Worked on improving the reliability of numeric operations in the pingcap/tidb repository, focusing on backend development and database correctness. Addressed a critical bug in the Truncate function by ensuring the unsigned flag was properly propagated from input to output, which prevents incorrect behavior when handling unsigned integers. This fix reduced the risk of edge-case errors in truncation paths and enhanced data integrity for unsigned arithmetic. The work involved end-to-end patch development using Go and SQL, demonstrating careful attention to detail in expression evaluation and numeric flag management, and contributed to the overall stability of the codebase without introducing new user-facing features.