Don't try to select the primary key for models without primary key. Closes #4607

changelog.md

 # Next
 - [FIXED] Partial rollback of datatype validations by hiding it behind the `typeValidation` flag.
+- [FIXED] Don't try to select the primary key for models without primary key [#4607](https://github.com/sequelize/sequelize/issues/4607)
 
 # 3.11.0
 - [INTERNALS] Updated dependencies [#4594](https://github.com/sequelize/sequelize/pull/4594)

lib/model.js

@@ -1354,7 +1354,7 @@ Model.prototype.findAll = function(options) {
       validateIncludedElements.call(this, options, tableNames);
 
       // If we're not raw, we have to make sure we include the primary key for deduplication
-      if (!options.raw && options.attributes.indexOf(this.primaryKeyAttribute) === -1) {
+      if (options.attributes && !options.raw && this.primaryKeyAttribute &&  options.attributes.indexOf(this.primaryKeyAttribute) === -1) {
         options.originalAttributes = options.attributes;
         options.attributes = [this.primaryKeyAttribute].concat(options.attributes);
       }

test/unit/model/findall.test.js

@@ -68,6 +68,25 @@ describe(Support.getTestDialectTeaser('Model'), function() {
           ]);
         });
       });
+
+      it('works for models without PK #4607', function () {
+        var Model = current.define('model', {}, { timestamps: false });
+        var Foo = current.define('foo');
+        Model.hasOne(Foo);
+
+        Model.removeAttribute('id');
+
+        return Model.findAll({
+          attributes: {
+            include: ['name']
+          },
+          include: [Foo]
+        }).bind(this).then(function () {
+          expect(this.stub.getCall(0).args[2].attributes).to.deep.equal([
+            'name'
+          ]);
+        });
+      });
     });
   });
 });