title: Sequelize TypeError: Cannot read property '1' of null
body: <p>Normally this type of error would not be a problem but i simply cannot understand where this is happening:</p>
  
  <p>Here is my setup:</p>
  
  <pre><code>router.route('/api/academyModule')
  .post(function (req, res) {
  
      req.body.academyModule.module_id = req.body.academyModule.module.id;
      req.body.academyModule.module_module_type_id = req.body.academyModule.module.module_type.id;
      var am = AcademyModule.build(req.body.academyModule);
      am.add(req.body.academyModule.requirements, req.body.academyModule, function (success) {
              res.json({id: this[null]});
  
          },
          function (err) {
              res.status(err).send(err);
          });
      if(req.body.teams != null)
      {
          req.body.teams.forEach(function(y)
          {
              var atm = academy_team_has_academy_module.build({academy_team_id: y.id, academy_id: y.academy_id, academy_module_module_id: req.body.academyModule.module_id })
              atm.add(function(success)
              {
  
              }, function(err)
              {
                  res.status(err).send(err);
              });
          });
      }
  })
  </code></pre>
  
  <p>For this i have the following model:</p>
  
  <pre><code>    academy_team_has_academy_module = sequelize.define('academy_team_has_academy_module', {
      academy_team_id: {
          type: DataTypes.INTEGER,
          primaryKey: true,
          autoIncrement: false
      },
      academy_id: DataTypes.INTEGER,
      academy_module_module_id: DataTypes.INTEGER
  }, {
      freezeTableName: true,
      instanceMethods: {
          add: function (onSuccess, onError) {
              academy_team_has_academy_module.build(this.dataValues)
                  .save().ok(onSuccess).error(onError);
          }
      }
  });
  </code></pre>
  
  <p>i know for sure this happens in this model and not <code>AcademyModule</code> because when i remove this code it runs without any issues. So in my console i get the following print out:</p>
  
  <pre><code>    Executing (default): INSERT INTO `requirements` (`id`,`value`,`requirement_type_id`) VALUES (DEFAULT,5,'2');
  Executing (default): INSERT INTO `academy_team_has_academy_module` (`academy_team_id`,`academy_id`,`academy_module_module_id`) VALUES (1,3,11);
  Executing (default): INSERT INTO `academy_module` (`academy_id`,`module_id`,`module_module_type_id`,`sort_number`,`requirements_id`) VALUES ('3',11,4,4,40);
  </code></pre>
  
  <p>And just right after i get:</p>
  
  <pre><code>    /var/www/learningbankapi/src/node_modules/mysql/lib/protocol/Parser.js:82
          throw err;
                ^
  TypeError: Cannot read property '1' of null
      at module.exports.Query.formatError (/var/www/learningbankapi/src/node_modules/sequelize/lib/dialects/mysql/query.js:155:23)
      at Query.module.exports.Query.run [as _callback] (/var/www/learningbankapi/src/node_modules/sequelize/lib/dialects/mysql/query.js:38:23)
      at Query.Sequence.end (/var/www/learningbankapi/src/node_modules/mysql/lib/protocol/sequences/Sequence.js:96:24)
      at Query.ErrorPacket (/var/www/learningbankapi/src/node_modules/mysql/lib/protocol/sequences/Query.js:93:8)
      at Protocol._parsePacket (/var/www/learningbankapi/src/node_modules/mysql/lib/protocol/Protocol.js:271:23)
      at Parser.write (/var/www/learningbankapi/src/node_modules/mysql/lib/protocol/Parser.js:77:12)
      at Protocol.write (/var/www/learningbankapi/src/node_modules/mysql/lib/protocol/Protocol.js:39:16)
      at Socket.Connection.connect (/var/www/learningbankapi/src/node_modules/mysql/lib/Connection.js:82:28)
      at Socket.EventEmitter.emit (events.js:95:17)
      at Socket.stream.pause.paused (_stream_readable.js:746:14)
      at Socket.EventEmitter.emit (events.js:92:17)
      at emitReadable_ (_stream_readable.js:408:10)
      at emitReadable (_stream_readable.js:404:5)
      at readableAddChunk (_stream_readable.js:165:9)
      at Socket.Readable.push (_stream_readable.js:127:10)
      at TCP.onread (net.js:526:21)
  </code></pre>
  
  <p>Ive debugged the whole thing and i can't seem to find any undefined variables. What might have gone wrong here?</p>