Microsoft SQL Server 2019 Performance Tuning and Management — Lesson 2: Query Plans, Statistics and Index Tuning

Learning Objectives

• Read execution plans and identify scans, estimates, joins, spills, lookups, and expensive operators
• Tune queries, indexes, statistics, parameter behavior, and plan stability with measured validation
• Validate query plans, statistics and index tuning decisions with documented requirements, test evidence, risk controls, and measurable acceptance criteria

Detailed Topics

• Read execution plans and identify scans: Read execution plans and identify scans, estimates, joins, spills, lookups, and expensive operators
• Tune queries: Tune queries, indexes, statistics, parameter behavior, and plan stability with measured validation
• Validate query plans: Validate query plans, statistics and index tuning decisions with documented requirements, test evidence, risk controls, and measurable acceptance criteria

Guided Demonstration

1. Review the requirement, users, data, dependencies, permissions, risks, and expected result.
2. Demonstrate the relevant configuration, creation, administration, analysis, migration, or development workflow step by step.
3. Capture settings, outputs, logs, screenshots, calculations, test results, and other useful evidence.
4. Compare the observed result with acceptance criteria and explain any corrective action.

Hands-On Activity

Diagnose and improve a controlled query-performance problem.

• Document assumptions, prerequisites, and the planned sequence before starting.
• Complete the activity and preserve evidence of normal, boundary, and failure behavior.
• Record issues, corrective actions, reusable notes, and the next improvement priority.

Scenario Analysis

• Identify the business or technical decision that must be made.
• Compare valid implementation approaches and their trade-offs.
• Consider security, privacy, accessibility, performance, support, and operational impact.

Troubleshooting Focus

• Separate symptoms from causes and collect evidence before applying a fix.
• Check configuration, data, permissions, dependencies, capacity, connectivity, and recent changes.
• Validate rollback, recovery, ownership, user impact, and business continuity.

Validation Checklist

• The requirement, scope, inputs, and expected outcome are clear.
• The selected design or configuration is documented and follows approved standards.
• Normal, boundary, failure, security, accessibility, and operational conditions are reviewed.
• The result is supported by evidence and the next improvement is prioritized.

Lesson Outcome

Learners can explain and apply Query Plans, Statistics and Index Tuning in a realistic scenario and validate the result with documented evidence.