Note that indexes can only have a limited width (300 bytes or so , I believe).

Because of this, it makes sense to do a reverse of only the last N characters and limit the length of the search text to match. If your strings have varying lengths between 3 and 250 characters and your search strings are strict enough with 12 characters, add a few extra and use the reverse of the rightmost 16 characters to put the index on and truncate the search string to 16 characters as well.

This saves you a ton of otherwise unneeded duplicate data and keeps the number of page reads to a minimum.