php - Opencart从3个表中检索数据

Question

您好，我有这个疑问:

    $sql = "SELECT email_id as name,competition_rate as rate, competition.competition_id, competition.end_date 
FROM " . DB_PREFIX . "competition_winners as competition_winners, 
     ". DB_PREFIX . "competition as competition,
    ". DB_PREFIX . "customer as customer

WHERE competition.competition_id = competition_winners.competition_id and customer.email=competition_winners.email_id";

我需要的是从表coster 中检索另一行名为comptition_rate 的行。我正在使用 opencart，如果将其显示在与显示为名称的客户电子邮件同一行中，那就太好了。它有可能吗？它怎么可能是圆顶？

P.s.稍微更改了代码，但我无法仅显示所有结果 racing_rate 或电子邮件。

Answer 1

  $sql = "SELECT email_id as name,customer.comptition_rate as newcomrate,competition_rate as rate, competition.competition_id, competition.end_date 
FROM " . DB_PREFIX . "competition_winners as competition_winners, 
     ". DB_PREFIX . "competition as competition,
    ". DB_PREFIX . "customer as customer WHERE competition.competition_id = competition_winners.competition_id and customer.email=competition_winners.email_id";

尝试使用此查询，您将获得此 newcomrate 字段的数据