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slowly changing dimension

/ˈsloʊ.li ˈtʃeɪn.dʒɪŋ dɪˈmɛn.ʃən/ - n.

1 [colloq.] An attribute the business called permanent in the requirements meeting and changed twice before launch.Keep. Punchy.This is the problem.

Working definition

2. A dimension whose attribute values change over time, managed by a defined policy for whether history is overwritten, versioned, or preserved.

Promoted

See also

dimension tableWhere the company keeps every adjective it has ever applied to a customer, none of them governed.
scd type 2The full audit trail of every value the business changed its mind about, kept forever, consulted never.
schema evolutionThe fossil record of the data model: every layer a column someone added and no one was ever allowed to remove.
surrogate keyA number we invented so we would stop arguing about which real-world thing it points to. The argument moved one table over.