Thread: really thanks,Teodor Sigaev. HOW ts2 implment that ?

really thanks for Teodor Sigaev,beat regards.

Becaue it's very importent or me these days,so I posted it again.

>> I only know that GiST is also  "Inverse Order OF Idexing",but of course
>> it is a tree NOT as lucene does

>Tsearch2 doesn't use inverted index (yet), and so it easy to update (your index
>is always full - online indexing), but it hasn't good performance on large data
>set. The limit is about 10^5 - 10^6 rows in practice.

I know the LUCENE " inverted index " is just like follows:

keyword   doc_id[frequence]   location
guangzhou 1[2]               3，6
he       2[1]               1
i         1[1]               4
live      1[2],2[1]           2，5，2
shanghai  2[1]               3

so ,before I  thought that A node In GiST tree is very like the above :

In the tree's node , it has several value for storing its's

turple_id[frequence]   location ,and that is why I thoutht the " inverted index ".

BUT now , I'm lost again ,how does Gist tree store lexem and how to find his correspoding tuples in database( including  frequence   location)?

Or to say ,how TSearch2  implement the Lucene's "inverted index" mean ?

> I know the LUCENE " inverted index " is just like follows:
>
>
>
> keyword   doc_id[frequence]   location
> guangzhou 1[2]               3，6
> he       2[1]               1
> i         1[1]               4
> live      1[2],2[1]           2，5，2
> shanghai  2[1]               3

Yes

> so ,before I  thought that A node In GiST tree is very like the above :
>
> In the tree's node , it has several value for storing its's
>
> turple_id[frequence]   location ,and that is why I thoutht the "
> BUT now , I'm lost again ,how does Gist tree store lexem and how to find
> his correspoding tuples in database( including  frequence   location)?

Tsearch2 use "direct" index: each leaf tuple in tree represent document,
internal tuples represents union of documents.


--
Teodor Sigaev                                   E-mail: teodor@sigaev.ru
                                                    WWW: http://www.sigaev.ru/