我很难构造一个条件查询来从id=2的角色实体获取“权限”属性。permission属性是set类型,因此我正在创建一个join并从中进行选择,但查询失败,语法异常报告无效:“where子句中的未知列'2l'”
生成错误的条件查询是通过以下方式生成的:
EntityManager entityManager = getEntityManager();
CriteriaBuilder criteriaBuilder = entityManager.getCriteriaBuilder();
CriteriaQuery<Object> criteriaQuery = criteriaBuilder.createQuery();
Class<?> queryScopeClass = temp.pack.commons.user.Role.class;
Root<?> from = criteriaQuery.from(queryScopeClass);
Path<?> idAttrPath = from.get("id");
// also tried criteriaBuilder.equal(attributePath, new Long(2))
Predicate predicate = criteriaBuilder.equal(attributePath, criteriaBuilder.literal(new Long(2)))
criteriaQuery.where(predicate);
Path<?> attributePath = from.get("permissions");
PluralAttributePath<?> pluralAttrPath = (PluralAttributePath<?>)attributePath;
PluralAttribute<?, ?, ?> pluralAttr = pluralAttrPath.getAttribute();
Join<?, ?> join = from.join((SetAttribute<Object,?>)pluralAttr);
TypedQuery<Object> typedQuery = entityManager.createQuery(criteriaQuery.select(join));
return (List<P>)typedQuery.getResultList();
当我执行该行以实际返回结果时,会引发以下异常:
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)
at org.hibernate.ejb.QueryImpl.getResultList(QueryImpl.java:250)
at org.hibernate.ejb.criteria.CriteriaQueryCompiler$3.getResultList(CriteriaQueryCompiler.java:260)
at temp.pack.dao.impl.DefaultDAOService.getProperties(DefaultDAOService.java:628)
...
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.hql.classic.QueryTranslatorImpl.list(QueryTranslatorImpl.java:936)
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)
... 20 more
Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Unknown column '2L' in 'where clause'
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:409)
at com.mysql.jdbc.Util.getInstance(Util.java:384)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1054)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3562)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3494)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1960)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2114)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2696)
at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2105)
at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:2264)
at com.jolbox.bonecp.PreparedStatementHandle.executeQuery(PreparedStatementHandle.java:179)
at org.hibernate.jdbc.AbstractBatcher.getResultSet(AbstractBatcher.java:208)
at org.hibernate.loader.Loader.getResultSet(Loader.java:1869)
at org.hibernate.loader.Loader.doQuery(Loader.java:718)
at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:270)
at org.hibernate.loader.Loader.doList(Loader.java:2449)
... 27 more
角色和权限类已经用JPA和一些Hibernate注释进行了映射,如下所示:
public abstract class Role implements Serializable {
/**
* The id of this role. Internal use only.
*
* @since 1.0
*/
@Id @GeneratedValue
protected long id;
/**
* Set of permissions granted to this role.
*
* @since 1.0
*/
@OneToMany(cascade = { CascadeType.PERSIST, CascadeType.MERGE }, mappedBy="sourceRole")
protected Set<Permission> permissions = new HashSet<Permission>();
...
}
public class Permission implements Serializable {
private static final long serialVersionUID = 1L;
/**
* The id of this permission. Used internally for persistence.
*
* @since 1.0
*/
@Id @GeneratedValue
@Column(name = "PERMISSION_ID")
protected long id;
/**
* The group to which the owner of this permission is being granted permission to.
*
* @since 1.0
*/
@ManyToOne(cascade = { CascadeType.PERSIST, CascadeType.MERGE })
@JoinColumn(name = "TARGET_ROLE_ID")
@ForeignKey(name = "FK_TARGET_GROUP_PERMISSION_ID",
inverseName = "FK_PERMISSION_ID_TARGET_GROUP")
protected Group targetGroup;
/**
* The role that has been granted this permission.
*
* @since 1.0
*/
@ManyToOne(cascade = { CascadeType.PERSIST, CascadeType.MERGE })
@JoinColumn(name = "SOURCE_ROLE_ID")
@ForeignKey(name = "FK_SOURCE_GROUP", inverseName = "FK_GROUP_PERMISSIONS")
private Role sourceRole;
...
}
这个条件查询有什么问题?
我期望对typedquery.getResultList()的调用只返回一个元素的集合列表:id=2的角色的权限对象集合。这是试图从id=2的对象角色中选择(并初始化)仅“权限”集合。
我不熟悉标准查询,很难找到问题所在。
跟进:
下面是Hibernate试图执行的查询:
select permission1_.PERMISSION_ID as PERMISSION1_12_,
permission1_.IS_REQUIRED as IS2_12_,
permission1_.SOURCE_ROLE_ID as SOURCE3_12_,
permission1_.TARGET_ROLE_ID as TARGET4_12_
from (
select ROLE_ID,
NAME,
DESCRIPTION,
IS_ACTION,
LABEL,
null as FIRST_NAME,
null as LAST_NAME,
null as PASSWORD_HASH,
1 as clazz_ from GROUPS
union
select ROLE_ID,
NAME,
null as DESCRIPTION,
null as IS_ACTION,
null as LABEL,
FIRST_NAME,
LAST_NAME,
PASSWORD_HASH,
2 as clazz_ from USERS
)
role0_ inner join PERMISSIONS permission1_ on role0_.ROLE_ID=permission1_.SOURCE_ROLE_ID
where (role0_.ROLE_ID=2L )
显然,2L的问题在于,从MySQL的角度来看,2L实际上是一个字符串或列,因为它上面有一个L,并且没有被引用。
这是冬眠中的虫子吗?在我看来是这样的。我不应该出现在生成的SQL查询中…
有人知道这是怎么回事吗?在我看来,这将是一个主要的错误,不能忽视其他人,所以我假设有一个很好的变化,我正在做一些错误的事情。
谢谢您!!
爱德华多
