diff options
Diffstat (limited to 'activerecord/lib')
| -rw-r--r-- | activerecord/lib/active_record/connection_adapters/connection_specification.rb | 18 | ||||
| -rw-r--r-- | activerecord/lib/active_record/relation/finder_methods.rb | 25 |
2 files changed, 27 insertions, 16 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/connection_specification.rb b/activerecord/lib/active_record/connection_adapters/connection_specification.rb index 29542f917e..e9bda1885b 100644 --- a/activerecord/lib/active_record/connection_adapters/connection_specification.rb +++ b/activerecord/lib/active_record/connection_adapters/connection_specification.rb @@ -183,13 +183,25 @@ module ActiveRecord raise(AdapterNotSpecified, "database configuration does not specify adapter") unless spec.key?(:adapter) + # Require the adapter itself and give useful feedback about + # 1. Missing adapter gems and + # 2. Adapter gems' missing dependencies. path_to_adapter = "active_record/connection_adapters/#{spec[:adapter]}_adapter" begin require path_to_adapter - rescue Gem::LoadError => e - raise Gem::LoadError, "Specified '#{spec[:adapter]}' for database adapter, but the gem is not loaded. Add `gem '#{e.name}'` to your Gemfile (and ensure its version is at the minimum required by ActiveRecord)." rescue LoadError => e - raise LoadError, "Could not load '#{path_to_adapter}'. Make sure that the adapter in config/database.yml is valid. If you use an adapter other than 'mysql2', 'postgresql' or 'sqlite3' add the necessary adapter gem to the Gemfile.", e.backtrace + # We couldn't require the adapter itself. Raise an exception that + # points out config typos and missing gems. + if e.path == path_to_adapter + # We can assume that a non-builtin adapter was specified, so it's + # either misspelled or missing from Gemfile. + raise e.class, "Could not load the '#{spec[:adapter]}' Active Record adapter. Ensure that the adapter is spelled correctly in config/database.yml and that you've added the necessary adapter gem to your Gemfile.", e.backtrace + + # Bubbled up from the adapter require. Prefix the exception message + # with some guidance about how to address it and reraise. + else + raise e.class, "Error loading the '#{spec[:adapter]}' Action Record adapter. Missing a gem it depends on? #{e.message}", e.backtrace + end end adapter_method = "#{spec[:adapter]}_connection" diff --git a/activerecord/lib/active_record/relation/finder_methods.rb b/activerecord/lib/active_record/relation/finder_methods.rb index 5d4b549470..5ccfe3d1b7 100644 --- a/activerecord/lib/active_record/relation/finder_methods.rb +++ b/activerecord/lib/active_record/relation/finder_methods.rb @@ -310,12 +310,12 @@ module ActiveRecord return false if !conditions || limit_value == 0 - relation = self unless eager_loading? - relation ||= apply_join_dependency(self, construct_join_dependency(eager_loading: false)) - - return false if ActiveRecord::NullRelation === relation + if eager_loading? + relation = apply_join_dependency(construct_join_dependency(eager_loading: false)) + return relation.exists?(conditions) + end - relation = construct_relation_for_exists(relation, conditions) + relation = construct_relation_for_exists(conditions) skip_query_cache_if_necessary { connection.select_value(relation.arel, "#{name} Exists") } ? true : false rescue ::RangeError @@ -368,15 +368,14 @@ module ActiveRecord # join_dependency = construct_join_dependency(joins_values) - aliases = join_dependency.aliases - relation = select aliases.columns - relation = apply_join_dependency(relation, join_dependency) + relation = apply_join_dependency(join_dependency) + relation._select!(join_dependency.aliases.columns) yield relation, join_dependency end - def construct_relation_for_exists(relation, conditions) - relation = relation.except(:select, :distinct, :order)._select!(ONE_AS_ONE).limit!(1) + def construct_relation_for_exists(conditions) + relation = except(:select, :distinct, :order)._select!(ONE_AS_ONE).limit!(1) case conditions when Array, Hash @@ -396,11 +395,11 @@ module ActiveRecord end def construct_relation_for_association_calculations - apply_join_dependency(self, construct_join_dependency(joins_values)) + apply_join_dependency(construct_join_dependency(joins_values)) end - def apply_join_dependency(relation, join_dependency) - relation = relation.except(:includes, :eager_load, :preload).joins!(join_dependency) + def apply_join_dependency(join_dependency) + relation = except(:includes, :eager_load, :preload).joins!(join_dependency) if using_limitable_reflections?(join_dependency.reflections) relation |