Code reviewMediumcr-g201

Subject Missing indexLevel Mid–Senior~25 minCommon in Databases & SQL interviewsIndustries Software development, Technology

Question

Review this SQL query + schema. The `events` table has 800M rows and this dashboard query times out.

What a strong answer looks like

Separate real bugs from style. Rank issues by severity, point at the root cause rather than the symptom, and suggest a concrete fix — specific and kind.

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Code to reviewsql

1CREATE TABLE events (2  id        BIGSERIAL PRIMARY KEY,3  tenant_id BIGINT NOT NULL,4  created   TIMESTAMPTZ NOT NULL,5  level     TEXT NOT NULL,6  payload   JSONB7);8-- only the PK index exists9 10SELECT id, level, created11FROM events12WHERE tenant_id = $113  AND created >= now() - interval '24 hours'14  AND DATE(created) = CURRENT_DATE15ORDER BY created DESC16LIMIT 100;

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