Adding Index on Heroku without a Restart

add_index_patch.rb

module ActiveRecord::ConnectionAdapters::SchemaStatements

  def add_index_with_quiet(table_name, column_names, options = {})
    quiet = options.delete(:quiet)
    add_index_without_quiet table_name, column_names, options
  rescue
    raise unless quiet and $!.message =~ /^Index name '.*' on table '#{table_name}' already exists/i
    puts "Failed to create index #{table_name} #{column_names.inspect} #{options.inspect}"
  end
  alias_method_chain :add_index, :quiet

end

gistfile1.rb

heroku run console --app <your app name>

irb(main):002:0* class AddIndexToSearches < ActiveRecord::Migration
irb(main):003:1>   def change
irb(main):004:2>     add_index :searches, :search_string, :quiet => true
irb(main):005:2>   end
irb(main):006:1> end
=> nil
irb(main):007:0> t = AddIndexToSearches.new
=> #<AddIndexToSearches:0x00000006a240a8 @name="AddIndexToSearches", @version=nil, @connection=nil>
irb(main):008:0> t.change
-- add_index(:searches, :search_string)
   (91.8ms)   SELECT distinct i.relname, d.indisunique, d.indkey, t.oid
 FROM pg_class t
 INNER JOIN pg_index d ON t.oid = d.indrelid
 INNER JOIN pg_class i ON d.indexrelid = i.oid
 WHERE i.relkind = 'i'
 AND d.indisprimary = 'f'
 AND t.relname = 'searches'
 AND i.relnamespace IN (SELECT oid FROM pg_namespace WHERE nspname = ANY (current_schemas(false)) )
 ORDER BY i.relname


   (207509.6ms)  CREATE INDEX "index_searches_on_search_string" ON "searches" ("search_string")
   -> 207.6028s
=> #<PGresult:0x00000006c81328>
irb(main):009:0> 
irb(main):010:0*