我们说有分类和产品表。产品已分配ID 并引用类别:
public class Product
{
public virtual int ProductId { get; set; }
public virtual Category Category { get; set; }
public virtual String Name { get; set; }
public Product() {}
public Product(int productId, string name, Category category) { ... }
}
插入三个这样的产品时:
var session = sessionFactory.OpenSession();
Product product = new Product(1, "New Product", session.Load<Category>(1));
session.Save(product);
session.Flush();
product = new Product(2, "New Product 2", session.Load<Category>(2));
session.Save(product);
session.Flush();
product = new Product(3, "New Product 3", session.Load<Category>(3));
session.Save(product);
session.Flush();
它只会生成三个插入(它不会获取类别)。
但是当在每次插入后执行相同的操作集而不刷新时,它将获取代理关联:
var session = sessionFactory.OpenSession();
Product product = new Product(1, "New Product", session.Load<Category>(1));
session.Save(product);
product = new Product(2, "New Product 2", session.Load<Category>(2));
session.Save(product);
product = new Product(3, "New Product 3", session.Load<Category>(3));
session.Save(product);
session.Flush();
生成的SQL如下:
这是一个非常简化的示例,实际上我需要插入大约1000个实体,并希望在不获取所有相关实体的情况下使用批处理。
更新:完整示例可以下载here