Using MySQL commands in Python

Question

I just got into SQL to do some data science and was wondering why my code was running but not affecting the MySQL database in any way. I am using pycharm and the MySQLdb module.

 import MySQLdb
 db = MySQLdb.connect(host="localhost",
                      user="root",
                      passwd="********", #Password blocked
                      db="test")
 cur = db.cursor()
 cur.execute("SELECT * FROM movies")
 cur.execute("Update movies set genre = 'action' where id = 1")
 for row in cur.fetchall() :
     print row[0], " ", row[1], " ", row[2]

My code runs and returns no errors, but when I delete the

 cur.execute("Update movies set genre = 'action' where id = 1")

line it just prints out the table the as it was before. Just for reference, here is the table:

1 Interstellar sci-fi

2 Thor: Ragnarok action

3 Thor: The Dark World action

How can I make the commands in python actually affect the table? Thank you so much for your help!

Answer 1

You have to commit changes made to the table using cur.commit()

Database does not update automatically with MySQL and Python

Answer 2

Use cur.commit() to commit the changes to the database. Also, you should close your database using cur.close() once you're finished.