Concept tag
#three-valued-logic
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Why does my SQL query treat NULL = NULL as neither true nor false?
Beginner question from a data analyst. Last week a report of mine undercounted customers by about four per cent. The bug was a filter like WHERE region 'KL', which I assumed would return everyone outside Kuala Lumpur. It also silently dropped every…
Started by Nur Aisyah Rahman4 replies -
Strong Kleene, weak Kleene, Łukasiewicz: what actually differs between the tables?
I've been reading about how to reason with partially evaluated expressions, where some sub-expressions haven't been computed yet or failed. That led me to three-valued logics, and now I have three sets of truth tables on my desk that look almost identical.…
Started by Pieter van Dijkhuizen4 replies