奇怪的java.sql.SQLException:找不到列'fk_Content'

Question

我在MySQL数据库中有两个表:

1-活动:

• pkid:主键.
• fk_Content:内容表上的外键.
• tk_DistributionGroup:类型表distribution_group上的外键.

2-内容:

• pkid:主键.
• tk_contentSubtype:类型表distribution_list上的外键.

我有一个名为CampaignData的java bean(不是hibernate实体)

public class CampaignData {

    private long contentId;
    private long contentSubTypeId;
    private Long distributionGroupId;

}

这是我如何进行查询:

CampaignData campaignData = (CampaignData) session
                .createSQLQuery(
                        "select camp.fk_Content as contentId,camp.tk_DistributionGroup as distributionGroupId,cont.tk_contentSubtype as contentSubTypeId "
                                + "from campaign camp,content cont"
                                + " where camp.pkid=:campaignId and camp.fk_Content=cont.pkid")
                .setLong("campaignId", campaignId)
                .setResultTransformer(
                        Transformers.aliasToBean(CampaignData.class))
                .uniqueResult();

它产生hibernate查询:

select
        camp.fk_Content as contentId,
        camp.tk_DistributionGroup as distributionGroupId,
        cont.tk_contentSubtype as contentSubTypeId 
    from
        campaign camp,
        content cont 
    where
        camp.pkid=? 
        and camp.fk_Content=cont.pkid

当我在数据库中尝试生成的SQL查询时,它工作正常并且数据检索成功,但在运行应用程序时,我得到异常:

Exception in thread "main" org.hibernate.exception.SQLGrammarException: could not execute query
    at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:92)
    at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:66)
    at org.hibernate.loader.Loader.doList(Loader.java:2297)
    at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2172)
    at org.hibernate.loader.Loader.list(Loader.java:2167)
    at org.hibernate.loader.custom.CustomLoader.list(CustomLoader.java:316)
    at org.hibernate.impl.SessionImpl.listCustomQuery(SessionImpl.java:1832)
    at org.hibernate.impl.AbstractSessionImpl.list(AbstractSessionImpl.java:165)
    at org.hibernate.impl.SQLQueryImpl.list(SQLQueryImpl.java:179)
    at org.hibernate.impl.AbstractQueryImpl.uniqueResult(AbstractQueryImpl.java:859)
    at com.xeno.xecamp.desktopManagement.Main.getCampaignSMSs(Main.java:43)
    at com.xeno.xecamp.desktopManagement.Main.main(Main.java:18)
Caused by: java.sql.SQLException: Column 'fk_Content' not found.
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1073)
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:987)
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:982)
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:927)
    at com.mysql.jdbc.ResultSetImpl.findColumn(ResultSetImpl.java:1144)
    at com.mysql.jdbc.ResultSetImpl.getBigDecimal(ResultSetImpl.java:1414)
    at org.hibernate.type.BigIntegerType.get(BigIntegerType.java:57)
    at org.hibernate.type.NullableType.nullSafeGet(NullableType.java:184)
    at org.hibernate.type.NullableType.nullSafeGet(NullableType.java:210)
    at org.hibernate.loader.custom.CustomLoader$ScalarResultColumnProcessor.extract(CustomLoader.java:501)
    at org.hibernate.loader.custom.CustomLoader$ResultRowProcessor.buildResultRow(CustomLoader.java:447)
    at org.hibernate.loader.custom.CustomLoader.getResultColumnOrRow(CustomLoader.java:344)
    at org.hibernate.loader.Loader.getRowFromResultSet(Loader.java:647)
    at org.hibernate.loader.Loader.doQuery(Loader.java:745)
    at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:270)
    at org.hibernate.loader.Loader.doList(Loader.java:2294)
    ... 9 more

请告诉我为什么我会得到例外.

更新:这是第三方应用程序,它在数据库上连接另一个应用程序.

另一个应用价值 hibernate.hbm2ddl.auto=create-drop

Answer 1

为了从数据库中正确地获取您请求的内容,hibernate使用的Entity类应该匹配100%的数据库表.

您有列,fk_Content但私有字段是contentId.只是使用as将无法获得所需的结果.如果你想使用不同的名称(就像你一样),你需要使用正确的列名为hibernate提供@Column(name = "").此外,不建议使用基本数据类型.您的CampaignData类看起来像:

@Entity
@Table(name = "campaign")
public class CampaignData {

    private Long contentId;
    private Long contentSubTypeId;
    private Long distributionGroupId;

    @Id
    @GeneratedValue(strategy=GenerationType.IDENTITY)
    @Column(name = "pkid", unique = true, nullable = false)
    public Long getContentId() {
        return this.contentId;
    }

    public void setContentId(Long contentId){
        this.contentId = contentId;
    }

    @Column(name = "fk_Content")
    public Long getContentSubTypeId() {
        return this.contentSubTypeId;
    }

    public void setContentSubTypeId(Long contentSubTypeId){
        this.contentSubTypeId= contentSubTypeId;
    }

    @Column(name = "tk_DistributionGroup")
    public Long getDistributionGroupId() {
        return this.distributionGroupId;
    }

    public void setDistributionGroupId(Long distributionGroupId){
        this.distributionGroupId= distributionGroupId;
    }
}

这应该做到这一点.另外,尝试学习使用Hibernate的Criteria.这是一种比硬编码SQL语句更好的做法.

Answer 2

为了让它工作,我需要使用addScalar,如下所示:

.createSQLQuery(
                        "select camp.fk_Content as contentId,camp.tk_DistributionGroup as distributionGroupId,cont.tk_contentSubtype as contentSubTypeId "
                                + "from campaign camp,content cont"
                                + " where camp.pkid=:campaignId and camp.fk_Content=cont.pkid")
                .addScalar("contentId")
                .addScalar("distributionGroupId")
                .addScalar("contentSubTypeId")