Question

我在nHibernate中遇到了批量大小的问题（C＃ - VS 2012）。我设置＆＃34;批量大小＆＃34;在集合和配置中，但它不起作用。

using (var s = OpenSession())
        {
            using (var t = s.BeginTransaction())
            {                   
                Parent parent = s.CreateCriteria(typeof(Parent)).List<Parent>().First();
                Console.Write(parent.Children[0]);
                t.Commit();
            }
        }

nHibernate探查器显示它一次性占用所有孩子（例如1000个孩子），但它应该只需要5个。

Parent.hbm.xml：

<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" namespace="L6.Model" assembly="L6">
  <class name="Parent">
    <id name="ParentId">
      <generator class="native" />
    </id>
    <bag name="Children" batch-size="5">
      <key column="ID_Parent"/>
      <one-to-many class="Child"/>
    </bag>
  </class>
</hibernate-mapping>

Child.hbm.xml：

<?xml version="1.0" encoding="utf-8" ?>
<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2" namespace="L6.Model" assembly="L6">
  <class name="Child">
    <id name="ChildId">
      <generator class="native" />
    </id>
    <many-to-one name="Parent" column="ID_Parent" class="Parent" />
  </class>
</hibernate-mapping>

的hibernate.cfg.xml

<?xml version="1.0" encoding="utf-8"?>
<!-- 
This template was written to work with NHibernate.Test.
Copy the template to your NHibernate.Test project folder and rename it in hibernate.cfg.xml and change it 
for your own use before compile tests in VisualStudio.
-->
<!-- This is the System.Data.dll provider for SQL Server -->
<hibernate-configuration xmlns="urn:nhibernate-configuration-2.2">
    <session-factory>
        <property name="connection.driver_class">NHibernate.Driver.SqlClientDriver</property>
        <property name="connection.connection_string">
            Server=.;initial catalog=Lista6;Integrated Security=SSPI
        </property>
    <property name="adonet.batch_size">5</property>
        <property name="show_sql">true</property>
        <property name="dialect">NHibernate.Dialect.MsSql2008Dialect</property>
        <property name="command_timeout">60</property>
        <property name="query.substitutions">true 1, false 0, yes 'Y', no 'N'</property>
    <property name="generate_statistics">true</property>
    <mapping file="Child.hbm.xml" />
    <mapping file="Parent.hbm.xml" />
  </session-factory>
</hibernate-configuration>

您是否有任何想法为什么批量大小不起作用？

Answer 1

你误解了batch-size的含义。

这意味着它会立即读取 5个孩子的收藏，而不是它会加载5个元素。

另一方面，

adonet.batch_size意味着插入/更新/删除语句将以该大小的组发送，以便减少往返次数。

nHibernate批量大小不起作用

1 个答案: