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extract deprecated #calculate code

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1 parent d961f49 commit 5aea01a610c2ef7fa576d39d40a5a25bcb9f6ed4 @jonleighton jonleighton committed Apr 13, 2012
Showing with 25 additions and 83 deletions.
  1. +25 −83 activerecord/lib/active_record/relation/calculations.rb
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108 activerecord/lib/active_record/relation/calculations.rb
@@ -3,56 +3,19 @@
module ActiveRecord
module Calculations
- # Count operates using three different approaches.
+ # Count the records.
#
- # * 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.
+ # Person.count
+ # # => the total count of all people
#
- # The third approach, count using options, accepts an option hash as the only parameter. The options are:
+ # Person.count(:age)
+ # # => returns the total count of all people whose age is present in database
#
- # * <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).
+ # Person.count(:all)
+ # # => performs a COUNT(*) (:all is an alias for '*')
#
- # 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")
- #
- # # because of the named association, it finds the DISTINCT count using LEFT OUTER JOIN.
- # Person.count(:conditions => "age > 26 AND job.salary > 60000", :include => :job)
- #
- # # finds the number of rows matching the conditions and joins.
- # Person.count(:conditions => "age > 26 AND job.salary > 60000",
- # :joins => "LEFT JOIN jobs on jobs.person_id = person.id")
- #
- # 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.
+ # Person.count(:age, distinct: true)
+ # # => counts the number of different age values
def count(column_name = nil, options = {})
column_name, options = nil, column_name if column_name.is_a?(Hash)
calculate(:count, column_name, options)
@@ -98,69 +61,48 @@ def sum(*args)
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.
+ # minimum, and maximum have been added as shortcuts.
#
# 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')
+ # * Grouped values: This returns an ordered hash of the values and groups them. It
+ # takes either a column name, or the name of a belongs_to association.
+ #
+ # values = Person.group('last_name').maximum(:age)
# puts values["Drake"]
# => 43
#
# drake = Family.find_by_last_name('Drake')
- # values = Person.maximum(:age, :group => :family) # Person belongs_to :family
+ # values = Person.group(:family).maximum(:age) # 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'
#
# # Selects the minimum age for any family without any minors
- # Person.minimum(:age, :having => 'min(age) > 17', :group => :last_name)
+ # Person.group(:last_name).having("min(age) > 17").minimum(:age)
#
# 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
- relation = with_default_scope
-
- if relation.equal?(self)
- if eager_loading? || (includes_values.present? && references_eager_loaded_tables?)
- construct_relation_for_association_calculations.calculate(operation, column_name, options)
- else
- perform_calculation(operation, column_name, options)
- end
+ relation = with_default_scope
+
+ if relation.equal?(self)
+ if eager_loading? || (includes_values.present? && references_eager_loaded_tables?)
+ construct_relation_for_association_calculations.calculate(operation, column_name, options)
else
- relation.calculate(operation, column_name, options)
+ perform_calculation(operation, column_name, options)
end
+ else
+ relation.calculate(operation, column_name, options)
end
rescue ThrowResult
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