SQL Left Join返回NULL值

Question

I have a databse with tables schedule and a table teams (as can be seen in image below) Im trying to use the homeID & awayID inside the the schedule table to do a join on the teams table....Problem is it is returning NULL

DB Layout

Schedule Table Layout

teams table layout

My Query

SELECT s.*,
  t1.teamId as homeId_teamId,
  t1.teamCode as homeId_teamCode,
  t1.teamName as homeId_teamName,
  t2.teamId as visitorId_teamId,
  t2.teamCode as visitorId_teamCode,
  t2.teamName as visitorId_teamName
FROM schedule s
  LEFT JOIN teams t1 ON s.homeId = t1.teamName
  LEFT JOIN teams t2 ON s.visitorId = t2.teamName
WHERE  gameID = '1';

Returned Result

Any idea why am I getting a NULL value for the join? What am I missing here? Any help appreciated.

Answer 1

id s should be joined to id s (not names):

SELECT s.*,
      t1.teamId as homeId_teamId,
      t1.teamCode as homeId_teamCode,
      t1.teamName as homeId_teamName,
      t2.teamId as visitorId_teamId,
      t2.teamCode as visitorId_teamCode,
      t2.teamName as visitorId_teamName
FROM schedule s LEFT JOIN
     teams t1
     ON s.homeId = t1.teamId LEFT JOIN
     teams t2
     ON s.visitorId = t2.teamId
WHERE s.gameID = 1;

gameID is an integer, so the comparison should be to a number, not a string.

I note that the tpes of homeId and visitorId don't match teams.teamId , but naming suggests that this is the right condition. If foreign keys were properly defined, then the types would have to match.