Editing Durability (database systems) (section)

=== Transaction level ===
Durability against failures that occur at transaction level, such as canceled calls and inconsistent actions that may be blocked before committing by [[Constraint (database)|constraints]] and [[Database trigger|triggers]], is guaranteed by the [[serializability]] property of the execution of transactions. The state generated by the effects of precedently committed transactions is available in main memory and, thus, is resilient, while the changes carried by non-committed transactions can be undone. In fact, thanks to serializability, they can be discerned from other transactions and, therefore, their changes are discarded.<ref name=":1" /> In addition, it is relevant to consider that in-place changes, which overwrite old values without keeping any kind of history are discouraged.<ref name=":0" /> There exist multiple approaches that keep track of the history of changes, such as [[Timestamp-based concurrency control|timestamp]]-based solutions<ref>{{Cite journal |last=Svobodova |first=L. |date=1980 |title=MANAGEMENT OF OBJECT HISTORIES IN THE SWALLOW REPOSITORY |url=https://dl.acm.org/doi/10.5555/889850 |journal=Mit/LCS Tr-243 |location=USA |doi=}}</ref> or [[Logging (computing)|logging]] and [[Locking (computer science)|locking]].<ref name=":0" />