左联接与子选择-右表列未显示

Question

I am working on a concert promoter's website and I have to retrieve the first, last and nearest future date for shows on each tour. I am attempting to do this with the following query:

SELECT tour.*, min(date) AS `startdate`, max(date) AS finaldate
  FROM tour, tour_date
  LEFT JOIN (
    SELECT tour_id, min(date) AS nextdate
      FROM tour_date 
      WHERE date>=CURDATE()
      GROUP BY tour_id
  ) AS ndtable
    ON ndtable.tour_id=tour_date.tour_id
  WHERE tour.id=tour_date.tour_id
  GROUP BY tour_date.tour_id
  ORDER BY nextdate

I am getting the left table results but the "nextdate" column is not showing.

---

EDIT: I forgot to mention that this query is only relevant for tours with shows in the future, so I was able to rearrange it like this:

 SELECT tour.*, MIN(td.date) AS startdate, MAX(td.date) AS lastdate, MIN(ntd.date) AS nextdate FROM tour JOIN tour_date AS td ON tour.id=td.tour_id JOIN tour_date AS ntd ON tour.id=ntd.tour_id WHERE ntd.date>CURDATE() GROUP BY td.tour_id ORDER BY nextdate 

which I think is a lot neater and efficient :)

Answer 1

SELECT tour.*, min(date) AS `startdate`, max(date) AS finaldate, ndtable.nextdate
  FROM tour, tour_date
  LEFT JOIN (
    SELECT tour_id, min(date) AS nextdate
      FROM tour_date 
      WHERE date>=CURDATE()
      GROUP BY tour_id
  ) AS ndtable
    ON ndtable.tour_id=tour_date.tour_id
  WHERE tour.id=tour_date.tour_id
  GROUP BY tour_date.tour_id, ndtable.nextdate
  ORDER BY nextdate