Data integrity law #1 – Natural Decay – When being handled, the accuracy / integrity of a data set tends to degrade over time.
Data integrity law #2 – The Need for Curation – To prevent rule #1 from making the data unusable, the data needs to be curated.
Data integrity law #3 – The Cost of Curation – Curating data always carries a cost.
Data integrity law #4 – The Cost of Scale and Referential Complexity – The more data and the more referential integrity (ie cross-linking) the greater the costs.
Data integrity law #5 – Duplication-driven Decay – If the same data is maintained in more than one place (without automated synchronisation), the faster the decay time of law #1 and the higher the cost of law #3.
In other words, when the same fact is maintained in more than one place, integrity risk and curation cost increase unless authority, synchronisation and reconciliation rules are explicit
Data integrity law #6 – Data Minimisation (Minimum Viable Data – MVD) – To reduce costs and optimise integrity, retain only essential data, don’t duplicate it and keep cross-linking to a minimum.
The problem with law #6 is that it’s the cross-linking that often unearths the most dramatic insights.
Additional Laws
Data integrity law #7- Isolation of Analytical Workloads – Dougie Stevenson rightly suggested a seventh data integrity rule – always use data snapshots rather than production databases to work on your data for BI purposes such as building new reports
Data integrity Law #8: Data integrity is relative to purpose – No dataset is universally high quality. It is only fit or unfit for a stated purpose, decision and tolerance. This is the distinction between correct data and decision-ready data.
Data integrity Law #9: Trust cannot exceed provenance – The trust placed in data cannot exceed the evidence of where it came from, when it was observed and if/how it was transformed
Data integrity Law #10: Errors become more expensive the further they propagate – The further a defect travels from its point of creation, the harder and more expensive it becomes to detect, explain and repair
Data integrity Law #11: Reconciliation and inference cannot manufacture truth – Where sources disagree, reconciliation requires an explicit authority, precedence rule or evidence-based decision. Matching alone cannot determine truth
Data integrity Law #12: Unrepresented uncertainty becomes false certainty – If uncertainty is not explicitly represented, downstream users and systems will eventually treat uncertain data as fact
Data integrity Law #13: Automation multiplies integrity – Automation doesn’t remove data-integrity problems. It multiplies their impact and speed




2 Responses
Nice. I tend to agree.
When I do BI sorts of things, reporting, etc. I want to leave the reference data alone and use snapshots to my sort of work.
In the snapshots – I consider them to be just that – SNAPSHOTS.
Anyway, Application data structures may be be the right thing for Reporting… 😉
Great additional advice Dougie.
Especially in highly-available systems, like we tend to use, working with an offline snapshot of data is a great rule too!!