Miscellany

          SELECT
            tmk3_trade.widet,
            tmk3_trade.context,
            tmk3_trade.price,
            tmk3_trade.time,
            MAX(tmk3_trade.time)
          FROM
            tmk3_trade
          WHERE
            tmk3_trade.station = 15221
          GROUP BY
            tmk3_trade_widget
          ORDER BY
            tmk3_trade.context,
            tmk3_trade.price
          ;