core/DB.php
public static function modifyField(string $tbname, string $field, array $options = [])
    {
        return self::engine()->modifyField($tbname, $field, $options);
    }
public static function modifyField(string $tbname, string $field, array $options = [])
    {
        return self::engine()->modifyField($tbname, $field, $options);
    }
修改字段
@param string $tbname
@param string $field
@param array $options
@return int
@throws MysqlException