Database Administrator how-to

How to Tune a Slow Query

Small changes can make big performance gains.

Updated By the Career Education Institute Curriculum Team
Quick answer

Small changes can make big performance gains. In short: find; review; look, then complete the remaining steps below.

Step by step

  1. Find the slow query in monitoring tools.

  2. Review its execution plan.

  3. Look for table scans and missing indexes.

  4. Test an index or query rewrite.

  5. Measure performance before and after.

  6. Deploy the change through change control.

Safety reminders for database administrators

  • Follow least privilege and protect credentials
  • Use change control for production changes
  • Encrypt sensitive data
  • Keep tested backups and recovery plans

Database · SQL · Index · Backup · Restore · RPO: see the full database administrator glossary.

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