db.commit() to take effect

[progman]

I was testing the python+mysql

here are my sample codes:
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import MySQLdb
from pprint import pprint
db = MySQLdb.connect(host="localhost", user="root", passwd="password",
db="database")
cursor = db.cursor()
cursor.execute('update promo set date=100")


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i was expecting the cursor.execute will update my db immediately.
it wasn't. not until i  run db.commit(), then only i see the value
changes.

it that the right way to update db?