仅限于相关结果-MYSQL

Question

SELECT rideid, year, model, rating, SUM(Relevance) as 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 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，它在基于相关性系统对我的结果进行排序时效果很好。 因此，当我的两个搜索条件都满足时，这些结果将首先排序。

问题在于，两个条件都不匹配（仅匹配1个条件）的结果显然会以较低的顺序显示在结果中。 我实际上想破坏这些结果，有没有一种方法可以优化此查询，以使返回的唯一结果是满足两个条件的结果？

不能将LIKE更改为=，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

我是否丢失了某些东西，或者对于同时满足两个条件的记录，您将始终获得SUM（Relevance）= 2？

Answer 3

尝试这个：

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

Answer 4

您可以仅在GROUP BY rideid之后将HAVING SUM(Relevance) = 2到外部SELECT ，因为Relevance是对匹配的条件数的计数。 （如果以后添加更多条件，则需要将2替换为更大的数字以进行匹配。）

但是，您还可以用一种更简单的方式编写整个查询：摆脱子选择和UNION ALL ，然后在WHERE cat LIKE '%$keyword%' AND cat2 LIKE '%$keyword2%' 。 子选择和UNION是使获得仅与另一个匹配的结果成为可能。