use bind values for join columns

This is a backport of 4bc2ae0da1dd812aee759f6d13ad428354cd0e13.
It fixes bug #7950.

Conflicts:

	activerecord/lib/active_record/relation/calculations.rb
	activerecord/lib/active_record/relation/finder_methods.rb

activerecord/lib/active_record/associations/association_scope.rb

@@ -33,6 +33,18 @@ module ActiveRecord
 
       private
 
+      def column_for(table_name, column_name)
+        columns = alias_tracker.connection.schema_cache.columns_hash[table_name]
+        columns[column_name]
+      end
+
+      def bind(scope, column, value)
+        substitute = alias_tracker.connection.substitute_at(
+          column, scope.bind_values.length)
+        scope.bind_values += [[column, value]]
+        substitute
+      end
+
       def add_constraints(scope)
         tables = construct_tables
 
@@ -67,7 +79,10 @@ module ActiveRecord
           conditions = self.conditions[i]
 
           if reflection == chain.last
-            scope = scope.where(table[key].eq(owner[foreign_key]))
+            column = column_for(table.table_name, key.to_s)
+            bind_val = bind(scope, column, owner[foreign_key])
+            scope = scope.where(table[key].eq(bind_val))
+            #scope = scope.where(table[key].eq(owner[foreign_key]))
 
             if reflection.type
               scope = scope.where(table[reflection.type].eq(owner.class.base_class.name))

activerecord/lib/active_record/connection_adapters/abstract/database_statements.rb

@@ -20,14 +20,14 @@ module ActiveRecord
 
       # Returns a record hash with the column names as keys and column values
       # as values.
-      def select_one(arel, name = nil)
-        result = select_all(arel, name)
+      def select_one(arel, name = nil, binds = [])
+        result = select_all(arel, name, binds)
         result.first if result
       end
 
       # Returns a single value from a record
-      def select_value(arel, name = nil)
-        if result = select_one(arel, name)
+      def select_value(arel, name = nil, binds = [])
+        if result = select_one(arel, name, binds)
           result.values.first
         end
       end

activerecord/lib/active_record/relation.rb

@@ -464,7 +464,12 @@ module ActiveRecord
         node.left.relation.name == table_name
       }
 
-      Hash[equalities.map { |where| [where.left.name, where.right] }]
+      binds = Hash[bind_values.find_all(&:first).map { |column, v| [column.name, v] }]
+
+      Hash[equalities.map { |where|
+        name = where.left.name
+        [name, binds.fetch(name.to_s) { where.right }]
+      }]
     end
 
     def scope_for_create

activerecord/lib/active_record/relation/calculations.rb

@@ -178,7 +178,7 @@ module ActiveRecord
     #
     def pluck(column_name)
       column_name = column_name.to_s
-      klass.connection.select_all(select(column_name).arel).map! do |attributes|
+      klass.connection.select_all(select(column_name).arel, nil, bind_values).map! do |attributes|
         klass.type_cast_attribute(attributes.keys.first, klass.initialize_attributes(attributes))
       end
     end
@@ -240,7 +240,8 @@ module ActiveRecord
         query_builder = relation.arel
       end
 
-      type_cast_calculated_value(@klass.connection.select_value(query_builder), column_for(column_name), operation)
+      result = @klass.connection.select_value(query_builder, nil, relation.bind_values)
+      type_cast_calculated_value(result, column_for(column_name), operation)
     end
 
     def execute_grouped_calculation(operation, column_name, distinct) #:nodoc:
@@ -286,7 +287,7 @@ module ActiveRecord
       relation = except(:group).group(group)
       relation.select_values = select_values
 
-      calculated_data = @klass.connection.select_all(relation)
+      calculated_data = @klass.connection.select_all(relation, nil, bind_values)
 
       if association
         key_ids     = calculated_data.collect { |row| row[group_aliases.first] }

activerecord/lib/active_record/relation/finder_methods.rb

@@ -199,7 +199,7 @@ module ActiveRecord
         relation = relation.where(table[primary_key].eq(id)) if id
       end
 
-      connection.select_value(relation, "#{name} Exists") ? true : false
+      connection.select_value(relation, "#{name} Exists", relation.bind_values) ? true : false
     rescue ThrowResult
       false
     end
@@ -332,7 +332,7 @@ module ActiveRecord
 
       substitute = connection.substitute_at(column, @bind_values.length)
       relation = where(table[primary_key].eq(substitute))
-      relation.bind_values = [[column, id]]
+      relation.bind_values += [[column, id]]
       record = relation.first
 
       unless record

activerecord/lib/active_record/relation/spawn_methods.rb

@@ -22,7 +22,7 @@ module ActiveRecord
         end
       end
 
-      (Relation::MULTI_VALUE_METHODS - [:joins, :where, :order]).each do |method|
+      (Relation::MULTI_VALUE_METHODS - [:joins, :where, :order, :binds]).each do |method|
         value = r.send(:"#{method}_values")
         merged_relation.send(:"#{method}_values=", merged_relation.send(:"#{method}_values") + value) if value.present?
       end
@@ -31,6 +31,8 @@ module ActiveRecord
 
       merged_wheres = @where_values + r.where_values
 
+      merged_binds = (@bind_values + r.bind_values).uniq(&:first)
+
       unless @where_values.empty?
         # Remove duplicates, last one wins.
         seen = Hash.new { |h,table| h[table] = {} }
@@ -47,6 +49,7 @@ module ActiveRecord
       end
 
       merged_relation.where_values = merged_wheres
+      merged_relation.bind_values = merged_binds
 
       (Relation::SINGLE_VALUE_METHODS - [:lock, :create_with, :reordering]).each do |method|
         value = r.send(:"#{method}_value")