title: keyHolder.getKey() return null
body: <p>Why code from "Spring in action 5" don't work (keyHolder.getKey() return null, but entity is saved in DB)?</p>
  
  <pre><code>private long savePizzaInfo(Pizza pizza) {
      pizza.setCreatedAt(new Date());
      PreparedStatementCreator psc =
              new PreparedStatementCreatorFactory(
                      "insert into PIZZA (name, createdAt) values (?, ?)",
                      Types.VARCHAR, Types.TIMESTAMP
              ).newPreparedStatementCreator(
                      Arrays.asList(
                              pizza.getName(),
                              new Timestamp(pizza.getCreatedAt().getTime())));
      KeyHolder keyHolder = new GeneratedKeyHolder();
      template.update(psc, keyHolder);
      return keyHolder.getKey().longValue();
  }
  </code></pre>
  
  <p>My DB Table:</p>
  
  <pre><code>CREATE TABLE PIZZA
  (
  ID bigint DEFAULT (NEXT VALUE FOR 
  PUBLIC.SYSTEM_SEQUENCE_12CA966F_4FFD_469C_BA69_80BB93916EF3) AUTO_INCREMENT 
  PRIMARY KEY NOT NULL,
  NAME varchar(50) NOT NULL,
  CREATEDAT timestamp NOT NULL
  );
  CREATE UNIQUE INDEX PRIMARY_KEY_4 ON PIZZA (ID);
  </code></pre>