DATABASES Signal 306
Modeling State Transitions in Postgres
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Modeling state transitions as append-only rows in a separate Postgres table preserves full history while still allowing efficient queries for the current state.
Relying on a single status column discards historical data that cannot be retroactively recovered if stakeholders later require audit trails or lifecycle analytics. Adopting an append-only status table requires more complex queries to fetch the current state, but proper indexing mitigates the performance cost.
Written by elseif from the cluster below · every claim links back to a sourceThe three things worth knowing
Storing status changes as new rows in a dedicated table captures history that a single updated column inherently loses.
Querying the current status requires finding the most recent row per user, which can be done via correlated subqueries, window functions, or DISTINCT ON.
A composite index with an included status column enables Index Only Scans to maintain query performance for current status lookups.
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