diff options
Diffstat (limited to 'activerecord/lib/active_record/relation')
5 files changed, 493 insertions, 253 deletions
diff --git a/activerecord/lib/active_record/relation/calculation_methods.rb b/activerecord/lib/active_record/relation/calculation_methods.rb deleted file mode 100644 index 91de89e607..0000000000 --- a/activerecord/lib/active_record/relation/calculation_methods.rb +++ /dev/null @@ -1,172 +0,0 @@ -module ActiveRecord - module CalculationMethods - - def count(*args) - calculate(:count, *construct_count_options_from_args(*args)) - end - - def average(column_name) - calculate(:average, column_name) - end - - def minimum(column_name) - calculate(:minimum, column_name) - end - - def maximum(column_name) - calculate(:maximum, column_name) - end - - def sum(column_name) - calculate(:sum, column_name) - end - - def calculate(operation, column_name, options = {}) - operation = operation.to_s.downcase - - if operation == "count" - joins = arel.joins(arel) - if joins.present? && joins =~ /LEFT OUTER/i - distinct = true - column_name = @klass.primary_key if column_name == :all - end - - distinct = nil if column_name.to_s =~ /\s*DISTINCT\s+/i - distinct ||= options[:distinct] - else - distinct = nil - end - - distinct = options[:distinct] || distinct - column_name = :all if column_name.blank? && operation == "count" - - if @group_values.any? - return execute_grouped_calculation(operation, column_name) - else - return execute_simple_calculation(operation, column_name, distinct) - end - rescue ThrowResult - 0 - end - - private - - def execute_simple_calculation(operation, column_name, distinct) #:nodoc: - column = if @klass.column_names.include?(column_name.to_s) - Arel::Attribute.new(@klass.unscoped, column_name) - else - Arel::SqlLiteral.new(column_name == :all ? "*" : column_name.to_s) - end - - relation = select(operation == 'count' ? column.count(distinct) : column.send(operation)) - type_cast_calculated_value(@klass.connection.select_value(relation.to_sql), column_for(column_name), operation) - end - - def execute_grouped_calculation(operation, column_name) #:nodoc: - group_attr = @group_values.first - association = @klass.reflect_on_association(group_attr.to_sym) - associated = association && association.macro == :belongs_to # only count belongs_to associations - group_field = associated ? association.primary_key_name : group_attr - group_alias = column_alias_for(group_field) - group_column = column_for(group_field) - - group = @klass.connection.adapter_name == 'FrontBase' ? group_alias : group_field - - aggregate_alias = column_alias_for(operation, column_name) - - select_statement = if operation == 'count' && column_name == :all - "COUNT(*) AS count_all" - else - Arel::Attribute.new(@klass.unscoped, column_name).send(operation).as(aggregate_alias).to_sql - end - - select_statement << ", #{group_field} AS #{group_alias}" - - relation = select(select_statement).group(group) - - calculated_data = @klass.connection.select_all(relation.to_sql) - - if association - key_ids = calculated_data.collect { |row| row[group_alias] } - key_records = association.klass.base_class.find(key_ids) - key_records = key_records.inject({}) { |hsh, r| hsh.merge(r.id => r) } - end - - calculated_data.inject(ActiveSupport::OrderedHash.new) do |all, row| - key = type_cast_calculated_value(row[group_alias], group_column) - key = key_records[key] if associated - value = row[aggregate_alias] - all[key] = type_cast_calculated_value(value, column_for(column_name), operation) - all - end - end - - def construct_count_options_from_args(*args) - options = {} - column_name = :all - - # Handles count(), count(:column), count(:distinct => true), count(:column, :distinct => true) - case args.size - when 0 - select = get_projection_name_from_chained_relations - column_name = select if select !~ /(,|\*)/ - when 1 - if args[0].is_a?(Hash) - select = get_projection_name_from_chained_relations - column_name = select if select !~ /(,|\*)/ - options = args[0] - else - column_name = args[0] - end - when 2 - column_name, options = args - else - raise ArgumentError, "Unexpected parameters passed to count(): #{args.inspect}" - end - - [column_name || :all, options] - end - - # Converts the given keys to the value that the database adapter returns as - # a usable column name: - # - # column_alias_for("users.id") # => "users_id" - # column_alias_for("sum(id)") # => "sum_id" - # column_alias_for("count(distinct users.id)") # => "count_distinct_users_id" - # column_alias_for("count(*)") # => "count_all" - # column_alias_for("count", "id") # => "count_id" - def column_alias_for(*keys) - table_name = keys.join(' ') - table_name.downcase! - table_name.gsub!(/\*/, 'all') - table_name.gsub!(/\W+/, ' ') - table_name.strip! - table_name.gsub!(/ +/, '_') - - @klass.connection.table_alias_for(table_name) - end - - def column_for(field) - field_name = field.to_s.split('.').last - @klass.columns.detect { |c| c.name.to_s == field_name } - end - - def type_cast_calculated_value(value, column, operation = nil) - case operation - when 'count' then value.to_i - when 'sum' then type_cast_using_column(value || '0', column) - when 'average' then value && (value.is_a?(Fixnum) ? value.to_f : value).to_d - else type_cast_using_column(value, column) - end - end - - def type_cast_using_column(value, column) - column ? column.type_cast(value) : value - end - - def get_projection_name_from_chained_relations - @select_values.join(", ") if @select_values.present? - end - - end -end diff --git a/activerecord/lib/active_record/relation/calculations.rb b/activerecord/lib/active_record/relation/calculations.rb new file mode 100644 index 0000000000..e77424a64b --- /dev/null +++ b/activerecord/lib/active_record/relation/calculations.rb @@ -0,0 +1,259 @@ +module ActiveRecord + module Calculations + # Count operates using three different approaches. + # + # * Count all: By not passing any parameters to count, it will return a count of all the rows for the model. + # * Count using column: By passing a column name to count, it will return a count of all the rows for the model with supplied column present + # * Count using options will find the row count matched by the options used. + # + # The third approach, count using options, accepts an option hash as the only parameter. The options are: + # + # * <tt>:conditions</tt>: An SQL fragment like "administrator = 1" or [ "user_name = ?", username ]. See conditions in the intro to ActiveRecord::Base. + # * <tt>:joins</tt>: Either an SQL fragment for additional joins like "LEFT JOIN comments ON comments.post_id = id" (rarely needed) + # or named associations in the same form used for the <tt>:include</tt> option, which will perform an INNER JOIN on the associated table(s). + # If the value is a string, then the records will be returned read-only since they will have attributes that do not correspond to the table's columns. + # Pass <tt>:readonly => false</tt> to override. + # * <tt>:include</tt>: Named associations that should be loaded alongside using LEFT OUTER JOINs. The symbols named refer + # to already defined associations. When using named associations, count returns the number of DISTINCT items for the model you're counting. + # See eager loading under Associations. + # * <tt>:order</tt>: An SQL fragment like "created_at DESC, name" (really only used with GROUP BY calculations). + # * <tt>:group</tt>: An attribute name by which the result should be grouped. Uses the GROUP BY SQL-clause. + # * <tt>:select</tt>: By default, this is * as in SELECT * FROM, but can be changed if you, for example, want to do a join but not + # include the joined columns. + # * <tt>:distinct</tt>: Set this to true to make this a distinct calculation, such as SELECT COUNT(DISTINCT posts.id) ... + # * <tt>:from</tt> - By default, this is the table name of the class, but can be changed to an alternate table name (or even the name + # of a database view). + # + # Examples for counting all: + # Person.count # returns the total count of all people + # + # Examples for counting by column: + # Person.count(:age) # returns the total count of all people whose age is present in database + # + # Examples for count with options: + # Person.count(:conditions => "age > 26") + # Person.count(:conditions => "age > 26 AND job.salary > 60000", :include => :job) # because of the named association, it finds the DISTINCT count using LEFT OUTER JOIN. + # Person.count(:conditions => "age > 26 AND job.salary > 60000", :joins => "LEFT JOIN jobs on jobs.person_id = person.id") # finds the number of rows matching the conditions and joins. + # Person.count('id', :conditions => "age > 26") # Performs a COUNT(id) + # Person.count(:all, :conditions => "age > 26") # Performs a COUNT(*) (:all is an alias for '*') + # + # Note: <tt>Person.count(:all)</tt> will not work because it will use <tt>:all</tt> as the condition. Use Person.count instead. + def count(column_name = nil, options = {}) + column_name, options = nil, column_name if column_name.is_a?(Hash) + calculate(:count, column_name, options) + end + + # Calculates the average value on a given column. The value is returned as + # a float, or +nil+ if there's no row. See +calculate+ for examples with + # options. + # + # Person.average('age') # => 35.8 + def average(column_name, options = {}) + calculate(:average, column_name, options) + end + + # Calculates the minimum value on a given column. The value is returned + # with the same data type of the column, or +nil+ if there's no row. See + # +calculate+ for examples with options. + # + # Person.minimum('age') # => 7 + def minimum(column_name, options = {}) + calculate(:minimum, column_name, options) + end + + # Calculates the maximum value on a given column. The value is returned + # with the same data type of the column, or +nil+ if there's no row. See + # +calculate+ for examples with options. + # + # Person.maximum('age') # => 93 + def maximum(column_name, options = {}) + calculate(:maximum, column_name, options) + end + + # Calculates the sum of values on a given column. The value is returned + # with the same data type of the column, 0 if there's no row. See + # +calculate+ for examples with options. + # + # Person.sum('age') # => 4562 + def sum(column_name, options = {}) + calculate(:sum, column_name, options) + end + + # This calculates aggregate values in the given column. Methods for count, sum, average, minimum, and maximum have been added as shortcuts. + # Options such as <tt>:conditions</tt>, <tt>:order</tt>, <tt>:group</tt>, <tt>:having</tt>, and <tt>:joins</tt> can be passed to customize the query. + # + # There are two basic forms of output: + # * Single aggregate value: The single value is type cast to Fixnum for COUNT, Float for AVG, and the given column's type for everything else. + # * Grouped values: This returns an ordered hash of the values and groups them by the <tt>:group</tt> option. It takes either a column name, or the name + # of a belongs_to association. + # + # values = Person.maximum(:age, :group => 'last_name') + # puts values["Drake"] + # => 43 + # + # drake = Family.find_by_last_name('Drake') + # values = Person.maximum(:age, :group => :family) # Person belongs_to :family + # puts values[drake] + # => 43 + # + # values.each do |family, max_age| + # ... + # end + # + # Options: + # * <tt>:conditions</tt> - An SQL fragment like "administrator = 1" or [ "user_name = ?", username ]. See conditions in the intro to ActiveRecord::Base. + # * <tt>:include</tt>: Eager loading, see Associations for details. Since calculations don't load anything, the purpose of this is to access fields on joined tables in your conditions, order, or group clauses. + # * <tt>:joins</tt> - An SQL fragment for additional joins like "LEFT JOIN comments ON comments.post_id = id". (Rarely needed). + # The records will be returned read-only since they will have attributes that do not correspond to the table's columns. + # * <tt>:order</tt> - An SQL fragment like "created_at DESC, name" (really only used with GROUP BY calculations). + # * <tt>:group</tt> - An attribute name by which the result should be grouped. Uses the GROUP BY SQL-clause. + # * <tt>:select</tt> - By default, this is * as in SELECT * FROM, but can be changed if you for example want to do a join, but not + # include the joined columns. + # * <tt>:distinct</tt> - Set this to true to make this a distinct calculation, such as SELECT COUNT(DISTINCT posts.id) ... + # + # Examples: + # Person.calculate(:count, :all) # The same as Person.count + # Person.average(:age) # SELECT AVG(age) FROM people... + # Person.minimum(:age, :conditions => ['last_name != ?', 'Drake']) # Selects the minimum age for everyone with a last name other than 'Drake' + # Person.minimum(:age, :having => 'min(age) > 17', :group => :last_name) # Selects the minimum age for any family without any minors + # Person.sum("2 * age") + def calculate(operation, column_name, options = {}) + if options.except(:distinct).present? + apply_finder_options(options.except(:distinct)).calculate(operation, column_name, :distinct => options[:distinct]) + else + if eager_loading? || includes_values.present? + construct_relation_for_association_calculations.calculate(operation, column_name, options) + else + perform_calculation(operation, column_name, options) + end + end + rescue ThrowResult + 0 + end + + private + + def perform_calculation(operation, column_name, options = {}) + operation = operation.to_s.downcase + + if operation == "count" + column_name ||= (select_for_count || :all) + + joins = arel.joins(arel) + if joins.present? && joins =~ /LEFT OUTER/i + distinct = true + column_name = @klass.primary_key if column_name == :all + end + + distinct = nil if column_name.to_s =~ /\s*DISTINCT\s+/i + distinct ||= options[:distinct] + else + distinct = nil + end + + distinct = options[:distinct] || distinct + column_name = :all if column_name.blank? && operation == "count" + + if @group_values.any? + return execute_grouped_calculation(operation, column_name) + else + return execute_simple_calculation(operation, column_name, distinct) + end + end + + def execute_simple_calculation(operation, column_name, distinct) #:nodoc: + column = if @klass.column_names.include?(column_name.to_s) + Arel::Attribute.new(@klass.unscoped, column_name) + else + Arel::SqlLiteral.new(column_name == :all ? "*" : column_name.to_s) + end + + # Postgresql doesn't like ORDER BY when there are no GROUP BY + relation = except(:order).select(operation == 'count' ? column.count(distinct) : column.send(operation)) + type_cast_calculated_value(@klass.connection.select_value(relation.to_sql), column_for(column_name), operation) + end + + def execute_grouped_calculation(operation, column_name) #:nodoc: + group_attr = @group_values.first + association = @klass.reflect_on_association(group_attr.to_sym) + associated = association && association.macro == :belongs_to # only count belongs_to associations + group_field = associated ? association.primary_key_name : group_attr + group_alias = column_alias_for(group_field) + group_column = column_for(group_field) + + group = @klass.connection.adapter_name == 'FrontBase' ? group_alias : group_field + + aggregate_alias = column_alias_for(operation, column_name) + + select_statement = if operation == 'count' && column_name == :all + "COUNT(*) AS count_all" + else + Arel::Attribute.new(@klass.unscoped, column_name).send(operation).as(aggregate_alias).to_sql + end + + select_statement << ", #{group_field} AS #{group_alias}" + + relation = select(select_statement).group(group) + + calculated_data = @klass.connection.select_all(relation.to_sql) + + if association + key_ids = calculated_data.collect { |row| row[group_alias] } + key_records = association.klass.base_class.find(key_ids) + key_records = key_records.inject({}) { |hsh, r| hsh.merge(r.id => r) } + end + + calculated_data.inject(ActiveSupport::OrderedHash.new) do |all, row| + key = type_cast_calculated_value(row[group_alias], group_column) + key = key_records[key] if associated + value = row[aggregate_alias] + all[key] = type_cast_calculated_value(value, column_for(column_name), operation) + all + end + end + + # Converts the given keys to the value that the database adapter returns as + # a usable column name: + # + # column_alias_for("users.id") # => "users_id" + # column_alias_for("sum(id)") # => "sum_id" + # column_alias_for("count(distinct users.id)") # => "count_distinct_users_id" + # column_alias_for("count(*)") # => "count_all" + # column_alias_for("count", "id") # => "count_id" + def column_alias_for(*keys) + table_name = keys.join(' ') + table_name.downcase! + table_name.gsub!(/\*/, 'all') + table_name.gsub!(/\W+/, ' ') + table_name.strip! + table_name.gsub!(/ +/, '_') + + @klass.connection.table_alias_for(table_name) + end + + def column_for(field) + field_name = field.to_s.split('.').last + @klass.columns.detect { |c| c.name.to_s == field_name } + end + + def type_cast_calculated_value(value, column, operation = nil) + case operation + when 'count' then value.to_i + when 'sum' then type_cast_using_column(value || '0', column) + when 'average' then value && (value.is_a?(Fixnum) ? value.to_f : value).to_d + else type_cast_using_column(value, column) + end + end + + def type_cast_using_column(value, column) + column ? column.type_cast(value) : value + end + + def select_for_count + if @select_values.present? + select = @select_values.join(", ") + select if select !~ /(,|\*)/ + end + end + end +end diff --git a/activerecord/lib/active_record/relation/finder_methods.rb b/activerecord/lib/active_record/relation/finder_methods.rb index 980c5796f3..d6d3d66642 100644 --- a/activerecord/lib/active_record/relation/finder_methods.rb +++ b/activerecord/lib/active_record/relation/finder_methods.rb @@ -1,44 +1,157 @@ module ActiveRecord module FinderMethods - - def find(*ids, &block) + # Find operates with four different retrieval approaches: + # + # * 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 no record can be found for all of the listed ids, then RecordNotFound will be raised. + # * Find first - This will return the first record matched by the options used. These options can either be specific + # conditions or merely an order. If no record can be matched, +nil+ is returned. Use + # <tt>Model.find(:first, *args)</tt> or its shortcut <tt>Model.first(*args)</tt>. + # * Find last - This will return the last record matched by the options used. These options can either be specific + # conditions or merely an order. If no record can be matched, +nil+ is returned. Use + # <tt>Model.find(:last, *args)</tt> or its shortcut <tt>Model.last(*args)</tt>. + # * Find all - This will return all the records matched by the options used. + # If no records are found, an empty array is returned. Use + # <tt>Model.find(:all, *args)</tt> or its shortcut <tt>Model.all(*args)</tt>. + # + # All approaches accept an options hash as their last parameter. + # + # ==== Parameters + # + # * <tt>:conditions</tt> - An SQL fragment like "administrator = 1", <tt>[ "user_name = ?", username ]</tt>, or <tt>["user_name = :user_name", { :user_name => user_name }]</tt>. See conditions in the intro. + # * <tt>:order</tt> - An SQL fragment like "created_at DESC, name". + # * <tt>:group</tt> - An attribute name by which the result should be grouped. Uses the <tt>GROUP BY</tt> SQL-clause. + # * <tt>:having</tt> - Combined with +:group+ this can be used to filter the records that a <tt>GROUP BY</tt> returns. Uses the <tt>HAVING</tt> SQL-clause. + # * <tt>:limit</tt> - An integer determining the limit on the number of rows that should be returned. + # * <tt>:offset</tt> - An integer determining the offset from where the rows should be fetched. So at 5, it would skip rows 0 through 4. + # * <tt>:joins</tt> - Either an SQL fragment for additional joins like "LEFT JOIN comments ON comments.post_id = id" (rarely needed), + # named associations in the same form used for the <tt>:include</tt> option, which will perform an <tt>INNER JOIN</tt> on the associated table(s), + # or an array containing a mixture of both strings and named associations. + # If the value is a string, then the records will be returned read-only since they will have attributes that do not correspond to the table's columns. + # Pass <tt>:readonly => false</tt> to override. + # * <tt>:include</tt> - Names associations that should be loaded alongside. The symbols named refer + # to already defined associations. See eager loading under Associations. + # * <tt>:select</tt> - By default, this is "*" as in "SELECT * FROM", but can be changed if you, for example, want to do a join but not + # include the joined columns. Takes a string with the SELECT SQL fragment (e.g. "id, name"). + # * <tt>:from</tt> - By default, this is the table name of the class, but can be changed to an alternate table name (or even the name + # of a database view). + # * <tt>:readonly</tt> - Mark the returned records read-only so they cannot be saved or updated. + # * <tt>:lock</tt> - An SQL fragment like "FOR UPDATE" or "LOCK IN SHARE MODE". + # <tt>:lock => true</tt> gives connection's default exclusive lock, usually "FOR UPDATE". + # + # ==== Examples + # + # # find by id + # Person.find(1) # returns the object for ID = 1 + # Person.find(1, 2, 6) # returns an array for objects with IDs in (1, 2, 6) + # Person.find([7, 17]) # returns an array for objects with IDs in (7, 17) + # Person.find([1]) # returns an array for the object with ID = 1 + # Person.find(1, :conditions => "administrator = 1", :order => "created_on DESC") + # + # Note that returned records may not be in the same order as the ids you + # provide since database rows are unordered. Give an explicit <tt>:order</tt> + # to ensure the results are sorted. + # + # ==== Examples + # + # # find first + # Person.find(:first) # returns the first object fetched by SELECT * FROM people + # Person.find(:first, :conditions => [ "user_name = ?", user_name]) + # Person.find(:first, :conditions => [ "user_name = :u", { :u => user_name }]) + # Person.find(:first, :order => "created_on DESC", :offset => 5) + # + # # find last + # Person.find(:last) # returns the last object fetched by SELECT * FROM people + # Person.find(:last, :conditions => [ "user_name = ?", user_name]) + # Person.find(:last, :order => "created_on DESC", :offset => 5) + # + # # find all + # Person.find(:all) # returns an array of objects for all the rows fetched by SELECT * FROM people + # Person.find(:all, :conditions => [ "category IN (?)", categories], :limit => 50) + # Person.find(:all, :conditions => { :friends => ["Bob", "Steve", "Fred"] } + # Person.find(:all, :offset => 10, :limit => 10) + # Person.find(:all, :include => [ :account, :friends ]) + # Person.find(:all, :group => "category") + # + # Example for find with a lock: Imagine two concurrent transactions: + # each will read <tt>person.visits == 2</tt>, add 1 to it, and save, resulting + # in two saves of <tt>person.visits = 3</tt>. By locking the row, the second + # transaction has to wait until the first is finished; we get the + # expected <tt>person.visits == 4</tt>. + # + # Person.transaction do + # person = Person.find(1, :lock => true) + # person.visits += 1 + # person.save! + # end + def find(*args, &block) return to_a.find(&block) if block_given? - expects_array = ids.first.kind_of?(Array) - return ids.first if expects_array && ids.first.empty? - - ids = ids.flatten.compact.uniq + options = args.extract_options! - case ids.size - when 0 - raise RecordNotFound, "Couldn't find #{@klass.name} without an ID" - when 1 - result = find_one(ids.first) - expects_array ? [ result ] : result + if options.present? + apply_finder_options(options).find(*args) else - find_some(ids) + case args.first + when :first, :last, :all + send(args.first) + else + find_with_ids(*args) + end end end - def exists?(id = nil) - relation = select(primary_key).limit(1) - relation = relation.where(primary_key.eq(id)) if id - relation.first ? true : false + # A convenience wrapper for <tt>find(:first, *args)</tt>. You can pass in all the + # same arguments to this method as you can to <tt>find(:first)</tt>. + def first(*args) + args.any? ? apply_finder_options(args.first).first : find_first end - def first - if loaded? - @records.first - else - @first ||= limit(1).to_a[0] - end + # A convenience wrapper for <tt>find(:last, *args)</tt>. You can pass in all the + # same arguments to this method as you can to <tt>find(:last)</tt>. + def last(*args) + args.any? ? apply_finder_options(args.first).last : find_last end - def last - if loaded? - @records.last + # A convenience wrapper for <tt>find(:all, *args)</tt>. You can pass in all the + # same arguments to this method as you can to <tt>find(:all)</tt>. + def all(*args) + args.any? ? apply_finder_options(args.first).to_a : to_a + end + + # Returns true if a record exists in the table that matches the +id+ or + # conditions given, or false otherwise. The argument can take five forms: + # + # * Integer - Finds the record with this primary key. + # * String - Finds the record with a primary key corresponding to this + # string (such as <tt>'5'</tt>). + # * Array - Finds the record that matches these +find+-style conditions + # (such as <tt>['color = ?', 'red']</tt>). + # * Hash - Finds the record that matches these +find+-style conditions + # (such as <tt>{:color => 'red'}</tt>). + # * No args - Returns false if the table is empty, true otherwise. + # + # For more information about specifying conditions as a Hash or Array, + # see the Conditions section in the introduction to ActiveRecord::Base. + # + # Note: You can't pass in a condition as a string (like <tt>name = + # 'Jamie'</tt>), since it would be sanitized and then queried against + # the primary key column, like <tt>id = 'name = \'Jamie\''</tt>. + # + # ==== Examples + # Person.exists?(5) + # Person.exists?('5') + # Person.exists?(:name => "David") + # Person.exists?(['name LIKE ?', "%#{query}%"]) + # Person.exists? + def exists?(id = nil) + case id + when Array, Hash + where(id).exists? else - @last ||= reverse_order.limit(1).to_a[0] + relation = select(primary_key).limit(1) + relation = relation.where(primary_key.eq(id)) if id + relation.first ? true : false end end @@ -53,9 +166,20 @@ module ActiveRecord [] end + def construct_relation_for_association_calculations + including = (@eager_load_values + @includes_values).uniq + join_dependency = ActiveRecord::Associations::ClassMethods::JoinDependency.new(@klass, including, arel.joins(arel)) + + relation = except(:includes, :eager_load, :preload) + apply_join_dependency(relation, join_dependency) + end + def construct_relation_for_association_find(join_dependency) relation = except(:includes, :eager_load, :preload, :select).select(@klass.send(:column_aliases, join_dependency)) + apply_join_dependency(relation, join_dependency) + end + def apply_join_dependency(relation, join_dependency) for association in join_dependency.join_associations relation = association.join_relation(relation) end @@ -113,11 +237,30 @@ module ActiveRecord record end + def find_with_ids(*ids, &block) + return to_a.find(&block) if block_given? + + expects_array = ids.first.kind_of?(Array) + return ids.first if expects_array && ids.first.empty? + + ids = ids.flatten.compact.uniq + + case ids.size + when 0 + raise RecordNotFound, "Couldn't find #{@klass.name} without an ID" + when 1 + result = find_one(ids.first) + expects_array ? [ result ] : result + else + find_some(ids) + end + end + def find_one(id) record = where(primary_key.eq(id)).first unless record - conditions = where_clause(', ') + conditions = arel.send(:where_clauses).join(', ') conditions = " [WHERE #{conditions}]" if conditions.present? raise RecordNotFound, "Couldn't find #{@klass.name} with ID=#{id}#{conditions}" end @@ -129,21 +272,21 @@ module ActiveRecord result = where(primary_key.in(ids)).all expected_size = - if arel.taken && ids.size > arel.taken - arel.taken + if @limit_value && ids.size > @limit_value + @limit_value else ids.size end # 11 ids with limit 3, offset 9 should give 2 results. - if arel.skipped && (ids.size - arel.skipped < expected_size) - expected_size = ids.size - arel.skipped + if @offset_value && (ids.size - @offset_value < expected_size) + expected_size = ids.size - @offset_value end if result.size == expected_size result else - conditions = where_clause(', ') + conditions = arel.send(:where_clauses).join(', ') conditions = " [WHERE #{conditions}]" if conditions.present? error = "Couldn't find all #{@klass.name.pluralize} with IDs " @@ -152,5 +295,21 @@ module ActiveRecord end end + def find_first + if loaded? + @records.first + else + @first ||= limit(1).to_a[0] + end + end + + def find_last + if loaded? + @records.last + else + @last ||= reverse_order.limit(1).to_a[0] + end + end + end end diff --git a/activerecord/lib/active_record/relation/query_methods.rb b/activerecord/lib/active_record/relation/query_methods.rb index a3ac58bc81..8954f2d12b 100644 --- a/activerecord/lib/active_record/relation/query_methods.rb +++ b/activerecord/lib/active_record/relation/query_methods.rb @@ -8,11 +8,10 @@ module ActiveRecord class_eval <<-CEVAL def #{query_method}(*args) - spawn.tap do |new_relation| - new_relation.#{query_method}_values ||= [] - value = Array.wrap(args.flatten).reject {|x| x.blank? } - new_relation.#{query_method}_values += value if value.present? - end + new_relation = spawn + value = Array.wrap(args.flatten).reject {|x| x.blank? } + new_relation.#{query_method}_values += value if value.present? + new_relation end CEVAL end @@ -20,11 +19,10 @@ module ActiveRecord [:where, :having].each do |query_method| class_eval <<-CEVAL def #{query_method}(*args) - spawn.tap do |new_relation| - new_relation.#{query_method}_values ||= [] - value = build_where(*args) - new_relation.#{query_method}_values += [*value] if value.present? - end + new_relation = spawn + value = build_where(*args) + new_relation.#{query_method}_values += [*value] if value.present? + new_relation end CEVAL end @@ -34,9 +32,9 @@ module ActiveRecord class_eval <<-CEVAL def #{query_method}(value = true) - spawn.tap do |new_relation| - new_relation.#{query_method}_value = value - end + new_relation = spawn + new_relation.#{query_method}_value = value + new_relation end CEVAL end @@ -77,7 +75,7 @@ module ActiveRecord # Build association joins first joins.each do |join| - association_joins << join if [Hash, Array, Symbol].include?(join.class) && !@klass.send(:array_of_strings?, join) + association_joins << join if [Hash, Array, Symbol].include?(join.class) && !array_of_strings?(join) end if association_joins.any? @@ -110,7 +108,7 @@ module ActiveRecord when Relation::JoinOperation arel = arel.join(join.relation, join.join_class).on(*join.on) when Hash, Array, Symbol - if @klass.send(:array_of_strings?, join) + if array_of_strings?(join) join_string = join.join(' ') arel = arel.join(join_string) end @@ -119,8 +117,16 @@ module ActiveRecord end end - @where_values.uniq.each do |w| - arel = w.is_a?(String) ? arel.where(w) : arel.where(*w) + @where_values.uniq.each do |where| + next if where.blank? + + case where + when Arel::SqlLiteral + arel = arel.where(where) + else + sql = where.is_a?(String) ? where : where.to_sql + arel = arel.where(Arel::SqlLiteral.new("(#{sql})")) + end end @having_values.uniq.each do |h| @@ -135,21 +141,23 @@ module ActiveRecord end @order_values.uniq.each do |o| - arel = arel.order(o) if o.present? + arel = arel.order(Arel::SqlLiteral.new(o.to_s)) if o.present? end selects = @select_values.uniq + quoted_table_name = @klass.quoted_table_name + if selects.present? selects.each do |s| @implicit_readonly = false arel = arel.project(s) if s.present? end - elsif joins.present? - arel = arel.project(@klass.quoted_table_name + '.*') + else + arel = arel.project(quoted_table_name + '.*') end - arel = arel.from(@from_value) if @from_value.present? + arel = @from_value.present? ? arel.from(@from_value) : arel.from(quoted_table_name) case @lock_value when TrueClass @@ -167,8 +175,7 @@ module ActiveRecord builder = PredicateBuilder.new(table.engine) conditions = if [String, Array].include?(args.first.class) - merged = @klass.send(:merge_conditions, args.size > 1 ? Array.wrap(args) : args.first) - Arel::SqlLiteral.new(merged) if merged + @klass.send(:sanitize_sql, args.size > 1 ? args : args.first) elsif args.first.is_a?(Hash) attributes = @klass.send(:expand_hash_conditions_for_aggregates, args.first) builder.build_from_hash(attributes, table) @@ -193,5 +200,9 @@ module ActiveRecord }.join(',') end + def array_of_strings?(o) + o.is_a?(Array) && o.all?{|obj| obj.is_a?(String)} + end + end end diff --git a/activerecord/lib/active_record/relation/spawn_methods.rb b/activerecord/lib/active_record/relation/spawn_methods.rb index d5b13c6100..cccf413e67 100644 --- a/activerecord/lib/active_record/relation/spawn_methods.rb +++ b/activerecord/lib/active_record/relation/spawn_methods.rb @@ -1,17 +1,7 @@ module ActiveRecord module SpawnMethods - def spawn(arel_table = self.table) - relation = self.class.new(@klass, arel_table) - - (Relation::ASSOCIATION_METHODS + Relation::MULTI_VALUE_METHODS).each do |query_method| - relation.send(:"#{query_method}_values=", send(:"#{query_method}_values")) - end - - Relation::SINGLE_VALUE_METHODS.each do |query_method| - relation.send(:"#{query_method}_value=", send(:"#{query_method}_value")) - end - - relation + def spawn + clone.reset end def merge(r) @@ -98,19 +88,12 @@ module ActiveRecord options.assert_valid_keys(VALID_FIND_OPTIONS) - relation = relation.joins(options[:joins]). - where(options[:conditions]). - select(options[:select]). - group(options[:group]). - having(options[:having]). - order(options[:order]). - limit(options[:limit]). - offset(options[:offset]). - from(options[:from]). - includes(options[:include]) - - relation = relation.lock(options[:lock]) if options[:lock].present? - relation = relation.readonly(options[:readonly]) if options.has_key?(:readonly) + [:joins, :select, :group, :having, :order, :limit, :offset, :from, :lock, :readonly].each do |finder| + relation = relation.send(finder, options[finder]) if options.has_key?(finder) + end + + relation = relation.where(options[:conditions]) if options.has_key?(:conditions) + relation = relation.includes(options[:include]) if options.has_key?(:include) relation end |