Hi, ----- Original Message ----- From: "Sergei Golubchik" To: "Steven Roussey" Sent: Wednesday, December 10, 2003 7:44 AM Subject: Re: 4.1.1 FTS 2-level?
> Hi! > > On Dec 09, Steven Roussey wrote: > > Does Mysql 4.1.1 have the two level index system integrated into it for full > > text searches? > > What do you mean ? > Is it used to optimize searches ? No. > > Still there could be some speedup because, e.g, MyISAM will use binary > search in the key pages instead of linear one, etc. > > Regards, > Sergei You're right. Wow! I assume you were comparing it to 4.0.x, not 4.1.0. Once the data rows are cached, the index search in boolean mode seems to be about *7 times* faster than 4.0. :-) 2 test searches on the same data went from 48s -> 7 and 35 -> 5. Nice! Of course, if the data rows have to be read from disk, the full-text code can do nothing to improve those reads. :*( So are these faster index searches only the result of binary vs linear search? (I don't know the exact difference, but binary sounds good. ;-)) The actual full-text code itself is NOT any more optimized than 4.0? Are the 2-level indexes solely for FTS to use, or can MyISAM use them in general for any indexes? Just wondering, since you said "Is it used to optimize searches? No." Which sounds like it's being used for *storage*, just not the word count statistics for optimization, etc. And my index file was reduced from 1.74G in 4.0 to 1.59G, so I thought maybe this is where some space was saved. BTW, would (re)building the index be slower with 4.1 for any reason? I thought maybe it was, but I'd have to try again to be sure. Matt -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
