List:Cluster« Previous MessageNext Message »
From:Jeremy Zawodny Date:July 14 2004 6:35pm
Subject:Re: difficulty with indexes
View as plain text  
On Wed, Jul 14, 2004 at 11:24:17AM -0700, Devananda wrote:
> Thanks for the clarification :) However, I'm still not convinced that 
> the index is working in the same fasion as it does for MyISAM and InnoDB 
> tables. Let me explain ... today I filled this table up with 2.5mil rows 
> and then did
> 
> select username from tdata order by username limit 5;
> 
> Since username is indexed I would expect this query not to take very 
> long, and in a MyISAM table it doesn't, but for me with NDB, this takes 
> about a full minute. You can see this same (mis)behaviour in the data I 
> already sent - without the 'order by' clause the statement returns in 
> 0.00 sec (hehe), and when ordered by username, it takes 1.5sec. This was 
> only on 2.5k rows, with no other load on the database - unacceptably slow.
> 
> Do you understand why I think there is a problem? If not, what is 
> unclear in my examples, I will try to clarify.
> 
> Thank you for taking the time to respond :)

Doesn't NDB primarily used hash indexes?  If so, how would you expect
them to help?  It's like HEAP tables before MySQL 4.1.

Jeremy
-- 
Jeremy D. Zawodny, <jzawodn@stripped>
Technical Yahoo - Yahoo MySQL Geek
Desk: (408) 349-7878  Cell: (408) 685-5936
Thread
difficulty with indexesDevananda13 Jul
Re: difficulty with indexesDevananda14 Jul
  • Re: difficulty with indexesJeremy Zawodny14 Jul
    • Re: difficulty with indexesDevananda14 Jul
      • Re: difficulty with indexesDevananda14 Jul
      • Re: difficulty with indexesJonas Oreland14 Jul