What is temporality?
What does the term temporality mean? Is it the logical concept or the physical model supported by the infrastructure? Or can it just be defined by a set of rules that must be applied? Well, it does not reflect a specific model or implementation. Instead, temporality covers any solution that deals with time. Namely, each object state (data tuple) can be positioned on a timeline. Thus, each object is delimited by multiple states valid during the specified period of time. Generally speaking, relational databases can be automatically considered to be partially temporal, whereas each data change is always encapsulated by the transaction. And each transaction generates data change vectors stored in the transaction logs. So, what does it actually mean? Such a transaction log structure clearly denotes the object state history, doesn´t it? Thus, the transactional databases can produce states valid in the past. However, it is not as simple as it may seem at first glance...
