From 1ce40ca56216ae76e93cde78ec2752de110400c0 Mon Sep 17 00:00:00 2001 From: Neeraj Singh Date: Mon, 2 Aug 2010 12:25:26 -0400 Subject: ensuring that description does not exceed 100 columns --- .../lib/active_record/relation/calculations.rb | 79 ++++++++++++++-------- .../lib/active_record/relation/finder_methods.rb | 23 ++++--- 2 files changed, 66 insertions(+), 36 deletions(-) (limited to 'activerecord/lib/active_record/relation') diff --git a/activerecord/lib/active_record/relation/calculations.rb b/activerecord/lib/active_record/relation/calculations.rb index 44baeb6c84..f8412bc604 100644 --- a/activerecord/lib/active_record/relation/calculations.rb +++ b/activerecord/lib/active_record/relation/calculations.rb @@ -5,26 +5,33 @@ module ActiveRecord # 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 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. + # * :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. + # 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. + # * :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 + # * :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). + # * :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 @@ -34,12 +41,19 @@ module ActiveRecord # # 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. + # + # # 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: Person.count(:all) will not work because it will use :all as the condition. Use Person.count instead. + # 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) @@ -80,13 +94,15 @@ module ActiveRecord 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. + # 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. + # * 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"] @@ -102,21 +118,30 @@ module ActiveRecord # 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. + # * :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) ... + # * :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.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.sum("2 * age") def calculate(operation, column_name, options = {}) if options.except(:distinct).present? diff --git a/activerecord/lib/active_record/relation/finder_methods.rb b/activerecord/lib/active_record/relation/finder_methods.rb index 3bf4c5bdd1..a192e044ea 100644 --- a/activerecord/lib/active_record/relation/finder_methods.rb +++ b/activerecord/lib/active_record/relation/finder_methods.rb @@ -21,23 +21,28 @@ module ActiveRecord # # ==== Parameters # - # * :conditions - An SQL fragment like "administrator = 1", [ "user_name = ?", username ], or ["user_name = :user_name", { :user_name => user_name }]. See conditions in the intro. + # * :conditions - An SQL fragment like "administrator = 1", [ "user_name = ?", username ], + # or ["user_name = :user_name", { :user_name => user_name }]. See conditions in the intro. # * :order - An SQL fragment like "created_at DESC, name". # * :group - An attribute name by which the result should be grouped. Uses the GROUP BY SQL-clause. - # * :having - Combined with +:group+ this can be used to filter the records that a GROUP BY returns. Uses the HAVING SQL-clause. + # * :having - Combined with +:group+ this can be used to filter the records that a + # GROUP BY returns. Uses the HAVING SQL-clause. # * :limit - An integer determining the limit on the number of rows that should be returned. - # * :offset - An integer determining the offset from where the rows should be fetched. So at 5, it would skip rows 0 through 4. + # * :offset - An integer determining the offset from where the rows should be fetched. So at 5, + # it would skip rows 0 through 4. # * :joins - 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 :include option, which will perform an INNER JOIN on the associated table(s), + # named associations in the same form used for the :include option, which will perform an + # INNER JOIN 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. + # 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 - Names associations that should be loaded alongside. The symbols named refer # to already defined associations. See eager loading under Associations. - # * :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. Takes a string with the SELECT SQL fragment (e.g. "id, name"). - # * :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). + # * :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. Takes a string with the SELECT SQL fragment (e.g. "id, name"). + # * :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). # * :readonly - Mark the returned records read-only so they cannot be saved or updated. # * :lock - An SQL fragment like "FOR UPDATE" or "LOCK IN SHARE MODE". # :lock => true gives connection's default exclusive lock, usually "FOR UPDATE". -- cgit v1.2.3