Remove some part from a database field mysql : i am saving complete file path in single field now i want to split it. bellow is my current database file path.
Current field name is "video_thumb"

    ../files/thumbs/2014-Oct/1413648778-sm.jpg 

now i want to split it into 2 fields
folder path in one field 
i want to split the following to "thumb_path"

    ../files/thumbs/2014-Oct/

the file name in another field "file_name"

    1413648778-sm.jpg 


i tried this but not access

    UPDATE video_thumb
    SET video_thumb = SUBSTRING(video_thumb, 24)
    WHERE video_thumb LIKE '_:%'

any one can help me..