How do I undo a SQL update?

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Tags

1. #began
2. #without
3. #means
4. #usually
5. #which
6. #entire
7. #doing
8. #commit
9. #since
10. #delete
11. #getting
12. #transaction
13. #every
14. #insert
15. #update
16. #restoring
17. #called
18. #backups
19. #rollback