diff options
Diffstat (limited to 'activerecord/lib/active_record/relation')
| -rw-r--r-- | activerecord/lib/active_record/relation/finder_methods.rb | 2 | ||||
| -rw-r--r-- | activerecord/lib/active_record/relation/query_methods.rb | 55 |
2 files changed, 51 insertions, 6 deletions
diff --git a/activerecord/lib/active_record/relation/finder_methods.rb b/activerecord/lib/active_record/relation/finder_methods.rb index 74f323a278..e2efd4aa0d 100644 --- a/activerecord/lib/active_record/relation/finder_methods.rb +++ b/activerecord/lib/active_record/relation/finder_methods.rb @@ -7,7 +7,7 @@ module ActiveRecord ONE_AS_ONE = "1 AS one" # Find by id - This can either be a specific id (1), a list of ids (1, 5, 6), or an array of ids ([5, 6, 10]). - # If one or more records can not be found for the requested ids, then ActiveRecord::RecordNotFound will be raised. + # If one or more records cannot be found for the requested ids, then ActiveRecord::RecordNotFound will be raised. # If the primary key is an integer, find by id coerces its arguments by using +to_i+. # # Person.find(1) # returns the object for ID = 1 diff --git a/activerecord/lib/active_record/relation/query_methods.rb b/activerecord/lib/active_record/relation/query_methods.rb index 24a50db619..6f0f2125dc 100644 --- a/activerecord/lib/active_record/relation/query_methods.rb +++ b/activerecord/lib/active_record/relation/query_methods.rb @@ -243,10 +243,10 @@ module ActiveRecord # Allows you to change a previously set select statement. # # Post.select(:title, :body) - # # SELECT `posts.title`, `posts.body` FROM `posts` + # # SELECT `posts`.`title`, `posts`.`body` FROM `posts` # # Post.select(:title, :body).reselect(:created_at) - # # SELECT `posts.created_at` FROM `posts` + # # SELECT `posts`.`created_at` FROM `posts` # # This is short-hand for <tt>unscope(:select).select(fields)</tt>. # Note that we're unscoping the entire select statement. @@ -349,8 +349,8 @@ module ActiveRecord end VALID_UNSCOPING_VALUES = Set.new([:where, :select, :group, :order, :lock, - :limit, :offset, :joins, :left_outer_joins, - :includes, :from, :readonly, :having]) + :limit, :offset, :joins, :left_outer_joins, :annotate, + :includes, :from, :readonly, :having, :optimizer_hints]) # Removes an unwanted relation that is already defined on a chain of relations. # This is useful when passing around chains of relations and would like to @@ -901,6 +901,29 @@ module ActiveRecord self end + # Specify optimizer hints to be used in the SELECT statement. + # + # Example (for MySQL): + # + # Topic.optimizer_hints("MAX_EXECUTION_TIME(50000)", "NO_INDEX_MERGE(topics)") + # # SELECT /*+ MAX_EXECUTION_TIME(50000) NO_INDEX_MERGE(topics) */ `topics`.* FROM `topics` + # + # Example (for PostgreSQL with pg_hint_plan): + # + # Topic.optimizer_hints("SeqScan(topics)", "Parallel(topics 8)") + # # SELECT /*+ SeqScan(topics) Parallel(topics 8) */ "topics".* FROM "topics" + def optimizer_hints(*args) + check_if_method_has_arguments!(:optimizer_hints, args) + spawn.optimizer_hints!(*args) + end + + def optimizer_hints!(*args) # :nodoc: + args.flatten! + + self.optimizer_hints_values += args + self + end + # Reverse the existing order clause on the relation. # # User.order('name ASC').reverse_order # generated SQL has 'ORDER BY name DESC' @@ -925,6 +948,26 @@ module ActiveRecord self end + # Adds an SQL comment to queries generated from this relation. For example: + # + # User.annotate("selecting user names").select(:name) + # # SELECT "users"."name" FROM "users" /* selecting user names */ + # + # User.annotate("selecting", "user", "names").select(:name) + # # SELECT "users"."name" FROM "users" /* selecting */ /* user */ /* names */ + # + # The SQL block comment delimiters, "/*" and "*/", will be added automatically. + def annotate(*args) + check_if_method_has_arguments!(:annotate, args) + spawn.annotate!(*args) + end + + # Like #annotate, but modifies relation in place. + def annotate!(*args) # :nodoc: + self.annotate_values += args + self + end + # Returns the Arel object associated with the relation. def arel(aliases = nil) # :nodoc: @arel ||= build_arel(aliases) @@ -977,9 +1020,11 @@ module ActiveRecord build_select(arel) + arel.optimizer_hints(*optimizer_hints_values) unless optimizer_hints_values.empty? arel.distinct(distinct_value) arel.from(build_from) unless from_clause.empty? arel.lock(lock_value) if lock_value + arel.comment(*annotate_values) unless annotate_values.empty? arel end @@ -1117,7 +1162,7 @@ module ActiveRecord o.reverse when String if does_not_support_reverse?(o) - raise IrreversibleOrderError, "Order #{o.inspect} can not be reversed automatically" + raise IrreversibleOrderError, "Order #{o.inspect} cannot be reversed automatically" end o.split(",").map! do |s| s.strip! |