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Time and Time Again: Managing Time in Relational Databases, Part 3 – Version Patterns 1 and 2

Time and Time Again: Managing Time in Relational Databases, Part 3 – Version Patterns 1 and 2

Version Pattern 1: Updating in Place

Updates in place destroy history by overwriting the previous version of the rows they update. But in most cases, this is the way tables are in fact updated. In these cases, the business does not require that the earlier states of the updated rows be available as queryable history. For this kind of data and these business requirements, the need for history is so infrequent and so nonreal-time critical, that reconstructable history is good enough.