To change values for existing rows, use UPDATE. In this back-to-basics session Chris will cover the ins-and-outs of doing this, including:

- How to write UPDATE
- Avoiding lost updates
- Getting the changed values
- Run UPDATE faster

Watch this Office Hours session to learn how UPDATE works.

Highlights of this session include:

00:55 - Structure of an update statement
03:00 - Record-based updated of all columns
05:55 - Update a query
07:00 - Demo of updating rows
08:00 - Demo of update blocking
09:20- Demo of record-based updates
11:30 - Demo of updating a query
16:45 - What is a lost update
19:30 - Avoiding lost updates with optimistic or pessimistic locking
21:45 - Pessimistic locking
25:45 - Optimistic locking
30:05 - Fetching updated values with the returning clause
31:10 - Demo of pessimistic locking
34:40 - Demo of optimistic locking
40:15 - Returning clause to get values from many updated rows
41:55 - How to update one table using values from another
45:55 - Update only merge
46:45 - "Update" using create-table-as-select
48:25 - dbms_redefinition.execute_update
48:50 - demo comparing performance of update methods
58:45 - Recap

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