无法使用多个 LEFT JOIN 提取数据

Question

我需要提取所有在特定日期进行比赛的国家/地区，table 结构是这样的：

TABLE NAME  |  FIELDS
country     | id, name  
round       | id, season_id
season      | id, competition_id
competition | id, country_id
match       | id, round_id, date

单个 match 记录具有以下组成：

id: 60856
round_id: 65
date: 2018-06-02 00:00:00

如您所见，我在 round_id 中 match 存在争议。在roundtable上有如下设计：

id: 65
season_id: 280

season表示round的容器，所以season记录有这样的结构：

id: 161
competition_id: 48

和一个 season 有一个包含所有 rounds 的 competition。 competition 记录包含 country:

id: 48
coutry_id: 2

最后 country:

id: 2
name: albania

我如何提取所有今天进行比赛的国家/地区？

这是我试过的：

$app->get('/country/get_countries/{date}', function (Request $request, Response $response, array $args)
{
    $sql = $this->db->query("SELECT * FROM country
      LEFT JOIN `match` ON round_id = round.id
      LEFT JOIN round ON season_id = season.id
      LEFT JOIN season ON competition_id = competition.id
      WHERE match.datetime = " . $args["date"] . "");

    $sql->execute();
    $countries = $sql->fetchAll();
    return $response->withJson($countries);
});

这将 return:

SQLSTATE[42S22]: Column not found: 1054 Unknown column 'round.id' in 'on clause'

更新：

  $sql = $this->db->query("SELECT * FROM country
  LEFT JOIN competition ON country_id = competition.country_id
  LEFT JOIN competition_seasons ON competition_id = competition.id
  LEFT JOIN competition_rounds ON competition_rounds.season_id = competition_seasons.id
  LEFT JOIN `match` ON match.round_id = competition_rounds.id
  WHERE match.datetime = " . $args["date"] . "");

Answer 1

SELECT * FROM country
      LEFT JOIN competition ON country.id = competition.country_id
      LEFT JOIN season ON season.competition_id= competition.id
      LEFT JOIN round ON round.season_id= season.id
      LEFT JOIN match ON match.round_id= round.id
      WHERE match.datetime = " . $args["date"] . ""

无法使用多个 LEFT JOIN 提取数据

Cannot extract data with multiple LEFT JOIN

php

sql

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