Developed Delta Lake Identity Columns support in Spark for the xupefei/delta repository, focusing on enabling robust identity value generation and management within ETL pipelines. Leveraged Scala, Java, and SQL to implement Identity Column SQLConf enablement, ensuring correct behavior across CTAS, REPLACE, and partitioned-table scenarios. Designed and executed a comprehensive suite of unit and integration tests to validate high watermark stability and prevent drift in identity column values. This work improved data integrity and reliability for schema evolution and migration workflows, enhancing the consistency of identity-based operations in Spark and Delta Lake environments while emphasizing thorough testing and maintainability.