Knobit of Data modelling · K-624 · Skill

Recognises a reference to a versioned table by business key alone

What it means

A foreign key or join to a table with versions that names the business key and not the version, or a code resolved through today's reference data. Each row multiplies by the number of versions, or past rows change meaning when the reference data does.

How it is assessed

Flags the deficient case and passes the acceptable one. Deficient: `fact_payment.account_identifier` joined to `dim_account` on `account_identifier`: one payment becomes three; `customer_segment_code` resolved through today's `ref_customer_segment`, so a 2025 report changes after the segment boundaries are widened Acceptable: The fact references the version key valid at the event date (`account_key`); reference tables carry validity, and the fact stores the code valid at the time

Builds on

Explains history strategies and validity-period conventionsK-658 · Knowledge

Needed by

Recognises a past event judged against present dataK-715 · Skill