating Data with SQL

Here's how you can update the price of 'To Kill a Mockingbird' in the books table using SQL and Python:

import sqlite3

# Connect to the bookstore.db database
conn = sqlite3.connect("bookstore.db")

# Create a cursor to execute SQL commands
cursor = conn.cursor()

# Update the price of a specific book
cursor.execute("""
UPDATE books
SET price = 12.99
WHERE title = 'To Kill a Mockingbird'
""")

# Commit the changes and close the connection
conn.commit()
conn.close()

In this Python script, we connect to the bookstore.db database and create a cursor to execute SQL commands. We then use the UPDATE statement to change the price of 'To Kill a Mockingbird' in the books table. After making the changes, we commit them to the database and close the connection.

By using the UPDATE statement, we can efficiently modify data in our SQL database, enhancing our data management capabilities and improving the readability of our code.

Learn More

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