Mysql 选择空列

我编写了一个查询，它正在选择有时为空的列

$q = "SELECT g.id AS gameid,g.home_user, g.home_user2, g.away_user, g.away_user2, g.home_score, g.away_score, g.date_confirmed, g.type,
          h1.username AS home_username, h2.username AS home_username2, a1.username AS away_username2, a2.username AS away_username2
          FROM ".TBL_FOOT_GAMES." g 
          INNER JOIN ".TBL_USERS." h1 ON h1.id = g.home_user
          INNER JOIN ".TBL_USERS." h2 ON h2.id = g.home_user2
          INNER JOIN ".TBL_USERS." a1 ON a1.id = g.away_user
          INNER JOIN ".TBL_USERS." a2 ON a2.id = g.away_user2
          WHERE g.status = '$status'
          ORDER BY g.date_confirmed DESC LIMIT 25";

柱子

家庭用户2和外出用户2

有时可以为空。显然，这似乎阻止了查询显示任何返回的数据。 当我从查询中删除这些列时，我得到了一个返回。 包含它们并不是抛出错误，只是简单地不选择任何行

如何解决这个问题？

您需要在这些列上使用内部联接，而不是内部联接

$q = "SELECT g.id AS gameid,g.home_user, g.home_user2, g.away_user, g.away_user2, g.home_score, g.away_score, g.date_confirmed, g.type,
          h1.username AS home_username, h2.username AS home_username2, a1.username AS away_username2, a2.username AS away_username2
          FROM ".TBL_FOOT_GAMES." g 
          INNER JOIN ".TBL_USERS." h1 ON h1.id = g.home_user
          LEFT JOIN ".TBL_USERS." h2 ON h2.id = g.home_user2
          INNER JOIN ".TBL_USERS." a1 ON a1.id = g.away_user
          LEFT JOIN ".TBL_USERS." a2 ON a2.id = g.away_user2
          WHERE g.status = '$status'
          ORDER BY g.date_confirmed DESC LIMIT 25";

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啊，我终于可以使用左连接了！干杯，巴德：）