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And on top of that, if the database is PROPERLY DESIGNED and uses correct RELATIONAL INTEGRITY, then task 3.3.4 is impossible. For that matter, the data as presented there is impossible. So somebody is teaching you bad database design.
Specifically, propid in the PERSONS table should be a foreign key to propid in the PROPERTIES table. And so the propid of 4 in the PERSONS table would be impossible in a correctly designed and implemented database.
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An optimist sees the glass as half full.
A pessimist sees the glass as half empty.
A realist drinks it no matter how much there is.
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