ORA-02291: 违反完整约束条件 (UNISPOWER.FK932556A9840256A3) - 未找到父项关键字
错误
Caused by: org.hibernate.exception.ConstraintViolationException: Could not execute JDBC batch update
ORA-02291: 违反完整约束条件 (UNISPOWER.FK932556A9840256A3) - 未找到父项关键字
可能原因
表A中有个字段是外键,关联了表B中的某字段,再往表A插入数据时,会出现这种情况。
可能原因:
1.在往A表插入时,外键关联的字段在B表中必须有数据,如果B表中没有数据则又这种情况。
2.产生了外键环,就是B表中被外键关联的字段又关联了C表中的字段,而C中相应字段却没有数据,则产生这种情况。
3.如果不是上两种情况,那么就是一个非常容易疏忽的问题:A中的外键字段和B中的被外键关联字段数据类型和长度不一致。特别是数据长度,必须要一致。
主表和从表中的数据类型的长度不一样。
在Hibernate+spring下运行正常,到springRMI下有问题
Could not execute JDBC batch update; nested exception is
ORA-02291: 违反完整约束条件 (UNISPOWER.FK59EE1CFB72ACDA11) - 未找到父项关键字
我的原因:
由于映射实体类的配置对id属性的设置一直是自动生成的。程序中有对id赋值的语句,导致插入表格时候的id值,和赋给下面关联表格中的参考id值不一直。
就出现了上面的错误,因为substation表格中的id值是自动生成的,当然和程序中我赋值给的id值不同,后面的bay等又都是根据我程序中给的id值做参考外键。
这个问题真的是在网上找不到啊……
修改方法是将**.hbm.xml文件中id设置属性修改
column="SUBSTATION_ID"
type="java.lang.Long"
unsaved-value="-1"
>
原来的generator一直是native这表示根据底层数据库自动选择适当的自动id生成策略
现在的assigned表示让应用程序在调用save()之前为对象分配一个标示符。其实如果不指定generator默认就是这种。真的很白痴的问题啊!!
这个生成器使用一个自然键(natural key,有商业意义的列-译注)作为主键,而不是使用一个代理键( surrogate key,没有商业意义的列-译注)。这是没有指定
【需要注意】当选择 assigned 生成器时,,除非有一个 version 或 timestamp 属性,或者你定义
了 Interceptor.isUnsaved(),否则需要让 Hiberante 使用 unsaved-value="undefined",强制
Hibernatet 查询数据库来确定一个实例是瞬时的(transient) 还是脱管的(detached)。
相关阅读:
SPFILE 错误导致数据库无法启动(ORA-01565)
ORA-01172、ORA-01151错误处理
ORA-00600 [2662]错误解决

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