Looks like a tweak of the date format.
This appears to be a 1 time thing, right? If so, you have 2 choices:
PHP. Write up a quick loop that reads the 877 records, does some string tricks and then reupdates the record. Not the fastest from a code execution standpoint, but should be pretty easy to whip the code up.
SQL.
Of course, you should have already made a back up of the table (and its data) you're about to modify.
You'd do something like this:
UPDATE mytable SET mydate = CONTACT(SUBSTR(mydate, 5, 2), '-', SUBSTR(mydate, 3, 2), '-', SUBSTR(mydate, 0, 2)) [where clause goes here]
Untested. You might try this on a test copy before making the official change to make sure this works. Check out all the string tricks you can do in mysql: http://dev.mysql.com/doc/mysql/en/String_functions.html
