This Spring Boot project facilitates seamless data migration from an old MySQL-based application to a new PostgreSQL-based application.

Due to significant changes in data models and business logic between the old and new systems, a simple dump-and-restore was not possible. This migration tool ensures that legacy data is transferred accurately and intelligently into the new system, enabling all APIs in the new application to work smoothly with the migrated data.

The migration process is split into two key API endpoints:

• Creates all required default entries (e.g., system settings, roles, or master data) in the new PostgreSQL database.
• Ensures the destination schema has all necessary base configurations before importing data.

• Extracts data from the legacy MySQL database.
• Transforms it according to the new data model and business rules.
• Inserts it into the new PostgreSQL structure in a format compatible with the new application logic.

After running the migration:

• The new system is fully populated with consistent, compatible data.
• All APIs in the new application behave as if the data was natively created in the new system.

• Spring Boot
• Spring Data JPA
• MySQL (source)
• PostgreSQL (target)
• Model mappers / transformers

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