On 20 Dec 2008, at 16:45, Jeff Pritchard wrote:
> > Frederick Cheung wrote: >> On 20 Dec 2008, at 07:11, Marnen Laibow-Koser wrote: >> >>> [...] >>> >>> Very simple: you can profit by indexing on almost anything you're >> All of the above is good. To explain a little more if you do >> >> SELECT * from contacts where contacts.user_id = 2356 >> >> and there is no index then the database must examine every single row >> in the contacts table to see if it has the right user_id whereas if >> it >> has an index it can go straight there. (similar to how if you have a >> >> Fred > > Thanks Marnen and Fred, > Does the same logic completely cover joins Yup Fred > , or is there something > special to consider for those? > > thanks, > jp > -- > Posted via http://www.ruby-forum.com/. > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Ruby on Rails: Talk" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/rubyonrails-talk?hl=en -~----------~----~----~----~------~----~------~--~---
