Data quality

Solution

Freshness, volume (not zero, not 10×), schema, uniqueness of the grain. Everything else is extra. 400 noisy tests train people to ignore red.

Solution

Fail on grain, uniqueness, and PII contract breaks. Ticket on a soft anomaly you cannot yet explain. Write the policy down. “It depends” without a rule is a fail.

Solution

dbt for model grain you own. GE/Soda for richer expectations and non-dbt paths. A vendor when silent breakage across hundreds of tables is the incident. Start with tests; buy when misses are expensive.

Solution

Producer owns the schema and SLA. Warehouse tests are defense in depth. A contract only in dbt is how source teams ship breaking changes on Friday.

Solution

The threshold is wrong or the owner is missing. Fix or delete. A permanently red test is worse than no test — it trains the team to ship on red.

Solution

unique on the grain, not_null on keys and amounts, a row-count vs source reconciliation, and a freshness/SLA timestamp. Anomaly tools sit on top of those, they do not replace them.

Solution

Fail on grain/uniqueness/freshness that would ship a wrong number. Ticket (warn) on soft volume drift and new enum values you have not classified. If everything fails, nothing does — people --full-refresh and go home.

Solution

dbt tests: in-repo grain on models. GE: richer assertions, often in Python jobs. MC/observability: warehouse-wide drift and lineage you did not instrument. Buying MC without unique tests is a dashboard of mysteries.

Solution

You trained the org to ignore it. Fix the data, fix the threshold, or delete the check. On-call rotation should include “burn down forever-red tests.”

Solution

Producer first (schema registry, API contract, protobuf). Warehouse tests are defense in depth. If only the warehouse tests, you find out after the app shipped. Both, with an owner on the producer.

Solution

Depends on the documented lag and unpaid orders. A 2% gap with a known pending state can be a ticket; a 2% gap on “completed_at yesterday” is a fail. Write the invariant in numbers, not “looks close.”

Solution

Land in bronze/VARIANT automatically; fail or ticket before it becomes a typed gold column. Auto-promoting unknown fields is how PII appears in BI. An allow-list is a valid contract.

Solution

Duplicate keys, late CDC, NULL in the join key, and timezone edges. Fixtures should include the incident you had last quarter. A unique test on real data still has to exist.