public static List<GeocacheFilter> getAllStoredFilters() {
            return withAccessLock(() -> queryToColl(dbTableFilters, new String[]{"name", "treeconfig"},
                    null, null, null, null, new ArrayList<>(),
                    c -> GeocacheFilter.createFromConfig(c.getString(0), c.getString(1))));
        }
removes all elements with this key from database
main/src/main/java/cgeo/geocaching/storage/DataStore.java