Table Access Using B* Tree is illustrated using the example of an UPDATE statement.

• If an UPDATE is performed and the primary key remains unchanged, only the contents of the table row are changed.
• If the data length changes, the positions of subsequent entries and their addresses in the position list of the leaf page in the B* tree are changed.
• If the key field changes, the UPDATE is executed as a DELETE (Table Access (DELETE) Using B* Tree) with a subsequent INSERT (Table Access (INSERT) Using B* Tree).