>The relational model is not well suited to uncertain data, as a row in a table is generally interpreted as a true proposition. For statistical data sets, analy

>The relational model is not well suited to uncertain data, as a row in a table is generally interpreted as a true proposition. For statistical data sets, analytical processing may be better served by array/tensor models (which also exhibit uniformity). An outer join is an outer product, and you have the null value. I've never seen anyone use real tensors outside of physical simulations, but then again relational databases don't use real relationships either.