i've been a huge AskSam fan for well over a decade, It's a free-form database that allows you to define fields (if you wish to); access undefined fields (if you wish to); establish relational conections with other database files (iywt); search using Boolean (IF, OR, AND, NOT) or proximity considerations (iywt) and output whatever portion of the file you wish to. It does all this quickly, has extremely compact files, and has the great virtue of not requiring that everything you enter have the same number of fields.I'm talking mainly about the old DOS version--the Windows version, while it has some slick features, isn't nearly as versatile (IMO), and takes up a good deal more space.
Consider DigiTrad. AskSam permits a search by several defined fields (filename, keywords, tunefile)as well as permitting a full text search (with wildcards) for any word, words or phrases in the file. It lets me include songs with no tune, one tune or several tunes; is capable of linking to a program that plays the tunes and stores all this in a file that's smaller than the text files of the songs themselves (this may not seem important until you try to download it). And you can easily export data to spreadsheets or other databases (though I can't see why you'd want to).