My October column @AllAnalytics.
We have seen that the usefulness of the relational data model (RDM) is
in its dual theoretical foundation -- first order predicate logic (FOPL)
and set theory -- the mathematics guarantees provable logical
correctness of query results regardless what meaning is assigned to the
database R-tables. But a logically correct result is not necessarily a meaningful
result. As a reader commented "If a is Salary and b is Start date, the
[Cartesian] product a*b still doesn't have a sensible meaning." It is
critical for the analyst to understand the distinction.
Read it all. (Please comment there, not here)
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