feat(db): add data-quality monitoring views (123)

Read-only monitoring layer from the 2026-07-05 data-quality audit:
- v_scraper_health: freshness + breadth per (source vendor, obs table)
- v_stock_completeness: pct of stock fields actually extracted
- v_coverage: catalog composition + reach_label completeness
- v_data_quality_alerts: actionable open-issue list (drains to empty)
This commit is contained in:
Rene Fichtmueller 2026-07-06 05:43:17 +00:00
parent 4299e24e13
commit 0a586e0384

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-- 123-data-quality-monitoring.sql
-- Data-quality monitoring layer (read-only) from the TIP data-quality audit 2026-07-05.
--
-- NON-DESTRUCTIVE: creates four SELECT-only views. No table, column, row or
-- constraint changes. Safe to apply on a live DB and idempotent (re-runnable).
--
-- v_scraper_health freshness + breadth per (source vendor, observation table)
-- v_stock_completeness % of stock fields actually extracted, per source vendor
-- v_coverage catalog composition + reach_label completeness per manufacturer
-- v_data_quality_alerts one row per OPEN data-quality issue -> the task list
-- (goal: this view returns zero rows once everything is fixed)
--
-- Freshness thresholds (calibrated against observed scraper cadence 2026-07-06):
-- fresh = newest row within 7 days
-- stale = newest row within 30 days
-- dead = newest row older than 30 days (regression: had data, then stopped)
-- Drop in reverse-dependency order so the file is fully re-runnable.
DROP VIEW IF EXISTS v_data_quality_alerts;
DROP VIEW IF EXISTS v_scraper_health;
DROP VIEW IF EXISTS v_stock_completeness;
DROP VIEW IF EXISTS v_coverage;
-- ---------------------------------------------------------------------------
-- v_scraper_health: is each scraper still delivering, and how broad is it?
-- One row per (source vendor, observation table). Separating the tables is
-- essential: e.g. ATGBICS price is fresh while ATGBICS stock is dead.
-- ---------------------------------------------------------------------------
CREATE VIEW v_scraper_health AS
WITH obs AS (
SELECT source_vendor_id, 'stock_observations'::text AS source_table,
"time", transceiver_id
FROM stock_observations
UNION ALL
SELECT source_vendor_id, 'price_observations'::text AS source_table,
"time", transceiver_id
FROM price_observations
)
SELECT v.name AS vendor,
v.slug AS vendor_slug,
o.source_table,
count(*) AS total_rows,
count(*) FILTER (WHERE o."time" >= now() - interval '30 days') AS rows_30d,
count(DISTINCT o.transceiver_id) AS distinct_transceivers,
max(o."time")::date AS last_observation,
(now()::date - max(o."time")::date) AS days_since_last,
CASE
WHEN max(o."time") >= now() - interval '7 days' THEN 'fresh'
WHEN max(o."time") >= now() - interval '30 days' THEN 'stale'
ELSE 'dead'
END AS status
FROM obs o
JOIN vendors v ON v.id = o.source_vendor_id
GROUP BY v.id, v.name, v.slug, o.source_table;
-- ---------------------------------------------------------------------------
-- v_stock_completeness: rows are being written, but are the fields populated?
-- Catches "scraper runs but extraction is a no-op" (e.g. QSFPTEK: 75k rows,
-- 0% units_sold / warehouse / delivery).
-- ---------------------------------------------------------------------------
CREATE VIEW v_stock_completeness AS
SELECT v.name AS vendor,
v.slug AS vendor_slug,
count(*) AS stock_rows,
max(s."time")::date AS last_obs,
round(100.0 * count(s.units_sold) / count(*), 1) AS pct_units_sold,
round(100.0 * count(*) FILTER (
WHERE s.warehouse_de_qty IS NOT NULL
OR s.warehouse_global_qty IS NOT NULL) / count(*), 1) AS pct_warehouse_qty,
round(100.0 * count(*) FILTER (
WHERE s.warehouse_de_delivery_date IS NOT NULL
OR s.warehouse_global_delivery_date IS NOT NULL
OR s.backorder_estimated_date IS NOT NULL) / count(*), 1) AS pct_delivery_date,
round(100.0 * count(s.lead_time_days) / count(*), 1) AS pct_lead_time
FROM stock_observations s
JOIN vendors v ON v.id = s.source_vendor_id
GROUP BY v.id, v.name, v.slug;
-- ---------------------------------------------------------------------------
-- v_coverage: catalog composition and reach_label completeness per manufacturer
-- (transceivers.vendor_id = the brand, distinct from the scraping source vendor).
-- ---------------------------------------------------------------------------
CREATE VIEW v_coverage AS
SELECT v.name AS vendor,
v.slug AS vendor_slug,
count(*) AS transceivers,
count(*) FILTER (WHERE t.product_type = 'module') AS modules,
count(*) FILTER (WHERE t.product_type IN ('dac','aoc','aec')) AS cables,
count(*) FILTER (WHERE t.reach_label IS NULL) AS reach_label_null,
round(100.0 * count(*) FILTER (WHERE t.reach_label IS NULL) / count(*), 1) AS pct_reach_null
FROM transceivers t
JOIN vendors v ON v.id = t.vendor_id
GROUP BY v.id, v.name, v.slug;
-- ---------------------------------------------------------------------------
-- v_data_quality_alerts: the actionable task list. Each rule fires only while
-- the underlying problem is open, so the view drains to empty as things get
-- fixed. severity_rank orders critical(1) > high(2) > warning(3).
-- ---------------------------------------------------------------------------
CREATE VIEW v_data_quality_alerts AS
WITH alerts AS (
-- 1) Dead scraper: had data, stopped delivering > 30 days ago.
SELECT 'critical'::text AS severity, 1 AS severity_rank,
'scraper_dead'::text AS category,
vendor || ' / ' || source_table AS entity,
format('no new rows for %s days (last %s); %s rows total',
days_since_last, last_observation, total_rows) AS detail
FROM v_scraper_health
WHERE status = 'dead'
UNION ALL
-- 2) Stale scraper: 8-30 days since last row.
SELECT 'warning', 3, 'scraper_stale',
vendor || ' / ' || source_table,
format('no new rows for %s days (last %s)', days_since_last, last_observation)
FROM v_scraper_health
WHERE status = 'stale'
UNION ALL
-- 3) Stock rows written but extraction is empty (scraper otherwise alive).
SELECT 'high', 2, 'stock_extraction_empty',
vendor || ' / stock_observations',
format('%s rows but units_sold=%s%%, warehouse=%s%%, delivery=%s%% populated',
stock_rows, pct_units_sold, pct_warehouse_qty, pct_delivery_date)
FROM v_stock_completeness
WHERE stock_rows >= 500
AND pct_units_sold = 0
AND pct_warehouse_qty = 0
AND last_obs >= now()::date - 30
UNION ALL
-- 4) Fleet-wide delivery-date / lead-time gap -> lead_time_days not derivable.
SELECT 'high', 2, 'delivery_date_gap',
'ALL stock scrapers',
format('delivery_date on %s%% of stock rows, lead_time on %s%% -> lead_time not derivable',
round(100.0 * count(*) FILTER (
WHERE warehouse_de_delivery_date IS NOT NULL
OR warehouse_global_delivery_date IS NOT NULL) / nullif(count(*),0), 2),
round(100.0 * count(lead_time_days) / nullif(count(*),0), 2))
FROM stock_observations
HAVING round(100.0 * count(*) FILTER (
WHERE warehouse_de_delivery_date IS NOT NULL
OR warehouse_global_delivery_date IS NOT NULL) / nullif(count(*),0), 2) < 5
UNION ALL
-- 5) reach_label incomplete on a sizeable catalog.
SELECT 'warning', 3, 'reach_label_incomplete',
vendor,
format('%s%% of %s transceivers have NULL reach_label', pct_reach_null, transceivers)
FROM v_coverage
WHERE transceivers >= 100 AND pct_reach_null >= 20
UNION ALL
-- 6) Future-dated news -> ingest guard candidate.
SELECT 'warning', 3, 'future_dated_news',
'news_articles',
format('%s article(s) dated in the future (max %s) — ingest guard recommended',
count(*), max(published_at)::date)
FROM news_articles
WHERE published_at > now() + interval '2 days'
HAVING count(*) > 0
)
SELECT severity, severity_rank, category, entity, detail
FROM alerts
ORDER BY severity_rank, category, entity;