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| author | Maurizio De Santis <desantis.maurizio@gmail.com> | 2013-02-07 21:24:45 +0100 |
|---|---|---|
| committer | Maurizio De Santis <desantis.maurizio@gmail.com> | 2013-02-07 21:24:45 +0100 |
| commit | a8c2981f62555a7ea7e5b378509fca6009ba8a8e (patch) | |
| tree | bf7b645b0309f7820bd92078ba166191e9ecf8d8 /activerecord/lib/active_record | |
| parent | d47b90e76c989a8f0ca32c140e9b7220da0e5edc (diff) | |
| download | rails-a8c2981f62555a7ea7e5b378509fca6009ba8a8e.tar.gz rails-a8c2981f62555a7ea7e5b378509fca6009ba8a8e.tar.bz2 rails-a8c2981f62555a7ea7e5b378509fca6009ba8a8e.zip | |
Add ActiveRecord.count documentation when used on group relations
Diffstat (limited to 'activerecord/lib/active_record')
| -rw-r--r-- | activerecord/lib/active_record/relation/calculations.rb | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/activerecord/lib/active_record/relation/calculations.rb b/activerecord/lib/active_record/relation/calculations.rb index f10c290755..3fc079d84c 100644 --- a/activerecord/lib/active_record/relation/calculations.rb +++ b/activerecord/lib/active_record/relation/calculations.rb @@ -13,6 +13,12 @@ module ActiveRecord # # Person.count(:age, distinct: true) # # => counts the number of different age values + # + # If used on a +group+, it returns a Hash whose keys represent the aggregated column, + # and the values are the respective amounts: + # + # Person.group(:city).count + # # => { 'Rome' => 5, 'Paris' => 3 } def count(column_name = nil, options = {}) column_name, options = nil, column_name if column_name.is_a?(Hash) calculate(:count, column_name, options) |