This is a great added comment, sorting is almost always important, and moreso with dates, so it is good to consider.
Another thought - avoid placeholder characters that can be used for string manipulation or insertion, like ? and : (which carry meaning in SQL parameters), or {, }, \ or / which are frequently used in Pearl/PHP strings, file paths, etc.
None of these should be a real problem when following good quoting or escaping practices, but for me, the less need to escape/quote anything, the better.