Recognises a hierarchy encoded redundantly
A recursive relationship stored as a path string or nested-set numbers. The structure is held many times over, moving one node rewrites all its descendants, and no foreign key checks the encoding. A specific form of row 3.
Can AI do this?
Not tested yet
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What it looks like in practice
Expected result: The encoding and what keeps it consistent
How it is assessed: Flags the deficient case and passes the acceptable one. Deficient: branch.path = '/1/4/17/' with no foreign key on the parts; moving branch 4 under another region rewrites every row below it, and a mistyped path loads Acceptable: parent_branch_id with a foreign key as the system of record; a path, nested set or closure table only as a derived structure with derivation and a DQ rule. A closure table has foreign keys on both columns
Also known as: Hierarchy encoded redundantly (physical model)
Related knobits
Builds on
All 40 knobits of Design the physical data model.
Source: Review checklist 06-physical, row 8; Karwin, Naive Trees; S&W 12.6; Codd 1971