diff options
Diffstat (limited to 'activerecord/lib/active_record/result.rb')
-rw-r--r-- | activerecord/lib/active_record/result.rb | 44 |
1 files changed, 41 insertions, 3 deletions
diff --git a/activerecord/lib/active_record/result.rb b/activerecord/lib/active_record/result.rb index a7a035fe46..d0f1cb5b75 100644 --- a/activerecord/lib/active_record/result.rb +++ b/activerecord/lib/active_record/result.rb @@ -3,8 +3,31 @@ module ActiveRecord # This class encapsulates a Result returned from calling +exec_query+ on any # database connection adapter. For example: # - # x = ActiveRecord::Base.connection.exec_query('SELECT * FROM foo') - # x # => #<ActiveRecord::Result:0xdeadbeef> + # result = ActiveRecord::Base.connection.exec_query('SELECT id, title, body FROM posts') + # result # => #<ActiveRecord::Result:0xdeadbeef> + # + # # Get the column names of the result: + # result.columns + # # => ["id", "title", "body"] + # + # # Get the record values of the result: + # result.rows + # # => [[1, "title_1", "body_1"], + # [2, "title_2", "body_2"], + # ... + # ] + # + # # Get an array of hashes representing the result (column => value): + # result.to_hash + # # => [{"id" => 1, "title" => "title_1", "body" => "body_1"}, + # {"id" => 2, "title" => "title_2", "body" => "body_2"}, + # ... + # ] + # + # # ActiveRecord::Result also includes Enumerable. + # result.each do |row| + # puts row['title'] + " " + row['body'] + # end class Result include Enumerable @@ -62,6 +85,7 @@ module ActiveRecord end private + def hash_rows @hash_rows ||= begin @@ -69,7 +93,21 @@ module ActiveRecord # used as keys in ActiveRecord::Base's @attributes hash columns = @columns.map { |c| c.dup.freeze } @rows.map { |row| - Hash[columns.zip(row)] + # In the past we used Hash[columns.zip(row)] + # though elegant, the verbose way is much more efficient + # both time and memory wise cause it avoids a big array allocation + # this method is called a lot and needs to be micro optimised + hash = {} + + index = 0 + length = columns.length + + while index < length + hash[columns[index]] = row[index] + index += 1 + end + + hash } end end |