php - “未知表”，尽管它确实存在

Question

$query = mysql_query("SELECT company.*, factory.*
                      FROM company
                      FULL JOIN factory
                      ON company.n_id = factory.n_id
                      WHERE company.n_id = '$n_id' AND factory.n_id = '$n_id'") or die(mysql_error());

在上面你可以看到我的查询。它给我未知表'公司'错误，但公司表100%存在。我错过了什么？

编辑:当我使用右连接或左连接而不是完全连接时，它可以工作......但我需要完全连接。天哪，我会开枪射杀某人。

Answer 1

MySQL 中没有 FULL OUTER JOIN - 请参阅 this link for how to get the functionality .

$query = mysql_query("     SELECT * FROM COMPANY c
                       LEFT JOIN FACTORY f ON f.n_id = c.n_id
                      UNION ALL
                          SELECT * FROM COMPANY c
                      RIGHT JOIN FACTORY f ON f.n_id = c.n_id
                           WHERE c.? IS NULL
                             AND c.n_id = mysql_real_escape_string($n_id)
                             AND f.n_id = mysql_real_escape_string($n_id)") or die(mysql_error());

您需要将 ? 更新为 COMPANY 表中的列名称，而不是 n_id。