D-Net

        sql = "SELECT coalesce(ds.source, vs.source) as source, coalesce(ds.repository_id, vs.repository_id) as repository_id, coalesce(ds.result_id, vs.result_id) as result_id, coalesce(ds.date, vs.date) as date, coalesce(ds.count, 0) as downloads, coalesce(vs.count, 0) as views, coalesce(ds.openaire, 0) as openaire_downloads, coalesce(vs.openaire, 0) as openaire_views INTO usage_stats FROM downloads_stats AS ds FULL OUTER JOIN views_stats AS vs ON ds.source=vs.source AND ds.repository_id=vs.repository_id AND ds.result_id=vs.result_id AND ds.date=vs.date;";

        stmt.executeUpdate(sql);

        sql = "CREATE INDEX usage_stats_source ON usage_stats USING btree(source);";

        stmt.executeUpdate(sql);

        sql = "CREATE INDEX usage_stats_repository_id ON usage_stats USING btree(repository_id);";

        stmt.executeUpdate(sql);

        sql = "CREATE INDEX usage_stats_result_id ON usage_stats USING btree(result_id);";

        stmt.executeUpdate(sql);

        sql = "CREATE INDEX usage_stats_date ON usage_stats USING btree(date);";

        stmt.executeUpdate(sql);