archerbyron / acid Goto Github PK

try:
    cursor.execute('BEGIN TRANSACTION')

    cursor.execute('SELECT balance FROM accounts WHERE id = ?', (account_id,))
    current_balance = cursor.fetchone()[0]

    new_balance = current_balance + amount
    cursor.execute('UPDATE accounts SET balance = ? WHERE id = ?', (new_balance, account_id))

    conn.commit()
except Exception as e:
    conn.rollback()
    print(f"Transaction failed: {e}")
finally:
    conn.close()

# Account ID and amount to update balance
account_id = 123
update_amount = 200

# Update balance
update_balance(account_id, update_amount)

# Check consistency
conn = sqlite3.connect('bank.db')
cursor = conn.cursor()
cursor.execute('SELECT balance FROM accounts WHERE id = ?', (account_id,))
updated_balance = cursor.fetchone()[0]
conn.close()

# Check consistency
if updated_balance == original_balance + update_amount:
    print("Consistency maintained")
else:
    print("Consistency violated")