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Ad Hoc Query

Answer targeted operational questions with safe, read-only queries.

Intent

Safely answer a focused question with a read-only query and a documented result.

When to use

  • You need a quick answer without building a full pipeline.
  • An incident or audit requires immediate validation.
  • You are exploring a dataset to define future automation.

Core mechanics

  • Define the question and the authoritative data source.
  • Use read-only access with filters and limits.
  • Record the query, assumptions, and output snapshot.

Implementation checklist

  1. State the question, scope, and time window.
  2. Confirm the source system and schema definitions.
  3. Write a read-only query with filters and limits.
  4. Capture the output with timestamps.
  5. Document assumptions and caveats.

Failure modes and mitigations

  • Misread schema or business rules -> confirm definitions before interpreting results.
  • Heavy query on production -> use replicas or strict limits.
  • Stale data -> record extract time and refresh expectations.

Observability and validation

  • Query duration, row count, and source timestamp.
  • Filters applied and any excluded records.

Artifacts

  • Saved query text or script.
  • Exported results (CSV or report).
  • Summary note with findings.
Seen in production

Seen in production as

Atlas project

SQL

Centralize operational queries for reporting, audits, and data movement workflows. It ingests Database tables (Aeries and related systems) …

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