Worked on the percona/percona-server repository to deliver a targeted bug fix addressing InnoDB Instant DDL column limit enforcement. Focused on correcting the column count check within the check_if_supported_inplace_alter function, the work ensured that the 1017 user column limit is properly enforced during INSTANT DDL operations. This change prevents potential data corruption or assertion failures when columns are added or dropped, thereby improving the reliability of online DDL for production environments. Utilized C++ and SQL, applying expertise in database internals, DDL operations, and testing to align the fix with release-readiness standards and provide concise regression coverage.