Neo4j中的多级全文搜索

Question

当我在索引上调用db.index.fulltext.queryNodes()时，我可以对结果运行另一个全文查询吗？我需要搜索我的数据库中的7-8个不同的属性跨越不同的标签与每个属性的不同搜索参数。我该怎么做呢？如果我使用reduce()函数或apoc.coll.intersection并尝试获得一个交集，例如...

CALL db.index.fulltext.queryNodes("first_name", "manas~") 
YIELD node as first_names
WITH collect(first_names) as first_name_list
CALL db.index.fulltext.queryNodes("aliases", "boncha~") 
YIELD node as aliases
WITH collect(aliases) as alias_list,first_name_list
RETURN apoc.coll.intersection(first_name_list, alias_list) AS output
LIMIT 5

这不会导致内存膨胀吗？

Answer 1

如果使用Neo4j 4.1+，最好使用subqueries：

CALL {
    CALL db.index.fulltext.queryNodes("first_name", "manas~") 
    YIELD node, score
    RETURN node, score

    UNION ALL
    CALL db.index.fulltext.queryNodes("aliases", "boncha~") 
    YIELD node, score
    RETURN node, score
}
RETURN node, sum(score) AS totalScore
ORDER BY totalScore DESC

对于交叉点，您可以计算每个节点有多少个匹配，因此如果它们在两个查询中匹配，则将计数为2：

CALL {
    CALL db.index.fulltext.queryNodes("first_name", "manas~") 
    YIELD node, score
    RETURN node, score

    UNION ALL
    CALL db.index.fulltext.queryNodes("aliases", "boncha~") 
    YIELD node, score
    RETURN node, score
}
WITH node, count(*) AS matches, sum(score) AS totalScore
WITH node, matches, totalScore
WHERE matches = 2
ORDER BY totalScore DESC
RETURN node, totalScore