h2数据库to_char别名抛出空指针

Posted 2023-03-28

【中文标题】h2数据库to_char别名抛出空指针

【英文标题】：h2 database to_char alias throwing null pointer

【发布时间】：2014-03-20 20:56:50

【问题描述】：

HQL 在 oracle 数据库中运行良好，但在使用 h2 数据库 1.3 时抛出空指针。 175

Query q = session.createQuery(
    "select new TESTPOJO(c.name, c.phoneNumber, " + 
    "to_char(c.dateofBirth, 'YY') from STUDENT c " + 
    "where c.gender= :gender " + 
    "group by to_char(c.dateofBirth, 'YY') );
q.setString("gender", "Male");
result = q.list();

下面是日志...如何在H2中使用to_char()别名

java.lang.NullPointerException
    at org.hibernate.internal.util.ReflectHelper.getConstructor(ReflectHelper.java:355)
    at org.hibernate.hql.internal.ast.tree.ConstructorNode.resolveConstructor(ConstructorNode.java:179)
    at org.hibernate.hql.internal.ast.tree.ConstructorNode.prepare(ConstructorNode.java:152)
    at org.hibernate.hql.internal.ast.HqlSqlWalker.processConstructor(HqlSqlWalker.java:1019)
    at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.selectExpr(HqlSqlBaseWalker.java:2150)
    at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.selectExprList(HqlSqlBaseWalker.java:2016)
    at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.selectClause(HqlSqlBaseWalker.java:1451)
    at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.query(HqlSqlBaseWalker.java:571)
    at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.selectStatement(HqlSqlBaseWalker.java:299)
    at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.statement(HqlSqlBaseWalker.java:247)
    at org.hibernate.hql.internal.ast.QueryTranslatorImpl.analyze(QueryTranslatorImpl.java:248)
    at org.hibernate.hql.internal.ast.QueryTranslatorImpl.doCompile(QueryTranslatorImpl.java:183)
    at org.hibernate.hql.internal.ast.QueryTranslatorImpl.compile(QueryTranslatorImpl.java:136)
    at org.hibernate.engine.query.spi.HQLQueryPlan.<init>(HQLQueryPlan.java:105)
    at org.hibernate.engine.query.spi.HQLQueryPlan.<init>(HQLQueryPlan.java:80)
    at org.hibernate.engine.query.spi.QueryPlanCache.getHQLQueryPlan(QueryPlanCache.java:168)
    at org.hibernate.internal.AbstractSessionImpl.getHQLQueryPlan(AbstractSessionImpl.java:219)
    at org.hibernate.internal.AbstractSessionImpl.createQuery(AbstractSessionImpl.java:197)
    at org.hibernate.internal.SessionImpl.createQuery(SessionImpl.java:1736)
    at com.ens.stomp.schema.ect4.dao.ClaimsReportingDAO.getFrontEndRejections(ClaimsReportingDAO.java:180)
    at com.ens.stomp.persistence.claim.professional.v5010.h2.ect4.ECT4ReportingDAOTest.testGetFrontEndRejections(ECT4ReportingDAOTest.java:121)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at util.h2.SessionFactoryRule$1.evaluate(SessionFactoryRule.java:54)
    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)

【问题讨论】：

请尝试使用代码格式化工具使您的帖子更具可读性

【参考方案1】：

使用较新的 H2 db 版本 1.3.175。自 2014-01-18 起可使用 TO_CHAR 函数。