多个表上的mysql全文

Question

我正在尝试在三个单独的表中进行全文搜索,并按相关性对结果进行排序.在我搜索答案期间,我发现我无法在多个表格中使用全文搜索.所以我为每个要搜索的列添加了单独的全文索引.现在的问题是我可以进行搜索,但我无法按照自己的意愿进行排序.

这是我的桌子

CREATE TABLE books (
 bookID int(11) NOT NULL AUTO_INCREMENT,
 title varchar(300) NOT NULL,
 authorID int(11) NOT NULL,
 FULLTEXT KEY title (title)
)

CREATE TABLE IF NOT EXISTS authors (
 authorID int(11) NOT NULL AUTO_INCREMENT,
 authorNamevarchar(200) NOT NULL,
 FULLTEXT KEY authorName(authorName)
);

CREATE TABLE IF NOT EXISTS chapters (
 chapterID int(11) NOT NULL AUTO_INCREMENT,
 bookID int(11) NOT NULL,
 content longtext NOT NULL,
 FULLTEXT KEY content (content)
);

和我的SQL查询.这就是我被困住的地方.

SELECT *, 
 MATCH(books.title) AGAINST('$q') as tscore,
 MATCH(authors.authorName) AGAINST('$q') as ascore
 MATCH(chapters.content) AGAINST('$q') as cscore
FROM books 
LEFT JOIN authors ON books.authorID = authors.authorID 
LEFT JOIN chapters ON books.bookID = chapters.bookID 
WHERE 
 MATCH(books.title) AGAINST('$q')
 OR MATCH(authors.authorName) AGAINST('$q')
 OR MATCH(chapters.content) AGAINST('$q')
ORDER BY ???? DESC

现在有了这个查询,我可以按标题,作者或内容进行排序.我想要做的是,将所有三列的相关性放在一起,然后按顺序排列结果.

并且,是的我知道其他搜索引擎,如lucene或sphinx,但我现在不打算使用它们.

提前致谢.

Answer 1

您应该能够在ORDER BY子句中添加tscore,ascore和cscore值.

试试这个:

SELECT *, 
 MATCH(books.title) AGAINST('$q') as tscore,
 MATCH(authors.authorName) AGAINST('$q') as ascore,
 MATCH(chapters.content) AGAINST('$q') as cscore
FROM books 
LEFT JOIN authors ON books.authorID = authors.authorID 
LEFT JOIN chapters ON books.bookID = chapters.bookID 
WHERE 
 MATCH(books.title) AGAINST('$q')
 OR MATCH(authors.authorName) AGAINST('$q')
 OR MATCH(chapters.content) AGAINST('$q')
ORDER BY (tscore + ascore + cscore) DESC

Answer 2

@Ike Walker 的解决方案很棒，但是在我的情况下，我想将一对多的结果汇总到每个搜索结果的一行中。在@Ike Walker 的解决方案中，我是如何完成工作的：

架构：

T1: Articles
T2: Comments (many comments to one article)

索引：

ALTER TABLE articles ADD FULLTEXT title_index (title)
ALTER TABLE articles ADD FULLTEXT body_index (body)
ALTER TABLE comments ADD FULLTEXT comment_index (comment)

查询语句：

SELECT 
    articles.title, 
    SUM(MATCH(articles.title) AGAINST('$q') + 
    MATCH(articles.body) AGAINST('$q') + 
    MATCH(comments.comment) AGAINST('$q')) as relevance 
FROM 
    articles 
LEFT JOIN 
    comments ON articles.id = comments.article_id 
WHERE 
    MATCH(articles.title) AGAINST('$q') 
    OR MATCH(articles.body) AGAINST('$q') 
    OR MATCH(comments.comment) AGAINST('$q') 
GROUP BY 
    articles.id 
ORDER BY 
    relevance DESC

注意：如果您想为每个字段添加权重，您可以执行类似的操作。

SUM((MATCH(articles.title) AGAINST('$q')*3) + 
        (MATCH(articles.body) AGAINST('$q')*2) + 
        MATCH(comments.comment) AGAINST('$q')) as relevance 

在这种情况下，标题将是评论中匹配值的 3 倍，正文是 2 倍。