Merge pull request #5554 from alexanderreiff/use-pk-field-for-has-many-count

Use model.primaryKeyField for HasMany.count column

lib/associations/has-many.js

@@ -342,7 +342,7 @@ HasMany.prototype.count = function(instance, options) {
 
   options = association.target.__optClone(options) || {};
   options.attributes = [
-    [sequelize.fn('COUNT', sequelize.col(model.primaryKeyAttribute)), 'count']
+    [sequelize.fn('COUNT', sequelize.col(model.primaryKeyField)), 'count']
   ];
   options.raw = true;
   options.plain = true;