Optimized the SQL used to generate has_and_belongs_to_many queries by listing the join table first #693 [yerejm]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@741 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activerecord/CHANGELOG

@@ -1,5 +1,7 @@
 *SVN*
 
+* Optimized the SQL used to generate has_and_belongs_to_many queries by listing the join table first #693 [yerejm]
+
 * Fixed that when using validation macros with a custom message, if you happened to use single quotes in the message string you would get a parsing error #657 [tonka]
 
 * Fixed that Active Record would throw Broken Pipe errors with FCGI when the MySQL connection timed out instead of reconnecting #428 [Nicholas Seckar]

activerecord/lib/active_record/associations/has_and_belongs_to_many_association.rb

@@ -147,7 +147,7 @@ module ActiveRecord
         def construct_sql
           interpolate_sql_options!(@options, :finder_sql, :delete_sql)
           @finder_sql = @options[:finder_sql] ||
-                "SELECT t.*, j.* FROM #{@association_table_name} t, #{@join_table} j " +
+                "SELECT t.*, j.* FROM #{@join_table} j, #{@association_table_name} t " +
                 "WHERE t.#{@association_class.primary_key} = j.#{@association_foreign_key} AND " +
                 "j.#{@association_class_primary_key_name} = #{@owner.quoted_id} " +
                 (@options[:conditions] ? " AND " + interpolate_sql(@options[:conditions]) : "") + " " +

activerecord/lib/active_record/base.rb

@@ -144,7 +144,7 @@ module ActiveRecord #:nodoc:
   #   class Client < Company; end
   #   class PriorityClient < Client; end
   #
-  # When you do Firm.create("name" => "37signals"), this record with be saved in the companies table with type = "Firm". You can then
+  # When you do Firm.create("name" => "37signals"), this record will be saved in the companies table with type = "Firm". You can then
   # fetch this row again using Company.find_first "name = '37signals'" and it will return a Firm object.
   #
   # If you don't have a type column defined in your table, single-table inheritance won't be triggered. In that case, it'll work just