Re: All your QWERTY belong to us...
Which is why ISO 8601 exists.
A couple of points, though:
If you are storing dates in a database and sorting on them, store them as dates (or more, likely, datetimes, or datetime2s), not as string representations, then you can index on them to your heart's content without worrying about how they are represented.
If you are trying to sort anything on dates (such as filenames), and can't, for some reason, order them by date, but must put it in the filename, it is obvious to anyone with half a brain that if the filename needs to be a sorting key, then you put the largest / least variant part first, in any hierarchical structure, e.g. yyyy-MM-dd, or yyMMddHHmmss, etc.
When representing dates and times, never get MM and mm or HH and hh mixed up (i.e. don't confuse months and minutes, and NEVER user 12 hour times - in a quarter of a century I have never seen an actual requirement to represent times that way)