无法在Hibernate条件中提取结果集

Question

我得到异常后，我适当的结果criteria.unique结果（）对象报价。目的查询-从数据库Oracle的表“报价”中获得随机结果

org.hibernate.exception.SQLGrammarExc0019：无法提取org.hibernate.exception.internal.SQLExceptionTypeDelegate.convert（SQLExceptionTypeDelegate.java:80）在org.hibernate.exception.internal.标准SQLExceptionConverter.convert（标准SQLExceptionConverter.java:49）在org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert（SqlExceptionHelper.java:126）在org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert（SqlExceptionHelper.java:112）在org.hibernate.engine.jdbc.internal.ResultSetResnImpl.extract（ResultSetResnImpl.java:91）在org.hibernate.loader.Loader.getResultSet（Loader.java:2065）atorg.hibernate.loader.Loader.在org. hibernate. loader.Loader. doQuery（Loader. java： 909）at org. hibernate. loader。在org. hibernate. loader上的Loader. doQueryAnd初始化eNonLazyCollection（Loader. java： 354）。Loader. doList（Loader. java： 2553）在org. hibernate. loader。Loader. doList（Loader. java： 2539）在org. hibernate. loader。Loader. listIgnoreQueryCache（Loader. java： 2369）at org. hibernate. loader。Loader. list（Loader. java： 2364）at org. hibernate. loader.准则。CriteriaLoader. list（CriteriaLoader. java： 126）在org. hibernate. interal。SessionImp. list（SessionInp. java： 1682）在org. hibernate. interal。CriteriaInp. list（CriteriaInp. java： 380）在org. hibernate. interal。CriteriaImp. uniqueResult（CriteriaInp. java： 402）在ua. com. goit. gojava7. kikstarter. dao.数据库。QuoteDaoDbInp. getRlandQuote（QuoteDaoDbInp. java： 42）at sun.反射。nativemethod odAccessorImp. invke0（本机方法）在sun.反射。nativeMEDAccessorInp. invoke（NativeMEDAccessorInp. java： 57）在sun. reff。在java. lang.反射中调用（委托方法访问或执行. java： 43）。在org. springframework. aop. support上调用（method. java： 601）。在org. springframework. aop. framework.java： 190）在org. springframework. aop. framework.java： 157），网址为org. springframework.事务性.拦截器。TransactionInterceptor1美元。在org. springframework.事务性.拦截器上的TransactionAshooSupport. invkeBackinTransaction（TransactionAshooSupport. java： 281）。调用（TransactionInterceptor. java： 96）在org. springframework. aop. framework。java： 179）在org. springframework. aop. framework。jdkDynamicAopProxy. invoke（JdkDynamicAopProxy. java： 207）在com. sun. proxy。$Proxy48. get随机报价（未知来源）在ua. com. goit. gojava7. kikstarter. Controler. servlet。在javax. servlet. http.服务（HttpServlet. java： 621）在javax. servlet. http.服务（HttpServlet. java： 728）在org. apache. catalina. core。在org. apache. catalina. core上的Application ationFilterChain. interalDoFilter（Application ationFilterChain. java： 305）。在org. apache. catalina. core.在org. apache. catalina. core上调用（标准WrapperValve. java： 222）。在org. apache. catalina.身份验证器上调用（Standard ContextValve. java： 123）。在org. apache. catalina. core上调用（AuthentiatorBase. java： 502）。在org. apache. catalina. valves. invoke（Standard HostValve. java： 171）。在org. apache. catalina. valves上调用（ErrorReportValve. java： 99）。AccessLogValve. invoke（AccessLogValve. java： 953）在org. apache. catalina. core。在org. apache. catalina.连接器上调用标准工程师。coyoteAdapter. service（CoyoteAdapter. java： 408）在org. apache. coyot. http 11.进程（AbstractHttp11Processor. java： 1023）在org. apache. coyote。在org. apache. tomcat. util. net上的AbstractProtocol$AbstractConnectionHandler.流程（AbstractAction. java： 589）。JIoEndpoint$SocketProcessor. run（JIoEndpoint. java： 312）at java. util. con当前。ThreadPoolExecutor. runWorker（ThreadPoolExecutor. java： 1145）在java. util. con当前。在java. lang上运行（ThreadPoolExecator. java： 615）。线程.运行（线程. java： 722）

类QuoteDaoDbImpl

@Repository
public class QuoteDaoDbImpl implements QuoteDao {

    private static final String SELECT_RANDOM_QUOTE = "SELECT * FROM (SELECT * FROM quotes ORDER BY DBMS_RANDOM.VALUE) WHERE rownum = 1";

    @Autowired
    private SessionFactory sessionFactory;

    @Transactional
    @Override
    public Quote getRandomQuote() {
        Session session = sessionFactory.getCurrentSession();

        Criteria criteria = session.createCriteria(Quote.class);
        criteria.add(Restrictions.sqlRestriction(SELECT_RANDOM_QUOTE));
        criteria.setMaxResults(1);

        Quote quote = (Quote) criteria.uniqueResult();
        session.close();

        return quote;
    }
}

类别选择类别

@WebServlet("/categories")
public class SelectoinCategories extends HttpServlet {

   /**
    * 
    */
    private static final long serialVersionUID = 1L;

    @Autowired
    private QuoteDao quoteDao;

    @Autowired
    private CategoryDao categoryDao;

    public void init() throws ServletException {

        SpringBeanAutowiringSupport.processInjectionBasedOnServletContext(this, getServletContext());

    }

    protected void doGet(HttpServletRequest request, HttpServletResponse response)
        throws ServletException, IOException {

        Quote quote = quoteDao.getRandomQuote();
        List<Category> categories = categoryDao.getAll();

        request.setAttribute("content", quote.getContent());
        request.setAttribute("author", quote.getAuthor());
        request.setAttribute("categories", categories);
        request.getRequestDispatcher("WEB-INF/jsp/categories.jsp").forward(request, response);

    }
}

类报价

@Entity
@Table(name = "qoutes")
public class Quote {

    @Id
    @SequenceGenerator(name = "SEQ_GEN", sequenceName = "seq_id", allocationSize = 10)
    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "SEQ_GEN")
    private int id;

    @Column(name = "content")
    private String content;

    @Column(name = "author")
    private String author;

    public Quote() {
    }

    public Quote(String content, String author) {
        this.content = content;
        this.author = author;
    }

    public int getId() {
        return id;
    }

    public String getContent() {
        return content;
    }

    public String getAuthor() {
        return author;
    }

    public void setId(int id) {
        this.id = id;
    }

    public void setContent(String quoteContent) {
        this.content = quoteContent;
    }

    public void setAuthor(String quoteAuthor) {
        this.author = quoteAuthor;
    }

    public String toString() {
        return "ID: " + id + "; Content: " + content + "; Author: " + author;
    }

}

表引号

CREATE TABLE quotes
(
id INTEGER NOT NULL,
content VARCHAR2(500) NOT NULL,
author VARCHAR2(100) NOT NULL
);

Answer 1

修改尝试

 private static final String SELECT_RANDOM_QUOTE = 
    "SELECT id, content, author FROM 
    (SELECT * FROM quotes ORDER BY DBMS_RANDOM.VALUE) as quotes  WHERE rownum = 1";