diff options
Diffstat (limited to 'activerecord/lib/active_record/relation/calculations.rb')
| -rw-r--r-- | activerecord/lib/active_record/relation/calculations.rb | 52 |
1 files changed, 26 insertions, 26 deletions
diff --git a/activerecord/lib/active_record/relation/calculations.rb b/activerecord/lib/active_record/relation/calculations.rb index a679c444cf..64edcc1ef3 100644 --- a/activerecord/lib/active_record/relation/calculations.rb +++ b/activerecord/lib/active_record/relation/calculations.rb @@ -6,32 +6,32 @@ 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 + # * 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 ]. + # * <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 + # 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 + # 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 + # * <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, + # * <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 + # * <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 + # * <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: @@ -44,16 +44,16 @@ module ActiveRecord # 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) + # 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(: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. + # 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) @@ -95,14 +95,14 @@ 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 <tt>:conditions</tt>, + # 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 + # * 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 + # * 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') @@ -119,29 +119,29 @@ module ActiveRecord # end # # Options: - # * <tt>:conditions</tt> - An SQL fragment like "administrator = 1" or [ "user_name = ?", username ]. + # * <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, + # * <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". + # * <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 + # 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 + # * <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 + # * <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 + # 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.minimum(:age, :having => 'min(age) > 17', :group => :last_name) # # Person.sum("2 * age") def calculate(operation, column_name, options = {}) @@ -282,7 +282,7 @@ module ActiveRecord def select_for_count if @select_values.present? - select = @select_values.join(", ") + select = @select_values.join(", ") select if select !~ /(,|\*)/ end end |