X-Git-Url: https://git.njae.me.uk/?a=blobdiff_plain;ds=sidebyside;f=vendor%2Frails%2Factiverecord%2Flib%2Factive_record%2Fcalculations.rb;fp=vendor%2Frails%2Factiverecord%2Flib%2Factive_record%2Fcalculations.rb;h=0000000000000000000000000000000000000000;hb=36d9f3351a3b4e8159279445190e2287ffdea86c;hp=f077818d3b4dcb8c8f88b189013c5fc9140be9cc;hpb=913cf6054b1d29b5d2f5e620304af7ee77cc1f1f;p=feedcatcher.git diff --git a/vendor/rails/activerecord/lib/active_record/calculations.rb b/vendor/rails/activerecord/lib/active_record/calculations.rb deleted file mode 100644 index f077818..0000000 --- a/vendor/rails/activerecord/lib/active_record/calculations.rb +++ /dev/null @@ -1,317 +0,0 @@ -module ActiveRecord - module Calculations #:nodoc: - CALCULATIONS_OPTIONS = [:conditions, :joins, :order, :select, :group, :having, :distinct, :limit, :offset, :include, :from] - def self.included(base) - base.extend(ClassMethods) - end - - module ClassMethods - # 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(*args) - calculate(:count, *construct_count_options_from_args(*args)) - 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(:avg, 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(:min, 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(:max, 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 = {}) - validate_calculation_options(operation, options) - column_name = options[:select] if options[:select] - column_name = '*' if column_name == :all - column = column_for column_name - catch :invalid_query do - if options[:group] - return execute_grouped_calculation(operation, column_name, column, options) - else - return execute_simple_calculation(operation, column_name, column, options) - end - end - 0 - end - - protected - def construct_count_options_from_args(*args) - options = {} - column_name = :all - - # We need to handle - # count() - # count(:column_name=:all) - # count(options={}) - # count(column_name=:all, options={}) - # selects specified by scopes - case args.size - when 0 - column_name = scope(:find)[:select] if scope(:find) - when 1 - if args[0].is_a?(Hash) - column_name = scope(:find)[:select] if scope(:find) - 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 - - def construct_calculation_sql(operation, column_name, options) #:nodoc: - operation = operation.to_s.downcase - options = options.symbolize_keys - - scope = scope(:find) - merged_includes = merge_includes(scope ? scope[:include] : [], options[:include]) - aggregate_alias = column_alias_for(operation, column_name) - column_name = "#{connection.quote_table_name(table_name)}.#{column_name}" if column_names.include?(column_name.to_s) - - if operation == 'count' - if merged_includes.any? - options[:distinct] = true - column_name = options[:select] || [connection.quote_table_name(table_name), primary_key] * '.' - end - - if options[:distinct] - use_workaround = !connection.supports_count_distinct? - end - end - - if options[:distinct] && column_name.to_s !~ /\s*DISTINCT\s+/i - distinct = 'DISTINCT ' - end - sql = "SELECT #{operation}(#{distinct}#{column_name}) AS #{aggregate_alias}" - - # A (slower) workaround if we're using a backend, like sqlite, that doesn't support COUNT DISTINCT. - sql = "SELECT COUNT(*) AS #{aggregate_alias}" if use_workaround - - sql << ", #{options[:group_field]} AS #{options[:group_alias]}" if options[:group] - if options[:from] - sql << " FROM #{options[:from]} " - else - sql << " FROM (SELECT #{distinct}#{column_name}" if use_workaround - sql << " FROM #{connection.quote_table_name(table_name)} " - end - - joins = "" - add_joins!(joins, options[:joins], scope) - - if merged_includes.any? - join_dependency = ActiveRecord::Associations::ClassMethods::JoinDependency.new(self, merged_includes, joins) - sql << join_dependency.join_associations.collect{|join| join.association_join }.join - end - - sql << joins unless joins.blank? - - add_conditions!(sql, options[:conditions], scope) - add_limited_ids_condition!(sql, options, join_dependency) if join_dependency && !using_limitable_reflections?(join_dependency.reflections) && ((scope && scope[:limit]) || options[:limit]) - - if options[:group] - group_key = connection.adapter_name == 'FrontBase' ? :group_alias : :group_field - sql << " GROUP BY #{options[group_key]} " - end - - if options[:group] && options[:having] - having = sanitize_sql_for_conditions(options[:having]) - - # FrontBase requires identifiers in the HAVING clause and chokes on function calls - if connection.adapter_name == 'FrontBase' - having.downcase! - having.gsub!(/#{operation}\s*\(\s*#{column_name}\s*\)/, aggregate_alias) - end - - sql << " HAVING #{having} " - end - - sql << " ORDER BY #{options[:order]} " if options[:order] - add_limit!(sql, options, scope) - sql << ") #{aggregate_alias}_subquery" if use_workaround - sql - end - - def execute_simple_calculation(operation, column_name, column, options) #:nodoc: - value = connection.select_value(construct_calculation_sql(operation, column_name, options)) - type_cast_calculated_value(value, column, operation) - end - - def execute_grouped_calculation(operation, column_name, column, options) #:nodoc: - group_attr = options[:group].to_s - association = 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 - sql = construct_calculation_sql(operation, column_name, options.merge(:group_field => group_field, :group_alias => group_alias)) - calculated_data = connection.select_all(sql) - aggregate_alias = column_alias_for(operation, column_name) - - 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, operation) - all - end - end - - private - def validate_calculation_options(operation, options = {}) - options.assert_valid_keys(CALCULATIONS_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!(/ +/, '_') - - connection.table_alias_for(table_name) - end - - def column_for(field) - field_name = field.to_s.split('.').last - columns.detect { |c| c.name.to_s == field_name } - end - - def type_cast_calculated_value(value, column, operation = nil) - operation = operation.to_s.downcase - case operation - when 'count' then value.to_i - when 'sum' then type_cast_using_column(value || '0', column) - when 'avg' 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 - end - end -end