20.4.4.3 Update Tables

You can use the update() method to modify one or more records in a table. The update() method works by filtering a query to include only the records to be updated and then applying the operations you specify to those records.

To replace a city name in the city table, pass to the set() method the new city name. Then, pass to the where() method the city name to locate and replace. The following example replaces the city Peking with Beijing.

mysql-py> db.city.update().set("Name", "Beijing").where("Name = 'Peking'")
Query OK, 1 item affected (0.04 sec)

Use the select() method to verify the change.

mysql-py> db.city.select(["ID", "Name", "CountryCode", "District", "Info"]).where("Name = 'Beijing'")
+------+-----------+-------------+----------+-----------------------------+
| ID   | Name      | CountryCode | District | Info                        |
+------+-----------+-------------+----------+-----------------------------+
| 1891 | Beijing   | CHN         | Peking   | {"Population": 7472000}     |
+------+-----------+-------------+----------+-----------------------------+
1 row in set (0.00 sec)