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    <pre><code>rename_column :table, :old_column, :new_column </code></pre> <p><strong>Update:</strong></p> <p>You'll probably want to create a separate migration to do this. (Rename FixColumnName as you will)</p> <pre><code>script/generate migration FixColumnName # creates db/migrate/xxxxxxxxxx_fix_column_name.rb </code></pre> <p>Then edit the migration to do your will.</p> <pre><code># db/migrate/xxxxxxxxxx_fix_column_name.rb class FixColumnName &lt; ActiveRecord::Migration def self.up rename_column :table_name, :old_column, :new_column end def self.down # rename back if you need or do something else or do nothing end end </code></pre> <hr> <p><strong>An update for Rails 3.1</strong></p> <p>While, the <code>up</code> and <code>down</code> methods still apply. Rails 3.1 receives a <code>change</code> method that <a href="http://guides.rubyonrails.org/migrations.html" rel="noreferrer">"knows how to migrate your database and reverse it when the migration is rolled back without the need to write a separate down method"</a></p> <pre><code>rails g migration FixColumnName class FixColumnName &lt; ActiveRecord::Migration def change rename_column :table_name, :old_column, :new_column end end </code></pre> <hr> <p>If you happen to have a whole bunch of columns to rename, or something that would have required repeating the table name over and over again.</p> <pre><code>rename_column :table_name, :old_column1, :new_column1 rename_column :table_name, :old_column2, :new_column2 ... </code></pre> <p>You could use <code>change_table</code> to keep things a little neater.</p> <pre><code>class FixColumnNames &lt; ActiveRecord::Migration def change change_table :table_name do |t| t.rename :old_column1, :new_column1 t.rename :old_column2, :new_column2 ... end end end </code></pre> <p><em>Thank you, <code>Luke</code> &amp;&amp; <code>Turadg</code>, for bringing up the topic.</em></p> <p>Then just <code>db:migrate</code> as usual or however you go about your business.</p> <hr> <p><strong>An update for Rails 4</strong></p> <p>While creating a <code>Migration</code> as for renaming a column, Rails 4 generates a <code>change</code> method instead of <code>up</code> and <code>down</code> as mentioned in the above answer. The generated <code>change</code> method is as below : </p> <pre><code>$ &gt; rails g migration ChangeColumnName </code></pre> <p>which will create a migration file similar to this :</p> <pre><code>class ChangeColumnName &lt; ActiveRecord::Migration def change rename_column :table_name, :old_column, :new_column end end </code></pre>
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    1. POHow can I rename a database column in a Ruby on Rails migration?
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    1. POHow can I rename a database column in a Ruby on Rails migration?
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    1. COself.down should *always* be the opposite of self.up, so "if you need or do something else or do nothing" isn't really recommended. Just do: rename_column :table_name, :new_column, :old_column
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    2. COWhile it's normal practice to revert what you did in `self.up` I would not say `self.down` "should *always* be opposite". In depends on the context of your migration. Just putting the "opposite" might not be the "right" down migration.
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    3. COIn Rails 3.1 you can replace `def self.up` and `def self.down` with `def change` and it'll know how to rollback.
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