Another Example of WHERE CURRENT OF Go through all Maths students and set all GPA’s under 4.0 to 4.0!
The SQL UPDATE VIEW command can be used to modify the data of a view.
To do this without failing the entire transaction, use savepoints: BEGIN; -- other operations SAVEPOINT sp1; INSERT INTO wines VALUES('Chateau Lafite 2003', '24'); -- Assume the above fails because of a unique key violation, -- so now we issue these commands: ROLLBACK TO sp1; UPDATE wines SET stock = stock 24 WHERE winename = 'Chateau Lafite 2003'; -- continue with other operations, and eventually COMMIT; If you see anything in the documentation that is not correct, does not match your experience with the particular feature or requires further clarification, please use this form to report a documentation issue.
What I love about writing SQL Tuning articles is that I very rarely end up publishing the findings I set out to achieve. We have a table containing years worth of data, most of which is static; we are updating selected rows that were recently inserted and are still volatile. For the purposes of the test, we will assume that the target table of the update is arbitrarily large, and we want to avoid things like full-scans and index rebuilds.
If Oracle bypasses my update simply because it appears to be redundant then it may be subverting my intentions by leaving rows modifiable by other sessions when I want them locked.
Of course, you could argue that Oracle should therefore simply lock the row but not update it.
” by Markus Winand is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 Unported License.