使用NHibernate出现错误"此SqlParameterCollection 的 Count=71 的索引 71 无效"

使用nhibernate做update操作时出现如下错误：

此 SqlParameterCollection 的 Count=71 的索引 71 无效。
XML文件

<?xml version="1.0" encoding="utf-8" ?>

<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2">

<class name="PERSON, Sgidi.Model" table="PERSON">

<id name="PNUMBER" type="String" unsaved-value="null">

<column name="PNUMBER" length="50" sql-type="varchar" not-null="true" unique="true" index="PK_PERSON_1"/>

<generator class="native" />

</id>

<property name="roomcode" type="String">

<column name="room_code" length="10" sql-type="varchar" not-null="true"/>

</property>

<many-to-one name="dept_info" class="dept_info" column="room_code" not-found="ignore"/>

</class>

</hibernate-mapping>

有两种解决方法

1.配置文件

<?xml version="1.0" encoding="utf-8" ?>

<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2">

<class name="PERSON, Sgidi.Model" table="PERSON">

<id name="PNUMBER" type="String" unsaved-value="null">

<column name="PNUMBER" length="50" sql-type="varchar" not-null="true" unique="true" index="PK_PERSON_1"/>

<generator class="native" />

</id>

<property name="roomcode" type="String" insert="false" update="false" >

<column name="room_code" length="10" sql-type="varchar" not-null="true"/>

</property>

<many-to-one name="dept_info" class="dept_info" column="room_code" not-found="ignore"/>

</class>

</hibernate-mapping>

但这样的话以后字段roomcode不能进行修改操作

2.配置文件

<?xml version="1.0" encoding="utf-8" ?>

<hibernate-mapping xmlns="urn:nhibernate-mapping-2.2">

<class name="PERSON, Sgidi.Model" table="PERSON">

<id name="PNUMBER" type="String" unsaved-value="null">

<column name="PNUMBER" length="50" sql-type="varchar" not-null="true" unique="true" index="PK_PERSON_1"/>

<generator class="native" />

</id>

<property name="roomcode" type="String" insert="false" update="false" >

<column name="room_code" length="10" sql-type="varchar" not-null="true"/>

</property>

<many-to-one name="dept_info" class="dept_info" column="room_code" not-found="ignore"
insert="false" update="false"
/>

</class>

</hibernate-mapping>

参考资料：

reference:

http://codeverity.com/timweaver/nhibernate-invalid-index-for-this-sqlparametercollection/