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PORails 3 - How to get the row number from a model with an order by
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copied!<p>I am putting together a small app that has a leaderboard concept in it. Basically, the model is just a player_name and a current_score.</p> <p>what I want to do is get the ranking of a specific player, and given that new scores are coming in all the time, it needs to be dynamic. Obviously I could just do a normal find with an order by clause and then I would have to loop through each record. Not very efficient when I could have 100,000's of rows. </p> <p>Any suggestions on what approach I should be taking?</p> <p>Here is the migration for the table:</p> <pre><code>class CreateScores < ActiveRecord::Migration def self.up create_table :scores do |t| t.string :player_name t.integer :current_score t.timestamps end end def self.down drop_table :scores end end </code></pre> <p>EDIT As an example, so I have the following:</p> <pre><code>Score.select('player_name, current_score').limit(20) => [#<Score player_name: "Keith Hughes", current_score: 9>, #<Score player_name: "Diane Chapman", current_score: 8>, #<Score player_name: "Helen Dixon", current_score: 4>, #<Score player_name: "Donald Lynch", current_score: 9>, #<Score player_name: "Shawn Snyder", current_score: 2>, #<Score player_name: "Nancy Palmer", current_score: 9>, #<Score player_name: "Janet Arnold", current_score: 1>, #<Score player_name: "Sharon Torres", current_score: 9>, #<Score player_name: "Keith Ortiz", current_score: 5>, #<Score player_name: "Judith Day", current_score: 3>, #<Score player_name: "Gregory Watson", current_score: 7>, #<Score player_name: "Jeremy Welch", current_score: 3>, #<Score player_name: "Sharon Oliver", current_score: 7>, #<Score player_name: "Donald Lewis", current_score: 7>, #<Score player_name: "Timothy Frazier", current_score: 7>, #<Score player_name: "John Richards", current_score: 1>, #<Score player_name: "Carolyn White", current_score: 4>, #<Score player_name: "Ronald Smith", current_score: 2>, #<Score player_name: "Emily Freeman", current_score: 9>, #<Score player_name: "Gregory Wright", current_score: 2>] </code></pre> <p>How can I work out the ranking of "Donald Lewis" ?</p>

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