title: Auto increment id with sequelize in MySQL
body: <p>I have the following model in NodeJS with sequelize and a MySQL database:</p>
  
  <pre><code>var Sequelize = require('sequelize');
  var User = sequelize.define('user', {        
          id: {
              type: Sequelize.INTEGER,
              autoIncrement: true,
              primaryKey: true
          },
          ...
  };
  </code></pre>
  
  <p>I am trying to add a new user to my databse with the below code:</p>
  
  <pre><code>sequelize.transaction().then(function(t) {
          User.create({/* User data without id */}, {
              transaction: t
          }).then(function() {
              t.commit();
          }).catch(function(error) {
              t.rollback();
          });
      });
  </code></pre>
  
  <p>After that, I am getting the next error:</p>
  
  <pre><code>Executing (47f19f7b-a02d-4d72-ba7e-d5045520fffb): START TRANSACTION;
  Executing (47f19f7b-a02d-4d72-ba7e-d5045520fffb): SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ;
  Executing (47f19f7b-a02d-4d72-ba7e-d5045520fffb): SET autocommit = 1;
  Executing (47f19f7b-a02d-4d72-ba7e-d5045520fffb): INSERT INTO `user` (`id`, /* next fields */) VALUES (DEFAULT, /* next values */);
  Executing (47f19f7b-a02d-4d72-ba7e-d5045520fffb): ROLLBACK;
  </code></pre>
  
  <p>And the error message:</p>
  
  <pre><code>[SequelizeDatabaseError: ER_NO_DEFAULT_FOR_FIELD: Field 'id' doesn't have a default value]
    name: 'SequelizeDatabaseError',
    message: 'ER_NO_DEFAULT_FOR_FIELD: Field \'id\' doesn\'t have a default value'
  </code></pre>
  
  <p>However, if I manually set the id value, it works. It seems sequelize is trying to set a default value in the id field, instead setting an autoincrement integer. I have defined this field as autoIncrement in my database too. </p>
  
  <p>How could I do this insertion? Do I have to set the id manually?</p>
  
  <p><strong>EDIT</strong></p>
  
  <p>This is my table definition:</p>
  
  <pre><code>CREATE TABLE `user` (
    `id` int(11) NOT NULL AUTO_INCREMENT,
    `uid` varchar(9) NOT NULL,
    `name` varchar(20) NOT NULL,
    `email` varchar(30) DEFAULT NULL,
    `birthdate` date NOT NULL,
    PRIMARY KEY (`id`),
    UNIQUE KEY `uid_UNIQUE` (`uid`)
  ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
  </code></pre>