Knobit of Data modelling · K-605 · Skill

Recognises an entity split into clone tables by value

What it means

One entity stored as several tables with the same columns, split by a value: a year, a region, a status. Uniqueness and foreign keys cannot span them, a change to the split value means moving the row, and every question across values needs a union. The physical form of logical row 28.

How it is assessed

Flags the deficient case and passes the acceptable one. Deficient: `payment_2025`, `payment_2026`; `payment_identifier` unique in each but not across both; `payment_hold` cannot reference "a payment"; a corrected value date moves the payment between tables Acceptable: One `payment` table partitioned by `payment_value_date` in `physical_options`, keys and foreign keys unchanged. Where separate tables are unavoidable (an archive), their predicates are disjoint and written down, and uniqueness across them is a DQ rule

Builds on

Recognises one entity split by value into severalK-528 · Skill
Explains vertical and horizontal partitioning of tablesK-660 · Knowledge

Needed by

None