仅限于相关结果 - MYSQL

Question

选择rideid, year, model, rating, SUM(Relevance) as SearchRelevance 从（ SELECT Rideid, year, model, rating, 1 as Relevance FROM cars WHERE cat LIKE '%$keyword%' 联合所有 SELECT Rideid, year, model, rating, 1 as Relevance FROM cars WHERE cat2 LIKE '%$keyword2%') AS t GROUP BY Rideid ORDER BY SUM(Relevance) DESC ";

大家好，我在其他成员的帮助下得到了这个很棒的查询，它非常适合根据相关性系统对我的结果进行排序。这样，当我的两个搜索条件都被满足时，这些结果将首先排序。

问题在于，不符合两个条件（仅匹配 1 个条件）的结果显然会显示在结果中，但顺序较低。我真的想丢弃这些结果，有没有办法改进这个查询，以便返回的唯一结果是同时满足这两个条件的结果？

将 LIKE 更改为 = 不是一个选项，因为结果字段是 textareas，因此 mysql 需要在 textareas 中搜索关键字。

谢谢

Answer 1

    SELECT rideid, year, model, rating, SUM(Relevance) as SearchRelevance 
      FROM( 
        SELECT rideid, year, model, rating, 2 as Relevance FROM cars 
          WHERE cat LIKE '%$keyword%' AND cat2 LIKE '%$keyword2%') 
        AS t GROUP BY rideid ORDER BY SUM(Relevance) DESC

Answer 2

您可以在GROUP BY rideid 之后将HAVING SUM(Relevance) = 2 添加到外部SELECT，因为Relevance 是匹配条件的计数。 （如果您稍后添加更多条件，则需要将 2 替换为更大的数字以匹配。）

但是，您也可以用更简单的方式编写整个查询：去掉子选择和UNION ALL，只做WHERE cat LIKE '%$keyword%' AND cat2 LIKE '%$keyword2%'。子选择和UNION 的全部意义在于能够获得仅匹配其中一个的结果。

Answer 3

我是否遗漏了某些内容，或者对于同时满足这两个条件的记录，您总是会得到 SUM(Relevance)=2？

Answer 4

试试这个：

SELECT rideid, year, model, rating, SUM(Relevance) SearchRelevance
FROM( 
    SELECT rideid, year, model, rating, 1 as Relevance FROM cars 
    WHERE cat LIKE '%$keyword%' 
    UNION ALL 
    SELECT rideid, year, model, rating, 1 as Relevance FROM cars 
    WHERE cat2 LIKE '%$keyword2%'
) AS t 
HAVING SearchRelevance > 1
GROUP BY rideid 
ORDER BY SearchRelevance DESC