Access to FULLTEXT index

[MacTommy]

I created some tables that have a FULLTEXT index on some columns.
Obviously, MySQL stores these indexes somewhere?
My question is: where?!?

Or my real question is: how can I retrieve information from these indexes (like all the words they contain).

(I already asked this question a while back (thread436-1347948) but nobody answered... :-( )

 

[ingresman]

it might be in (under windows) program files/mysql server/data/<dbname>
I get a file called tablename.MYI which I assume is mysql Index, it seems to be empty i.e. all nulls but does grow as I add rows to the base table.
What are you trying to do ?

 

[MacTommy]

Thanks! You are right. That file certainly is there, but it looks rather garbled I must say ;-)
I guess it is in some efficient MySQL-internal format.

What I want to do is iterate over all the words in the index...

 

[MacTommy]

OK, friend of mine found out that there is a way to dump your MyISAM index to a text file.

Myisam index dump:
[URL unfurl="true"]http://dev.mysql.com/doc/refman/5.0/en/myisam-ftdump.html[/url]

That gives you all the words in the index, plus some numbers that are of less avail (I would say...).

 

[ingresman]

Thers is

http://forge.mysql.com/wiki/MySQL_Internals

but it gets a bit heavy going !
interesting you get stuff i only get 0

 

[ingresman]

oops, stoped the server and it flushed the file. I'll have a look at the contents

 

[ingresman]

ok !,
look at

http://forge.mysql.com/wiki/MySQL_Internals_Algorithms

and search for myisam_ftdump.
It's in my bin directory I called it like this:

myisam_ftdump fulltext_sample 0 -d

where 0 (zero) is the index number and I only have the ful text index on this table.
Output I got was:

       54            0.9886308 alert
       88            0.9775171 alert
        0            0.9775171 appears
        0            0.9775171 good
       88            0.9775171 good
       3c            0.9886308 hear
       6c            0.9886308 love
       20            0.9886308 past

You'll have to read the internals page to see what the values mean.