Discuss how time is represented in temporal databases and compare the different time dimensions.

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Temporal data stored in a temporal database is different from the data stored in the non-temporal database in that a time period attached to the data expresses when it was valid or stored in the database. As mentioned above, conventional databases consider the data stored in them to be valid at a time instant now, they do not keep track of past or future database states. By attaching a time period to the data, it becomes possible to store different database states. In the temporal base, database time is represented as an ordered sequence of points in granularity. It is determined by the application and for particular applications, temporal database researchers used the term ‘chronon’ in state of point to describe the minimal granularity.



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