The main challenge here is that extending relational algebra ("key tuple maps to row") into time ("key tuple maps to function from time to row") essentially cross-products two different dimensions, creating a much bigger domain to process and reason about.
Once you have the theory down, you can express some pretty handy relationships.
For you functional folks, you can consider the TRA as the regular RA lifted into the time monad. Except the composition can also go cross-wise; TRA can also be considerd as the narrow timeline lifted into the relational monad. Fun times!
For example: https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.47... (This being a not fully settled / exploited area of computational science, there are plenty of alternative interpretations, too.)
The main challenge here is that extending relational algebra ("key tuple maps to row") into time ("key tuple maps to function from time to row") essentially cross-products two different dimensions, creating a much bigger domain to process and reason about.
Once you have the theory down, you can express some pretty handy relationships.
For you functional folks, you can consider the TRA as the regular RA lifted into the time monad. Except the composition can also go cross-wise; TRA can also be considerd as the narrow timeline lifted into the relational monad. Fun times!