hibernate 未明确定义列 小记[通俗易懂]

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 在写关联表的实体类时，用测试代码去运行，出现
16:00:30,817 ERROR JDBCExceptionReporter:72 – ORA-00918: 未明确定义列

16:00:30,833 ERROR PersistSpringImpl:244 – [PersistImpl][find(queryString, offset, length)] hql: from com.esse.projects.cpinfo.entity.MemberList
org.springframework.jdbc.BadSqlGrammarException: Hibernate operation: could not execute query; bad SQL grammar [select memberlist0_.Member_ID as Member1_87_, memberlist0_.MEMBERRECORD_ID as MEMBERRE2_87_, memberlist0_.MEMBER_ID as MEMBER1_87_ from MemberList memberlist0_]; nested exception is java.sql.SQLException: ORA-00918: 未明确定义列

java.sql.SQLException: ORA-00918: 未明确定义列
我的各个相应实体，配置文件如下：
数据库关系图如下：

概念模型

下一：物理模型

1.实体类
public class MemberList extends AbstractEntity implements Serializable {

    /**
     *
     */
    private static final long serialVersionUID = 30680140753579543L;
    private MemberListPK id;
    private MemberRecord memberRecord;
    private Member member;

    public MemberRecord getMemberRecord() {

        return memberRecord;
    }
    public void setMemberRecord(MemberRecord memberRecord) {

        this.memberRecord = memberRecord;
    }
    public Member getMember() {

        return member;
    }
    public void setMember(Member member) {

        this.member = member;
    }
    public MemberListPK getId() {

        return id;
    }
    public void setId(MemberListPK id) {

        this.id = id;
    }

}

2.MemberListPK联合主键实体类
public class MemberListPK implements Serializable {

    /**
     *
     */
    private static final long serialVersionUID = 8074810556884497882L;
    private long memberId;
    private long memberRecordId;

    public long getMemberId() {

        return memberId;
    }

    public void setMemberId(long memberId) {

        this.memberId = memberId;
    }

    public long getMemberRecordId() {

        return memberRecordId;
    }

    public void setMemberRecordId(long memberRecordId) {

        this.memberRecordId = memberRecordId;
    }

    public boolean equals(Object other) {

        if (this == other) {

            return true;
        }
        if (!(other instanceof MemberListPK)) {

            return false;
        }
        MemberListPK castOther = (MemberListPK)other;
        return new EqualsBuilder()
            .append(this.getMemberId(), castOther.getMemberId())
            .append(this.getMemberRecordId(), castOther.getMemberRecordId())
            .isEquals();
    }

    public int hashCode() {

        return new HashCodeBuilder()
            .append(this.getMemberId())
            .append(this.getMemberRecordId())
            .toHashCode();
    }

}
3.hbm.xml文件
<?xml version=”1.0″?>
<!DOCTYPE hibernate-mapping PUBLIC
    “-//Hibernate/Hibernate Mapping DTD 3.0//EN”
    “http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd”>

<hibernate-mapping>
    <class name=”com.esse.projects.cpinfo.entity.MemberList”
        table=”MemberList”>

        <composite-id name=”id”
            class=”com.esse.projects.cpinfo.entity.MemberListPK”>
            <key-property name=”memberId” type=”long”
                column=”Member_ID” />
            <key-property name=”memberRecordId” type=”long”
                column=”MEMBERRECORD_ID” />
        </composite-id>

        <!– Associations –>
        <many-to-one name=”member” class=”com.esse.projects.cpinfo.entity.Member” insert=”false” update=”false”>
            <column name=”MEMBER_ID” />
        </many-to-one>
        <many-to-one name=”memberRecord” class=”com.esse.projects.cpinfo.entity.MemberRecord” insert=”false” update=”false”>
            <column name=”MEMBERRECORD_ID” />
        </many-to-one>
    </class>
</hibernate-mapping>
4.在运行测试类时，会出现 未明确定义列，查看hibernat生成的sql语句，发现sql执行的是：
select memberlist0_.Member_ID       as Member1_87_,
       memberlist0_.MEMBERRECORD_ID as MEMBERRE2_87_,
       memberlist0_.MEMBER_ID       as MEMBER1_87_
  from MemberList memberlist0_
为什么对于MEMBER_ID字段查询两次呢，想不明白，仔细查看MemberList.hbm.xml文件原来，
<key-property name=”memberId” type=”long”
                column=”Member_ID” />
<many-to-one name=”member” class=”com.esse.projects.cpinfo.entity.Member” insert=”false” update=”false”>
            <column name=”MEMBER_ID” />
对于同一个MEMBER_ID字段，两个大小写不一致。导致sql生成的也不一样。
解决方法：把MEMBER_ID字段统一，要不全大写，要不全小写。