[出错：]做好双向一对多关连后的查询问题

父表
<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 2.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd" >

<hibernate-mapping>
<!--
Created by the Middlegen Hibernate plugin 2.1

http://boss.bekk.no/boss/middlegen/
http://www.hibernate.org/
-->

<class
name="com.mycompany.myapp.hibernate.Father"
table="father"
>
<meta attribute="class-description" inherit="false">
@hibernate.class
table="father"
</meta>

<id
name="fatherId"
type="java.lang.String"
column="fatherId"
>
<meta attribute="field-description">
@hibernate.id
generator-class="uuid.hex"
type="java.lang.String"
column="fatherId"


</meta>
<generator class="uuid.hex" />
</id>

<property
name="name"
type="java.lang.String"
column="name"
not-null="true"
length="100"
>
<meta attribute="field-description">
@hibernate.property
column="name"
length="100"
not-null="true"
</meta>
</property>
。。。。。。。。略

<!-- Associations -->

<!-- bi-directional one-to-many association to Son -->
<set
name="son"
lazy="false"
inverse="true"
cascade="none"
>
<meta attribute="field-description">
@hibernate.set
lazy="false"
inverse="true"
cascade="none"

@hibernate.collection-key
column="fatherId"

@hibernate.collection-one-to-many
class="com.mycompany.myapp.hibernate.Son"
</meta>
<key>
<column name="fatherId" />
</key>
<one-to-many
class="com.mycompany.myapp.hibernate.Son"
/>
</set>

</class>
</hibernate-mapping>

子表：
<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 2.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd" >

<hibernate-mapping>
<!--
Created by the Middlegen Hibernate plugin 2.1

http://boss.bekk.no/boss/middlegen/
http://www.hibernate.org/
-->

<class
name="com.mycompany.myapp.hibernate.Son"
table="son"
>
<meta attribute="class-description" inherit="false">
@hibernate.class
table="son"
</meta>

<id
name="sonId"
type="java.lang.String"
column="sonId"
>
<meta attribute="field-description">
@hibernate.id
generator-class="uuid.hex"
type="java.lang.String"
column="sonId"


</meta>
<generator class="uuid.hex" />
</id>

<property
name="sonName"
type="java.lang.String"
column="sonName"
not-null="true"
length="100"
>
<meta attribute="field-description">
@hibernate.property
column="sonName"
length="100"
not-null="true"
</meta>
</property>
。。。。。。。。略
<!-- Associations -->

<!-- bi-directional many-to-one association to Father -->
<many-to-one
name="father"
class="com.mycompany.myapp.hibernate.Father"
not-null="true"
cascade="none"
outer-join="auto"
>
<meta attribute="field-description">
@hibernate.many-to-one
not-null="true"
@hibernate.column name="fatherId"
</meta>
<column name="fatherId" />
</many-to-one>

</class>
</hibernate-mapping>
以上都是hib自带工具生成的，po中也是生成的，父表po中有子表对应的set集合，但是在执行查询：
select count(*) FROM com.mycompany.myapp.hibernate.Son Son , com.mycompany.myapp.hibernate.Father Father where Father.fatherId=Son.fatherId
时报错：javax.servlet.ServletException: net.sf.hibernate.QueryException: could not resolve property: fatherId of: com.mycompany.myapp.hibernate.Son [select count(*) FROM com.mycompany.myapp.hibernate.Son Son , com.mycompany.myapp.hibernate.Father Father where Father.fatherId=Son.fatherId]
org.apache.struts.action.RequestProcessor.processException(RequestProcessor.java:516)
org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:423)
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:226)
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1164)
org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:397)
javax.servlet.http.HttpServlet.service(HttpServlet.java:743)
javax.servlet.http.HttpServlet.service(HttpServlet.java:856)


root cause

java.lang.RuntimeException: net.sf.hibernate.QueryException: could not resolve property: fatherId of: com.mycompany.myapp.hibernate.Son [select count(*) FROM com.mycompany.myapp.hibernate.Son Son , com.mycompany.myapp.hibernate.Father Father where Father.fatherId=Son.fatherId]
com.util.tools.PageTools.getEntityCount(PageTools.java:106)
com.onetomany.actionBean.fatherAction.execute(fatherAction.java:109)
org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:421)
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:226)
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1164)
org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:397)
javax.servlet.http.HttpServlet.service(HttpServlet.java:743)
javax.servlet.http.HttpServlet.service(HttpServlet.java:856)

我在做极联插入时没问题，证明我的配置没问题，但查询为何执行不了。
另外，使用
select count(*) FROM com.mycompany.myapp.hibernate.Son Son inner join com.mycompany.myapp.hibernate.Father Father on Father.fatherId=Son.fatherId
也不行。请兄弟们解答，偶刚用不久。。。谢谢

你的子表映射文件里应该没有fatherId这个Column吧.

但在你的Servelt里是否引用了SonClass.getFatherId()之类的？这样是不对的。

可否把你的Servlet,SonClass,以及FatherClass铁出来

引用，只能是SonClass.getFather().getFatherId()

子表隐射没有column，否则会与 <many-to-one的地方产生冲突；
下面是son的java文件：
package com.mycompany.myapp.hibernate;
import java.util.Set;
import java.util.HashSet;
import java.io.Serializable;
import java.util.Date;

public class Son
implements Serializable {
private SonPk sonPk;

/**
* This attribute maps to the column sonId in the son table.
*/
private String sonId;

/**
* This attribute maps to the column fatherId in the son table.
*/
private String fatherId;

/**
* This attribute maps to the column sonName in the son table.
*/
private String sonName;

/**
* This attribute maps to the column sonSex in the son table.
*/
private String sonSex;

/**
* This attribute maps to the column sonWeight in the son table.
*/
private float sonWeight;

/**
* This attribute represents whether the primitive attribute sonWeight is null.
*/
private boolean sonWeightNull = true;

/**
* This attribute maps to the column sonAddress in the son table.
*/
private String sonAddress;

/**
* This attribute maps to the column sonBirthday in the son table.
*/
private Date sonBirthday;

/**
* This attribute maps to the column sonOld in the son table.
*/
private int sonOld;

/**
* This attribute represents whether the primitive attribute sonOld is null.
*/
private boolean sonOldNull = true;

/**
* This attribute maps to the column sonMemo in the son table.
*/
private String sonMemo;

private Father Father;

/**
* Method 'Son'
*
*/
public Son() {
}

public void setFather(Father Father) {
this.Father = Father;
}

public Father getFather() {
return Father;
}

/**
* Sets the value of sonPk
*/
public void setSonPk(SonPk sonPk) {
this.sonPk = sonPk;
}

/**
* Gets the value of sonPk
*/
public SonPk getSonPk() {
return sonPk;
}

/**
* Method 'getSonId'
*
* @return java.lang.String
*/
public java.lang.String getSonId() {
return sonId;
}

/**
* Method 'setSonId'
*
* @param sonId
*/
public void setSonId(java.lang.String sonId) {
this.sonId = sonId;
}

/**
* Method 'getFatherId'
*
* @return java.lang.String
*/
public java.lang.String getFatherId() {
return fatherId;
}
/**
* Method 'setFatherId'
*
* @param fatherId
*/
public void setFatherId(java.lang.String fatherId) {
this.fatherId = fatherId;
}

/**
* Method 'getSonName'
*
* @return java.lang.String
*/
public java.lang.String getSonName() {
return sonName;
}

/**
* Method 'setSonName'
*
* @param sonName
*/
public void setSonName(java.lang.String sonName) {
this.sonName = sonName;
}

/**
* Method 'getSonSex'
*
* @return java.lang.String
*/
public java.lang.String getSonSex() {
return sonSex;
}

/**
* Method 'setSonSex'
*
* @param sonSex
*/
public void setSonSex(java.lang.String sonSex) {
this.sonSex = sonSex;
}

/**
* Method 'getSonWeight'
*
* @return float
*/
public float getSonWeight() {
return sonWeight;
}

/**
* Method 'setSonWeight'
*
* @param sonWeight
*/
public void setSonWeight(float sonWeight) {
this.sonWeight = sonWeight;
setSonWeightNull(false);
}

/**
* Sets the value of sonWeightNull
*/
public void setSonWeightNull(boolean sonWeightNull) {
this.sonWeightNull = sonWeightNull;
}

/**
* Gets the value of sonWeightNull
*/
public boolean isSonWeightNull() {
return sonWeightNull;
}

/**
* Method 'getSonAddress'
*
* @return java.lang.String
*/
public java.lang.String getSonAddress() {
return sonAddress;
}

/**
* Method 'setSonAddress'
*
* @param sonAddress
*/
public void setSonAddress(java.lang.String sonAddress) {
this.sonAddress = sonAddress;
}

/**
* Method 'getSonBirthday'
*
* @return java.util.Date
*/
public java.util.Date getSonBirthday() {
return sonBirthday;
}

/**
* Method 'setSonBirthday'
*
* @param sonBirthday
*/
public void setSonBirthday(java.util.Date sonBirthday) {
this.sonBirthday = sonBirthday;
}

/**
* Method 'getSonOld'
*
* @return int
*/
public int getSonOld() {
return sonOld;
}

/**
* Method 'setSonOld'
*
* @param sonOld
*/
public void setSonOld(int sonOld) {
this.sonOld = sonOld;
setSonOldNull(false);
}

/**
* Sets the value of sonOldNull
*/
public void setSonOldNull(boolean sonOldNull) {
this.sonOldNull = sonOldNull;
}

/**
* Gets the value of sonOldNull
*/
public boolean isSonOldNull() {
return sonOldNull;
}

/**
* Method 'getSonMemo'
*
* @return java.lang.String
*/
public java.lang.String getSonMemo() {
return sonMemo;
}

/**
* Method 'setSonMemo'
*
* @param sonMemo
*/
public void setSonMemo(java.lang.String sonMemo) {
this.sonMemo = sonMemo;
}

/**
* Method 'equals'
*
* @param _other
* @return boolean
*/
public boolean equals(Object _other) {
if (_other == null) {
return false;
}

if (_other == this) {
return true;
}

if (! (_other instanceof Son)) {
return false;
}

final Son _cast = (Son) _other;
if (sonPk == null ? _cast.sonPk != sonPk : !sonPk.equals(_cast.sonPk)) {
return false;
}

if (sonId == null ? _cast.sonId != sonId : !sonId.equals(_cast.sonId)) {
return false;
}

if (sonName == null ? _cast.sonName != sonName :
!sonName.equals(_cast.sonName)) {
return false;
}

if (sonSex == null ? _cast.sonSex != sonSex : !sonSex.equals(_cast.sonSex)) {
return false;
}

if (sonWeight != _cast.sonWeight) {
return false;
}

if (sonWeightNull != _cast.sonWeightNull) {
return false;
}

if (sonAddress == null ? _cast.sonAddress != sonAddress :
!sonAddress.equals(_cast.sonAddress)) {
return false;
}

if (sonBirthday == null ? _cast.sonBirthday != sonBirthday :
!sonBirthday.equals(_cast.sonBirthday)) {
return false;
}

if (sonOld != _cast.sonOld) {
return false;
}

if (sonOldNull != _cast.sonOldNull) {
return false;
}

if (sonMemo == null ? _cast.sonMemo != sonMemo :
!sonMemo.equals(_cast.sonMemo)) {
return false;
}

return true;
}

/**
* Method 'hashCode'
*
* @return int
*/
public int hashCode() {
int _hashCode = 0;
if (sonPk != null) {
_hashCode = 29 * _hashCode + sonPk.hashCode();
}

if (sonId != null) {
_hashCode = 29 * _hashCode + sonId.hashCode();
}

if (sonName != null) {
_hashCode = 29 * _hashCode + sonName.hashCode();
}

if (sonSex != null) {
_hashCode = 29 * _hashCode + sonSex.hashCode();
}

_hashCode = 29 * _hashCode + Float.floatToIntBits(sonWeight);
_hashCode = 29 * _hashCode + (sonWeightNull ? 1 : 0);
if (sonAddress != null) {
_hashCode = 29 * _hashCode + sonAddress.hashCode();
}

if (sonBirthday != null) {
_hashCode = 29 * _hashCode + sonBirthday.hashCode();
}

_hashCode = 29 * _hashCode + sonOld;
_hashCode = 29 * _hashCode + (sonOldNull ? 1 : 0);
if (sonMemo != null) {
_hashCode = 29 * _hashCode + sonMemo.hashCode();
}

return _hashCode;
}

}
自动生成的；另外，在这个文件里面不论是否定义fatherId是没有区别的，照样报错。

Servelt里是否引用了SonClass.getFatherId()之类的？
答：在servlet中并没有执行到这一步，就那个sql就执行不了，报那个错了；而且执行单表查询是不会报错的

我觉得是blade_rain用法有误。
1, 如果b成员在...hbm.xml 里没有映射声明的话 himbernate是不会知道对象有b这个属性的，所以 hql 里用 'Son.fatherId ' 本身就不对...
2, 如果用了一对多的父子关系(father-son)，对数据库而言,就是在子表(son对映的表)里加一个外键，列名就是father里<set>部分声明的(blade_rain用的是'fatherId'), 估计正好和son的fatherId 属性映射的列名一样。所以原来会有冲突，数据库字段重复了!
3. 其实如果想查询 son , hql 直接用 from com.mycompany.myapp.hibernate.Son 就可以了, father 可以用 son.getFather() 得到。

第一次发贴，不知说的对不对...

还是一对多的关系

双相关联

通过hql:
son.father.id就可以取得father的id

如果是取有孩子的Father总数可以如下:

select count(distinct son.father.id) from Son as son

执行的sql是:

select count(distinct son0_.father_id) as x0_0_ from son son0_