From 9465b84b543ae1ada29c0e39e34f919c724eab6d Mon Sep 17 00:00:00 2001 From: Pratik Naik Date: Tue, 19 Jan 2010 22:15:35 +0530 Subject: Rename CalculationMethods to Calculations and get rid of the old Calculations module --- activerecord/lib/active_record.rb | 3 +- activerecord/lib/active_record/base.rb | 3 +- activerecord/lib/active_record/calculations.rb | 9 - activerecord/lib/active_record/relation.rb | 2 +- .../active_record/relation/calculation_methods.rb | 258 --------------------- .../lib/active_record/relation/calculations.rb | 258 +++++++++++++++++++++ 6 files changed, 262 insertions(+), 271 deletions(-) delete mode 100644 activerecord/lib/active_record/calculations.rb delete mode 100644 activerecord/lib/active_record/relation/calculation_methods.rb create mode 100644 activerecord/lib/active_record/relation/calculations.rb (limited to 'activerecord/lib') diff --git a/activerecord/lib/active_record.rb b/activerecord/lib/active_record.rb index d5b6d40514..58673ab7bd 100644 --- a/activerecord/lib/active_record.rb +++ b/activerecord/lib/active_record.rb @@ -53,14 +53,13 @@ module ActiveRecord autoload_under 'relation' do autoload :QueryMethods autoload :FinderMethods - autoload :CalculationMethods + autoload :Calculations autoload :PredicateBuilder autoload :SpawnMethods end autoload :Base autoload :Batches - autoload :Calculations autoload :Callbacks autoload :DynamicFinderMatch autoload :DynamicScopeMatch diff --git a/activerecord/lib/active_record/base.rb b/activerecord/lib/active_record/base.rb index 06244d1132..e10df1abd3 100755 --- a/activerecord/lib/active_record/base.rb +++ b/activerecord/lib/active_record/base.rb @@ -654,6 +654,7 @@ module ActiveRecord #:nodoc: end delegate :select, :group, :order, :limit, :joins, :where, :preload, :eager_load, :includes, :from, :lock, :readonly, :having, :to => :scoped + delegate :count, :average, :minimum, :maximum, :sum, :calculate, :to => :scoped # A convenience wrapper for find(:first, *args). You can pass in all the # same arguments to this method as you can to find(:first). @@ -2742,7 +2743,7 @@ module ActiveRecord #:nodoc: # #save_with_autosave_associations to be wrapped inside a transaction. include AutosaveAssociation, NestedAttributes - include Aggregations, Transactions, Reflection, Batches, Calculations, Serialization + include Aggregations, Transactions, Reflection, Batches, Serialization end end diff --git a/activerecord/lib/active_record/calculations.rb b/activerecord/lib/active_record/calculations.rb deleted file mode 100644 index ea63617c52..0000000000 --- a/activerecord/lib/active_record/calculations.rb +++ /dev/null @@ -1,9 +0,0 @@ -module ActiveRecord - module Calculations #:nodoc: - extend ActiveSupport::Concern - - module ClassMethods - delegate :count, :average, :minimum, :maximum, :sum, :calculate, :to => :scoped - end - end -end diff --git a/activerecord/lib/active_record/relation.rb b/activerecord/lib/active_record/relation.rb index 19f91f4278..6ac7137976 100644 --- a/activerecord/lib/active_record/relation.rb +++ b/activerecord/lib/active_record/relation.rb @@ -5,7 +5,7 @@ module ActiveRecord MULTI_VALUE_METHODS = [:select, :group, :order, :joins, :where, :having] SINGLE_VALUE_METHODS = [:limit, :offset, :lock, :readonly, :create_with, :from] - include FinderMethods, CalculationMethods, SpawnMethods, QueryMethods + include FinderMethods, Calculations, SpawnMethods, QueryMethods delegate :length, :collect, :map, :each, :all?, :include?, :to => :to_a 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 155e90333c..0000000000 --- a/activerecord/lib/active_record/relation/calculation_methods.rb +++ /dev/null @@ -1,258 +0,0 @@ -module ActiveRecord - module CalculationMethods - # 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: - # - # * :conditions: An SQL fragment like "administrator = 1" or [ "user_name = ?", username ]. See conditions in the intro to ActiveRecord::Base. - # * :joins: 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 :include 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 :readonly => false to override. - # * :include: 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. - # * :order: An SQL fragment like "created_at DESC, name" (really only used with GROUP BY calculations). - # * :group: An attribute name by which the result should be grouped. Uses the GROUP BY SQL-clause. - # * :select: 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. - # * :distinct: Set this to true to make this a distinct calculation, such as SELECT COUNT(DISTINCT posts.id) ... - # * :from - 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: Person.count(:all) will not work because it will use :all 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 :conditions, :order, :group, :having, and :joins 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 :group 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: - # * :conditions - An SQL fragment like "administrator = 1" or [ "user_name = ?", username ]. See conditions in the intro to ActiveRecord::Base. - # * :include: 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. - # * :joins - 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. - # * :order - An SQL fragment like "created_at DESC, name" (really only used with GROUP BY calculations). - # * :group - An attribute name by which the result should be grouped. Uses the GROUP BY SQL-clause. - # * :select - 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. - # * :distinct - 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 - - 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 - - # 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/calculations.rb b/activerecord/lib/active_record/relation/calculations.rb new file mode 100644 index 0000000000..5645e7f031 --- /dev/null +++ b/activerecord/lib/active_record/relation/calculations.rb @@ -0,0 +1,258 @@ +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: + # + # * :conditions: An SQL fragment like "administrator = 1" or [ "user_name = ?", username ]. See conditions in the intro to ActiveRecord::Base. + # * :joins: 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 :include 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 :readonly => false to override. + # * :include: 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. + # * :order: An SQL fragment like "created_at DESC, name" (really only used with GROUP BY calculations). + # * :group: An attribute name by which the result should be grouped. Uses the GROUP BY SQL-clause. + # * :select: 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. + # * :distinct: Set this to true to make this a distinct calculation, such as SELECT COUNT(DISTINCT posts.id) ... + # * :from - 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: Person.count(:all) will not work because it will use :all 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 :conditions, :order, :group, :having, and :joins 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 :group 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: + # * :conditions - An SQL fragment like "administrator = 1" or [ "user_name = ?", username ]. See conditions in the intro to ActiveRecord::Base. + # * :include: 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. + # * :joins - 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. + # * :order - An SQL fragment like "created_at DESC, name" (really only used with GROUP BY calculations). + # * :group - An attribute name by which the result should be grouped. Uses the GROUP BY SQL-clause. + # * :select - 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. + # * :distinct - 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 + + 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 + + # 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 -- cgit v1.2.3