将 Symfony 实体声明为 YAML
- appbundle /实体/ Person.php
 
<?php
namespace AppBundle\Entity;
/**
 * Person
 */
class Person
{
    /**
     * @var int
     */
    private $id;
    /**
     * @var string
     */
    private $name;
    /**
     * @var int
     */
    private $age;
    /**
     * Get id
     *
     * @return int
     */
    public function getId()
    {
        return $this->id;
    }
    /**
     * Set name
     *
     * @param string $name
     *
     * @return Person
     */
    public function setName($name)
    {
        $this->name = $name;
        return $this;
    }
    /**
     * Get name
     *
     * @return string
     */
    public function getName()
    {
        return $this->name;
    }
    /**
     * Set age
     *
     * @param integer $age
     *
     * @return Person
     */
    public function setAge($age)
    {
        $this->age = $age;
        return $this;
    }
    /**
     * Get age
     *
     * @return int
     */
    public function getAge()
    {
        return $this->age;
    }
}
- appbundle /资源/配置/教义/ Person.orm.yml
 
AppBundle\Entity\Person:
    type: entity
    repositoryClass: AppBundle\Repository\PersonRepository
    table: persons
    id:
        id:
            type: integer
            id: true
            generator:
                strategy: AUTO
    fields:
        name:
            type: string
            length: 20
            nullable: false
            column: Name
            unique: true
        age:
            type: integer
            nullable: false
            column: Age
            unique: false
    lifecycleCallbacks: { }
- 创建表
 
php bin/console doctrine:schema:update --force
或者使用推荐的方式(假设你已在项目中安装了 doctrine-migrations-bundle):
php bin/console doctrine:migrations:diff
php bin/console doctrine:migrations:migrate
- 
从 YAML 自动创建实体
php bin / console doctrine:generate:entities AppBundle