private static String removeFirstFlag(String sql) {
        return sql.substring(0, StringUtils.lastIndexOfIgnoreCase(sql, FIRST));
    }
remove the first flag from sql.
@param sql sql from binlog
@return sql without first flag
inlong-sort/sort-flink/sort-flink-v1.13/sort-connectors/mysql-cdc/src/main/java/org/apache/inlong/sort/cdc/mysql/utils/OperationUtils.java