Post-Upgrade Validation Steps

Certainly! Here is a detailed and comprehensive guide on Post-Upgrade Validation Steps for SQL Server 2022. This will help ensure that your upgrade from an earlier version of SQL Server (like 2012) to SQL Server 2022 has been successful, and that your database and systems are running optimally.

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Post-Upgrade Validation Steps for SQL Server 2022

1. Introduction

Upgrading SQL Server to a newer version, such as upgrading from SQL Server 2012 to SQL Server 2022, is a complex process that involves multiple phases: planning, testing, migration, and ultimately, validation. Once the upgrade is complete, ensuring the integrity, performance, and functionality of the system is paramount. Post-upgrade validation plays a crucial role in confirming the success of the upgrade process and ensuring that there are no regressions in database performance, security, or usability.

In this guide, we will walk you through the step-by-step post-upgrade validation process to ensure your SQL Server 2022 deployment is running smoothly.

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2. Verify Database Compatibility Level

Overview:

After upgrading SQL Server, one of the first steps in post-upgrade validation is ensuring the compatibility level for all databases is correct. SQL Server databases can be set to different compatibility levels, which dictate how the database engine handles queries and other operations. By default, when you upgrade, SQL Server might retain the old compatibility level, which can sometimes cause issues or degrade performance.

Steps:

1. Check the Current Compatibility Level:
   • To check the compatibility level of a database, use the following SQL command: SELECT name, compatibility_level FROM sys.databases WHERE name = 'YourDatabase';
2. Set Compatibility Level:
   • If necessary, update the compatibility level to 160 (the default for SQL Server 2022) using: ALTER DATABASE [YourDatabase] SET COMPATIBILITY_LEVEL = 160;
3. Validate Application Compatibility:
   • After changing the compatibility level, ensure that all applications connected to the database are functioning as expected. If issues arise, it may be necessary to adjust application code or troubleshoot based on the new query plans generated by the new compatibility level.
4. Test Critical Queries:
   • Test the performance of critical queries and transactions after the compatibility level change, especially if your application relies heavily on query optimization.

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3. Perform Functional Testing

Overview:

Functional testing is vital in confirming that all system components function as they did before the upgrade. This includes testing application functionality, data integrity, and ensuring that user interfaces work correctly with the newly upgraded database.

Steps:

1. Unit Testing:
   • Execute unit tests for your stored procedures, triggers, functions, and views to ensure they behave correctly after the upgrade.
2. Application Testing:
   • Validate that applications interacting with SQL Server continue to perform as expected, focusing on database connectivity, CRUD operations, and business logic integration.
3. User Acceptance Testing (UAT):
   • Involve business users to validate that key workflows and reports are still functioning as expected. UAT helps uncover issues that may not be immediately apparent through automated testing.
4. Third-Party Integrations:
   • Verify that third-party applications (ETL tools, reporting software, etc.) continue to integrate seamlessly with the upgraded SQL Server 2022 instance.

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4. Verify Data Integrity

Overview:

Ensuring data integrity is a key post-upgrade validation task. This involves ensuring that no data corruption occurred during the upgrade, that all records are present, and that any foreign key constraints or relationships are intact.

Steps:

1. Data Validation:
   • Run SQL queries to check the count of records in key tables, ensuring that no data loss occurred during the upgrade.
   • Example: Compare record counts between the pre-upgrade backup and the restored database: SELECT COUNT(*) FROM YourTable;
2. Check Referential Integrity:
   • Validate the consistency of foreign key constraints and relationships between tables.
   • Use the following SQL to check for orphaned records or data anomalies: SELECT * FROM YourTable WHERE ForeignKeyColumn IS NULL;
3. Check for Data Corruption:
   • Run DBCC CHECKDB to validate the integrity of the database and identify any potential corruption: DBCC CHECKDB ('YourDatabase');
4. Review Logs for Errors:
   • Check SQL Server logs for any corruption or errors during the upgrade process, and address them immediately.

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5. Performance Testing and Monitoring

Overview:

Performance testing is a critical step to ensure that the upgrade process has not introduced performance regressions. It’s also an opportunity to take advantage of new performance enhancements in SQL Server 2022.

Steps:

1. Baseline Performance Metrics:
   • Compare the current performance of SQL Server 2022 with pre-upgrade performance benchmarks (e.g., CPU, memory, disk usage, query response time).
2. Query Execution Plans:
   • Examine execution plans of frequently used queries. SQL Server 2022 offers enhanced query performance features, but some queries may need to be optimized. Use SQL Server Management Studio (SSMS) to inspect and compare execution plans: SET STATISTICS XML ON; EXEC YourQuery; SET STATISTICS XML OFF;
3. Monitor Resource Utilization:
   • Use tools like SQL Profiler and Extended Events to track query performance and resource utilization over time.
   • Monitor system resources using Performance Monitor (PerfMon) to ensure the database instance is not experiencing bottlenecks.
4. Use Query Store for Performance Tracking:
   • Enable Query Store if it’s not already enabled. Query Store helps in tracking query performance over time and identifying regressions: ALTER DATABASE YourDatabase SET QUERY_STORE = ON;

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6. Security Validation

Overview:

One of the most important steps in post-upgrade validation is ensuring that your SQL Server instance is secure. SQL Server 2022 comes with several new security features, and it is crucial to ensure that all security settings are correctly configured.

Steps:

1. Review Authentication Mode:
   • Verify that the authentication mode is properly configured (Windows Authentication or Mixed Mode) and that all logins are correctly mapped: SELECT name, type_desc FROM sys.server_principals;
2. Validate User Permissions:
   • Check that user permissions and roles are intact, ensuring that no unintended privilege escalation occurred during the upgrade.
3. Encrypt Sensitive Data:
   • Verify that Transparent Data Encryption (TDE) and Always Encrypted features are correctly configured if your organization requires data encryption.
   • For example, you can verify TDE status using: SELECT * FROM sys.database_encryption_keys;
4. Audit Configuration:
   • Review your auditing setup to ensure that all necessary security events are being logged.
5. Check for Vulnerabilities:
   • Use the SQL Server Security Best Practices checklist and Advanced Threat Protection (ATP) to ensure your SQL Server instance is secure.

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7. Check SQL Server Agent Jobs

Overview:

SQL Server Agent Jobs are typically crucial for regular database maintenance, backup operations, and other automated tasks. Post-upgrade, you need to ensure that SQL Server Agent Jobs are intact and functioning as expected.

Steps:

1. Review Existing Jobs:
   • Verify that all SQL Server Agent Jobs are present and running as expected.
   • You can view jobs using: SELECT name, enabled FROM msdb.dbo.sysjobs;
2. Test Job Execution:
   • Manually trigger jobs to ensure that they execute without errors.
   • Monitor job history to confirm successful execution.
3. Reconfigure Maintenance Plans:
   • Ensure that backup plans, index maintenance, and other maintenance jobs are correctly configured for optimal performance.

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8. Verify Backups and Restore Procedures

Overview:

Post-upgrade, it’s essential to verify that the backup and restore procedures are still functioning correctly to ensure business continuity in case of any future disasters.

Steps:

1. Backup Verification:
   • Perform a full backup of the database and test the restoration process to ensure that backups are working as expected.
   • For example, to backup the database: BACKUP DATABASE YourDatabase TO DISK = 'D:\Backups\YourDatabase.bak';
2. Restore Verification:
   • Test the restore of your backup in a test environment to confirm that the data can be successfully restored from the backup.
3. Backup Retention:
   • Review the backup retention policy and ensure old backups are deleted as per your organization’s retention policy.

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9. Review System Logs

Overview:

After an upgrade, it’s essential to review the SQL Server logs for errors or warnings that may indicate underlying issues.

Steps:

1. Check SQL Server Error Log:
   • Review the SQL Server Error Log for any issues that may have occurred during or after the upgrade process.
   • Example: EXEC xp_readerrorlog;
2. Review Windows Event Logs:
   • Check the Windows Event Viewer for any critical errors related to SQL Server.
3. Look for New Warnings or Errors:
   • Pay attention to any newly appearing warnings or errors that could indicate post-upgrade problems with SQL Server.

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Post-upgrade validation is an essential process to ensure the stability, performance, security, and functionality of your SQL Server 2022 instance. By following these validation steps — including testing compatibility, data integrity, performance, security, and backup procedures — you can confirm that the upgrade has been successful and that the system is optimized for future use.

The post-upgrade process is not just about verifying that the upgrade was successful, but also ensuring that the new system is fully operational, secure, and running at peak performance. Taking a methodical approach to post-upgrade validation will provide peace of mind and allow you to take full advantage of the new features and improvements offered by SQL Server 2022.

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