With a bit of delay, we would like to announce a publication of the first synthetic database including both black holes in binaries, i.e. with gravitationally bound companion stars, and those which exist as single objects. The latter might have formed from massive single stars (at least twenty times more massive than the Sun) or, more probably, as a result of binary disruptions and stellar mergers. This study is a starting point for other more in-depth analysis of black hole populations in the Milky Way and other galaxies. You can find the publication here https://ui.adsabs.harvard.edu/abs/2019ApJ...885....1W, whereas the database is publicly available here https://universeathome.pl/universe/bhdb.php.