我想从使用Hibernate 3.5.6的HSQL 2.0数据库加载一个字节数据(用@Lob注释)的实体。这个实体能够被保存而没有任何问题,并且如果它在缓存中(即,不需要被水合)就可以被正确加载。然而,当实体不在缓存中(需要被水合),我收到以下异常:休眠/ hsqldb 2无法水合Blob列
Caused by: org.hsqldb.HsqlException: incompatible data type in conversion: from SQL type BLOB to [B, value: instance of org.hsqldb.types.BlobDataID
at org.hsqldb.error.Error.error(Unknown Source)
... 68 more
以下是完整的堆栈跟踪(减去一些特定领域的痕迹)的详细背景:
javax.persistence.PersistenceException: org.hibernate.exception.SQLGrammarException: could not execute query
at org.hibernate.ejb.AbstractEntityManagerImpl.convert(AbstractEntityManagerImpl.java:1235)
at org.hibernate.ejb.AbstractEntityManagerImpl.convert(AbstractEntityManagerImpl.java:1168)
...
Caused by: 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:2452)
at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2192)
at org.hibernate.loader.Loader.list(Loader.java:2187)
at org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:452)
at org.hibernate.hql.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:363)
at org.hibernate.engine.query.HQLQueryPlan.performList(HQLQueryPlan.java:196)
at org.hibernate.impl.SessionImpl.list(SessionImpl.java:1258)
at org.hibernate.impl.QueryImpl.list(QueryImpl.java:102)
at org.hibernate.ejb.QueryImpl.getResultList(QueryImpl.java:241)
... 45 more
Caused by: java.sql.SQLSyntaxErrorException: incompatible data type in conversion: from SQL type BLOB to [B, value: instance of org.hsqldb.types.BlobDataID
at org.hsqldb.jdbc.Util.sqlException(Unknown Source)
at org.hsqldb.jdbc.Util.throwError(Unknown Source)
at org.hsqldb.jdbc.JDBCResultSet.getColumnInType(Unknown Source)
at org.hsqldb.jdbc.JDBCResultSet.getBytes(Unknown Source)
at org.hsqldb.jdbc.JDBCResultSet.getBytes(Unknown Source)
at org.hibernate.type.AbstractBynaryType.get(AbstractBynaryType.java:103)
at org.hibernate.type.NullableType.nullSafeGet(NullableType.java:186)
at org.hibernate.type.NullableType.nullSafeGet(NullableType.java:175)
at org.hibernate.type.AbstractType.hydrate(AbstractType.java:105)
at org.hibernate.persister.entity.AbstractEntityPersister.hydrate(AbstractEntityPersister.java:2267)
at org.hibernate.loader.Loader.loadFromResultSet(Loader.java:1443)
at org.hibernate.loader.Loader.instanceNotYetLoaded(Loader.java:1371)
at org.hibernate.loader.Loader.getRow(Loader.java:1271)
at org.hibernate.loader.Loader.getRowFromResultSet(Loader.java:619)
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:2449)
... 53 more
Caused by: org.hsqldb.HsqlException: incompatible data type in conversion: from SQL type BLOB to [B, value: instance of org.hsqldb.types.BlobDataID
at org.hsqldb.error.Error.error(Unknown Source)
... 68 more
当我使用Hibernate 3.5.6和HSQL 1.8.0.10时,可能因为使用了不同的方言(Blob列在HSQL 1.8中不受支持)而没有发生此问题。我正在使用的Hibernate版本应该支持HSQL 2,并且我已检查它是否正确检测到HSQL版本并使用正确的方言。当我使用MySQL时,这个问题也不会发生。
有问题的实体已被设置LOB列了,像这样:
@Entity
public class ImageEntity extends IdEntity {
@Lob
@Column(name="IMAGE")
private byte[] imageBytes;
...
这是一个Hibernate/HSQL 2.0的bug?
感谢您报告这一点。现在可以在http://hsqldb.org/support上找到2.0.1的快照jar并修复。 – fredt 2011-02-18 00:30:33