It is a question of honesty and of realistic expectations: If you disclose to an employer that the only reason you sought to commit a minor edit to an open source project was for him to score you more highly, not because you really wanted to do it, you'll look like dishonest (of course you may prefer to conceal the real reason but that wouldn't make you less dishonest - perhaps it will only add premeditation).
As for realistic expectations, if you think that a minor edit to an OS project will score you any points, think again: OS project contributors are really a hierarchy, and only the most committed contributors really get noticed. Listing a contribution on your CV that nobody can find let alone appreciate in context unless you'll point them to the exact URL is like saying you once threw a drop of water in the ocean. As if the ocean would care!
Don't think of making a big fuss of small things. And if you won't seek to do that, don't do small things unnecessary (and not particularly if it may take you great deal of work to get them done). Become a good user (of any database), find the job you want, and leave committing to the codebase to those who really care.