Quoting Greg Brockman <[email protected]>:
>
> Hello all,
>
> This is my first post to this group, so please let me know if there is
> any protocol I'm supposed to follow that I missed. Anyway, I've been
> developing a Rails application for handling the registration and score
> data of a math competition. There is an existing Java applet that we
> use that generates the score data with reference to problem_id,
> solver_id, and the result (which is - if blank, 0 if wrong, 1 if
> right, and =n if n points of partial credit are to be awarded). It
> saves each individual's answer to each question as a separate row in
> the scores table.
>
> I've wrote a script to process this data in Rails. However, in 2008
> there were over 15,000 rows in the scores table, and my current code
> loads every one of them. My current load time is about 5 seconds, and
> I think it's due to making an ActiveRecord object for every one. Is
> there a way to bypass making a separate object for each? I do need
> access to the data, but it would be nicest as an array or something
> under Solver. One solution I'm currently considering is using raw SQL
> for this, but I thought I'd see if anyone had any thoughts to weigh
> in.
>
There are several ways:
* A Problem has_many Scores, a Solver has_many Score, and A Score belongs_to
both a Problem and a Solver. Process one Problem at a time, or one Solver
at a time.
* SQL, e.g. select_rows('SELECT problem_id, solver_id, result FROM scores')
Returns an array of array of strings with the values in the order specified.
E.g. [['123', '345', '-'], # problem 123, solver 345, result '-'
['124', '1024', '123'], # problem 123, solver 1024, result '123'
...
Remember, all values are strings and may need to be converted to integers.
* Use will_paginate to retrieve results in clumps, e.g. 100 results at a time.
HTH,
Jeffrey
--~--~---------~--~----~------------~-------~--~----~
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
-~----------~----~----~----~------~----~------~--~---
