JPA,Mysql Blob返回的数据太长
byte[]
我的实体中有一些字段,例如:
@Entitypublic class ServicePicture implements Serializable {
private static final long serialVersionUID = 2877629751219730559L;
// seam-gen attributes (you should probably edit these)
@Id
@GeneratedValue
private Long id;
private String description;
@Lob
@Basic(fetch = FetchType.LAZY)
private byte[] picture;
在我的数据库架构上,该字段设置为,BLOB
所以应该没问题。无论如何:每当我尝试插入图片或pdf时-都不比1mb
,我只会收到此信息
16:52:27,327 WARN [JDBCExceptionReporter] SQL Error: 0, SQLState: 2200116:52:27,327 ERROR [JDBCExceptionReporter] Data truncation: Data too long for column 'picture' at row 1
16:52:27,328 ERROR [STDERR] javax.persistence.PersistenceException: org.hibernate.exception.DataException: could not insert: [de.ac.dmg.productfinder.entity.ServicePicture]
16:52:27,328 ERROR [STDERR] at org.hibernate.ejb.AbstractEntityManagerImpl.throwPersistenceException(AbstractEntityManagerImpl.java:629)
16:52:27,328 ERROR [STDERR] at org.hibernate.ejb.AbstractEntityManagerImpl.persist(AbstractEntityManagerImpl.java:218)
16:52:27,328 ERROR [STDERR] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
16:52:27,328 ERROR [STDERR] at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
16:52:27,328 ERROR [STDERR] at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
16:52:27,328 ERROR [STDERR] at java.lang.reflect.Method.invoke(Unknown Source)
16:52:27,328 ERROR [STDERR] at org.jboss.seam.persistence.EntityManagerInvocationHandler.invoke(EntityManagerInvocationHandler.java:46)
16:52:27,328 ERROR [STDERR] at $Proxy142.persist(Unknown Source)
我已经检查了我的MySQL cnf,并将max_allowed
参数设置为16M
-我缺少什么吗?
回答:
这完全取决于用于picture
列的列类型。根据您的需要,使用:
TINYBLOB
:最大长度为255个字节BLOB
:最大长度为65,535字节MEDIUMBLOB
:最大长度16,777,215字节LONGBLOB
:最大长度为4,294,967,295字节
请注意,如果您是通过JPA批注生成表的,则可以通过指定的length
属性来“控制” MySQL将使用的类型Column
,例如:
@Lob @Basic(fetch = FetchType.LAZY)@Column(length=100000)
private byte[] picture;
根据length
,您将获得:
0 < length <= 255 --> `TINYBLOB` 255 < length <= 65535 --> `BLOB`
65535 < length <= 16777215 --> `MEDIUMBLOB`
16777215 < length <= 2³¹-1 --> `LONGBLOB`
以上是 JPA,Mysql Blob返回的数据太长 的全部内容, 来源链接: utcz.com/qa/400509.html