MySQL 带有子表达式的 bool 全文搜索

Question

我想在 MySQL 中编写 bool 全文搜索查询。但我想按以下顺序得到结果:

完全匹配 > 包括所有单词 > 包括部分单词

(> 表示更高。)

通过以下查询，我得到了更高的精确匹配:

SELECT *, MATCH(name,description,address) 
AGAINST('>("word1 word2 word3") <(word1 word2 word3)' IN BOOLEAN MODE) 
AS score FROM samples WHERE MATCH(name,description,address) 
AGAINST('>("word1 word2 word3") <(word1 word2 word3)' IN BOOLEAN MODE) ORDER BY score DESC

通过以下查询，我得到的文档包含的所有单词都高于包含查询某些部分的单词:

SELECT *, MATCH(name,description,address) 
AGAINST('>(+word1 +word2 +word3) <(word1 word2 word3)' IN BOOLEAN MODE) 
AS score FROM samples WHERE MATCH(name,description,address) 
AGAINST('>(+word1 +word2 +word3) <(word1 word2 word3)' IN BOOLEAN MODE) ORDER BY score DESC  

但我想合并这两个查询。这是迄今为止我得到的最好的结果，但我没有得到我想要的结果。

SELECT *, MATCH(name,description,address) 
AGAINST('>("word1 word2 word3") <(>(+word1 +word2 +word3) <(word1 word2 word3))' IN BOOLEAN MODE) 
AS score FROM samples WHERE MATCH(name,description,address) 
AGAINST('>("word1 word2 word3") <(>(+word1 +word2 +word3) <(word1 word2 word3))' IN BOOLEAN MODE) 
ORDER BY score DESC

有没有办法在没有 UNION 的情况下做到这一点？

Answer 1

这行得通吗？

  SELECT *,
         MATCH (name,description,address) 
           AGAINST ('"word1 word2 word3"' IN BOOLEAN MODE) score_exact,
         MATCH (name,description,address) 
           AGAINST ('+word1 +word2 +word3' IN BOOLEAN MODE) score_all,
         MATCH (name,description,address) 
           AGAINST ('word1 word2 word3' IN BOOLEAN MODE) score_some
    FROM samples
   WHERE MATCH (name,description,address) 
           AGAINST ('word1 word2 word3' IN BOOLEAN MODE)
ORDER BY score_exact DESC, score_all DESC, score_some DESC