Added :count option to pagination that'll make it possible for the...

Added :count option to pagination that'll make it possible for the ActiveRecord::Base.count call to using something else than * for the count. Especially important for count queries using DISTINCT #3839 [skaes]. Added :select option to Base.count that'll allow you to select something else than * to be counted on. Especially important for count queries using DISTINCT (closes #3839) [skaes].

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@3620 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

actionpack/CHANGELOG

 *SVN*
 
+* Added :count option to pagination that'll make it possible for the ActiveRecord::Base.count call to using something else than * for the count. Especially important for count queries using DISTINCT #3839 [skaes]
+
 * Update script.aculo.us to V1.5.2 [Thomas Fuchs]
 
 * Added element and collection proxies to RJS [DHH]. Examples:

actionpack/lib/action_controller/pagination.rb

@@ -71,6 +71,7 @@ module Pagination
         :order      => nil,
         :join       => nil,
         :joins      => nil,
+        :count      => nil,
         :include    => nil,
         :select     => nil,
         :parameter  => 'page'
@@ -119,6 +120,10 @@ def self.validate_options!(collection_id, options, in_action) #:nodoc:
     #                        and Model.count
     # <tt>:include</tt>::    optional eager loading parameter passed to Model.find(:all, *params)
     #                        and Model.count
+    # <tt>:select</tt>::     :select parameter passed to Model.find(:all, *params)
+    #
+    # <tt>:count</tt>::      parameter passed as :select option to Model.count(*params)
+    #
     def paginate(collection_id, options={})
       Pagination.validate_options!(collection_id, options, true)
       paginator_and_collection_for(collection_id, options)
@@ -165,7 +170,9 @@ def create_paginators_and_retrieve_collections #:nodoc:
     # custom counter.
     def count_collection_for_pagination(model, options)
       model.count(:conditions => options[:conditions],
-                  :joins => options[:join] || options[:joins], :include => options[:include])
+                  :joins => options[:join] || options[:joins],
+                  :include => options[:include],
+                  :select => options[:count])
     end
     
     # Returns a collection of items for the given +model+ and +options[conditions]+,

actionpack/test/activerecord/pagination_test.rb

@@ -64,6 +64,14 @@ def paginate_with_join
                                              :conditions => 'project_id=1')        
       render :nothing => true
     end
+     
+    def paginate_with_join_and_count
+      @developer_pages, @developers = paginate(:developers, 
+                                             :join => 'd LEFT JOIN developers_projects ON d.id = developers_projects.developer_id',
+                                             :conditions => 'project_id=1',
+                                             :count => "d.id")        
+      render :nothing => true
+    end
     
     def rescue_errors(e) raise e end
 
@@ -133,9 +141,16 @@ def test_paginate_with_joins
   
   def test_paginate_with_join_and_conditions
     get :paginate_with_joins
-    expected = assigns(:topics)
+    expected = assigns(:developers)
     get :paginate_with_join
-    assert_equal expected, assigns(:topics)      
+    assert_equal expected, assigns(:developers)
+  end
+  
+  def test_paginate_with_join_and_count
+    get :paginate_with_joins
+    expected = assigns(:developers)
+    get :paginate_with_join_and_count
+    assert_equal expected, assigns(:developers)
   end
   
   def test_paginate_with_include_and_order

activerecord/CHANGELOG

 *SVN*
 
+* Added :select option to Base.count that'll allow you to select something else than * to be counted on. Especially important for count queries using DISTINCT #3839 [skaes]
+
 * Correct syntax error in mysql DDL,  and make AAACreateTablesTest run first [Bob Silva]
 
 * Allow :include to be used with has_many :through associations #3611 [Michael Schoen]

activerecord/lib/active_record/base.rb

@@ -544,7 +544,7 @@ def count(*args)
       def construct_counter_sql(options)
         sql  = "SELECT COUNT(" 
         sql << "DISTINCT " if options[:distinct]
-        sql << "#{table_name}.#{primary_key}) FROM #{table_name} "
+        sql << "#{options[:select] || "#{table_name}.#{primary_key}"}) FROM #{table_name} "
         sql << " #{options[:joins]} " if options[:joins]
         add_conditions!(sql, options[:conditions])
         sql

activerecord/test/base_test.rb

@@ -1050,19 +1050,39 @@ def test_set_inheritance_column_with_block
 
   def test_count_with_join
     res = Post.count_by_sql "SELECT COUNT(*) FROM posts LEFT JOIN comments ON posts.id=comments.post_id WHERE posts.#{QUOTED_TYPE} = 'Post'"
-    res2 = res + 1
+    res2 = nil
     assert_nothing_raised do
       res2 = Post.count("posts.#{QUOTED_TYPE} = 'Post'",
                         "LEFT JOIN comments ON posts.id=comments.post_id")
     end
     assert_equal res, res2
     
-    res3 = res + 1
+    res3 = nil
     assert_nothing_raised do
       res3 = Post.count(:conditions => "posts.#{QUOTED_TYPE} = 'Post'",
                         :joins => "LEFT JOIN comments ON posts.id=comments.post_id")
     end
     assert_equal res, res3
+    
+    res4 = Post.count_by_sql "SELECT COUNT(p.id) FROM posts p, comments c WHERE p.#{QUOTED_TYPE} = 'Post' AND p.id=c.post_id"
+    res5 = nil
+    assert_nothing_raised do
+      res5 = Post.count(:conditions => "p.#{QUOTED_TYPE} = 'Post' AND p.id=c.post_id",
+                        :joins => "p, comments c",
+                        :select => "p.id")
+    end
+
+    assert_equal res4, res5 
+    
+    res6 = Post.count_by_sql "SELECT COUNT(DISTINCT p.id) FROM posts p, comments c WHERE p.#{QUOTED_TYPE} = 'Post' AND p.id=c.post_id"
+    res7 = nil
+    assert_nothing_raised do
+      res7 = Post.count(:conditions => "p.#{QUOTED_TYPE} = 'Post' AND p.id=c.post_id",
+                        :joins => "p, comments c",
+                        :select => "p.id",
+                        :distinct => true)
+    end
+    assert_equal res6, res7
   end
   
   def test_clear_association_cache_stored