Oracle Database Upgrade from 12c to 19c

Project Overview:
This project involved upgrading an enterprise Oracle database from 12c to 19c to maintain vendor support, improve stability, and reduce operational risk. The upgrade was executed in close collaboration with business analysts and database subject matter experts and was fully validated in a test environment prior to production deployment. A detailed run book was created and followed to ensure a smooth production rollout with no issues and no outage during business hours.

Objectives

1. Upgrade Oracle Database from 12c to 19c within vendor-supported timelines.
2. Ensure zero data loss and preserve database integrity.
3. Validate all changes in a test environment prior to production.
4. Maintain uninterrupted business operations during normal working hours.
5. Create a clear, repeatable run book for execution and rollback.
6. Coordinate effectively across technical and business stakeholders.

Background

The organization was operating on Oracle 12c, which was nearing end of support. Continuing on an unsupported version increased security, compliance, and operational risks. Oracle 19c was selected as a long-term support release to provide stability and extended vendor support.

Problem

The Oracle 12c environment supported critical business applications, requiring a carefully planned upgrade to avoid disruption. Risks included deprecated features, behavior changes, and integration failures. The upgrade also needed to be thoroughly tested, documented, and aligned with business processes to ensure confidence from both technical and non-technical stakeholders.

Features

1. Cross-Functional Collaboration

   • Partnered closely with business analysts and database experts throughout planning, testing, and execution.
   • Ensured technical decisions aligned with business requirements and operational constraints.

2. Test Environment Validation

   • Performed a full end-to-end upgrade in a test environment prior to production.
   • Validated application functionality, integrations, and reporting against Oracle 19c.
   • Identified and remediated issues before production deployment.

3. Run Book Development

   • Co-authored a detailed upgrade run book with a business analyst.
   • Documented pre-checks, execution steps, validation criteria, and rollback procedures.
   • Used the run book to drive consistent execution across environments.

4. Pre-Upgrade Assessment & Remediation

   • Ran Oracle pre-upgrade checks to identify blockers and deprecated features.
   • Remediated incompatible parameters, schemas, and database objects.
   • Ensured all findings were resolved and revalidated in test.

5. Controlled Upgrade Execution

   • Executed the upgrade using Oracle-supported tools and methodologies.
   • Coordinated timing to avoid any outage during business hours.
   • Closely monitored logs and system health during execution.

6. Post-Upgrade Validation

   • Confirmed data integrity, object validity, and application functionality.
   • Verified performance, backups, and monitoring post-upgrade.
   • Ensured operational readiness before formally closing the change.

Technology Stack

• Database: Oracle Database 12c → Oracle Database 19c
• Upgrade Tools: Oracle Pre-Upgrade Tool, DBUA / manual upgrade scripts
• Operating System: Linux
• Collaboration & Documentation: Test validation plans, run books, stakeholder sign-off

Outcome

The Oracle database upgrade from 12c to 19c was successfully validated in a test environment and then deployed to production with no issues and no outage during business hours. All applications and integrations continued to operate as expected, and data integrity was fully preserved. The collaboratively developed run book and test validation process improved stakeholder confidence and established a repeatable, low-risk approach for future database upgrades.