如何按日期时间对字段进行排序

I have a table that contains a datetime field type, and I want to sort it on descending
My Datetime field have like this format:
12:17:23 PM  /  Thu, May 26th, 2016

And my code is

if($stmt=$connc->query("SELECT * FROM  static_vehicle_cat ORDER BY UNIX_TIMESTAMP(edit_date_time)  DESC"))

if column type is varchar can used this code:

SELECT
    DATE_FORMAT(
        STR_TO_DATE(
            `edit_date_time`,
            '%h:%i:%s %p / %a,%b %D, %Y'
        ),
        '%Y-%m-%d %H:%i:%s'
    )
FROM
    `static_vehicle_cat` 
ORDER BY DATE_FORMAT(
        STR_TO_DATE(
            `edit_date_time`,
            '%h:%i:%s %p / %a,%b %D, %Y'
        ),
        '%Y-%m-%d %H:%i:%s'
    ) DESC

if column type is datetime.alter table add new column type varchar and copy edit_date_time column to new column. after use code

We can easily sort date time field using query Select * from storages order by last_updated desc;

Here last_updated column having date time field type