diff options
Diffstat (limited to 'activerecord/lib/active_record/relation.rb')
-rw-r--r-- | activerecord/lib/active_record/relation.rb | 62 |
1 files changed, 42 insertions, 20 deletions
diff --git a/activerecord/lib/active_record/relation.rb b/activerecord/lib/active_record/relation.rb index 7d37313058..e47b7b1ed9 100644 --- a/activerecord/lib/active_record/relation.rb +++ b/activerecord/lib/active_record/relation.rb @@ -15,6 +15,7 @@ module ActiveRecord VALUE_METHODS = MULTI_VALUE_METHODS + SINGLE_VALUE_METHODS + CLAUSE_METHODS + include Enumerable include FinderMethods, Calculations, SpawnMethods, QueryMethods, Batches, Explain, Delegation attr_reader :table, :klass, :loaded, :predicate_builder @@ -275,38 +276,52 @@ module ActiveRecord # Returns true if there are no records. def none? - if block_given? - to_a.none? { |*block_args| yield(*block_args) } - else - empty? - end + return super if block_given? + empty? end # Returns true if there are any records. def any? - if block_given? - to_a.any? { |*block_args| yield(*block_args) } - else - !empty? - end + return super if block_given? + !empty? end # Returns true if there is exactly one record. def one? - if block_given? - to_a.one? { |*block_args| yield(*block_args) } - else - limit_value ? to_a.one? : size == 1 - end + return super if block_given? + limit_value ? to_a.one? : size == 1 end # Returns true if there is more than one record. def many? - if block_given? - to_a.many? { |*block_args| yield(*block_args) } - else - limit_value ? to_a.many? : size > 1 - end + return super if block_given? + limit_value ? to_a.many? : size > 1 + end + + # Returns a cache key that can be used to identify the records fetched by + # this query. The cache key is built with a fingerprint of the sql query, + # the number of records matched by the query and a timestamp of the last + # updated record. When a new record comes to match the query, or any of + # the existing records is updated or deleted, the cache key changes. + # + # Product.where("name like ?", "%Cosmic Encounter%").cache_key + # => "products/query-1850ab3d302391b85b8693e941286659-1-20150714212553907087000" + # + # If the collection is loaded, the method will iterate through the records + # to generate the timestamp, otherwise it will trigger one SQL query like: + # + # SELECT COUNT(*), MAX("products"."updated_at") FROM "products" WHERE (name like '%Cosmic Encounter%') + # + # You can also pass a custom timestamp column to fetch the timestamp of the + # last updated record. + # + # Product.where("name like ?", "%Game%").cache_key(:last_reviewed_at) + # + # You can customize the strategy to generate the key on a per model basis + # overriding ActiveRecord::Base#collection_cache_key. + def cache_key(timestamp_column = :updated_at) + @cache_keys ||= {} + @cache_keys[timestamp_column] ||= @klass.collection_cache_key(self, timestamp_column) end # Scope all queries to the current scope. @@ -652,6 +667,13 @@ module ActiveRecord "#<#{self.class.name} [#{entries.join(', ')}]>" end + protected + + def load_records(records) + @records = records + @loaded = true + end + private def exec_queries |