Lightroom is a database. I have written about that before. One of the key features for me was that each picture could have an infinite number of keywords associated to it. You could then search for the keywords and find the pictures wherever they were in the catalogue (database). I used the search function of the keyword list, which was very limited in functionality. But hey, it was way better than to scroll through hundreds if not thousands of pictures to find that one picture you were looking for.