instead of &

Question

this returns

this is not wanted behavior either, for the purpose of my application i also need this to return 1

select 
    ts_rank(
        setweight(
            to_tsvector('bed'),
            'A'
        ),
        to_tsquery('bed')
    );

how is this behavior explained? how can i get a perfect 1 with ts_rank? i can't wrap my head around this

ts_rank  
----------
0.607927

select 
    ts_rank(
        setweight(
            to_tsvector('bed sofa'),
            'A'
        ),
        to_tsquery('bed & sofa')
    );

 ts_rank  
----------
 0.991032

Im running the next query on my postgresql (9.6) select ts_rank( setweight( to_tsvector('bed'), 'A' ), to_tsquery('bed') ); i was expecting ...

select 
    ts_rank(
        setweight(
            to_tsvector('bed sofa table'),
            'A'
        ),
        to_tsquery('bed & sofa & table')
    );

You'd have to read the source for details, but experiments show that the rank exceeds 0.6 as soon as a single word matches.

 ts_rank  
----------
 0.999999

So you could simply create a function that adjusts the rank the way you want:

select 
    ts_rank(
        setweight(
            to_tsvector('bed sofa table sky'),
            'A'
        ),
        to_tsquery('bed | sofa | table'),
        0
    );

我在我的postgresql(9.6)上运行下一个查询。

 ts_rank  
----------
 0.607927

我希望得到1（单词是相同的），但我得到的是

做一个不同的查询。

结果竟然是这样的

Answer 1

但我不想要这个，我希望得到一个1，当单词相同，除了他们的数量。

另一个测试，这次有