How is operation management carried out within a single database transaction?

Managing operations within a single transaction in a database is usually done using a transaction mechanism that guarantees atomicity, consistency, isolation, and durability (ACID). In Python, when working with a database through libraries such as sqlite3 or psycopg2, a transaction starts automatically or explicitly, and changes are committed with the commit command or rolled back with rollback.

Example using sqlite3:

import sqlite3
conn = sqlite3.connect('example.db')
cursor = conn.cursor()

try:
    cursor.execute("INSERT INTO users (name) VALUES ('Alice')")
    cursor.execute("INSERT INTO accounts (user_id, balance) VALUES (last_insert_rowid(), 1000)")
    conn.commit()  # commit changes
except Exception as e:
    conn.rollback()  # rollback changes on error
    print(f"Error: {e}")
finally:
    conn.close()

Thus, all operations inside the block are either applied together or not at all.