Hibernate使用和删除HQL [英] Hibernate HQL delete with and

问题描述

Hibernate不会删除我的行：

  public boolean deleteVote（Login user，int pid）{
 
 Session session = getSession（）; 
 
尝试{
 String hql =从投票中删除，其中uid =：uid和pid =：pid; 
 Query query = session.createQuery（hql）; 
 System.out.println（user.getUid（）+and pid：+ pid）; 
 query.setString（uid，user.getUid（））; 
 query.setInteger（pid，pid）; 
 System.out.println（query.executeUpdate（））; 
} catch（例外e）{
  

Outprint：

  uid：123和pid：1 
 Hibernate：从uid =？和pid =？ 
 1 
  

当我直接在SQL中尝试时，SQL语法正在工作。直接SQL语法：

 从投票中删除where uid ='123'AND pid = 1 
  
 
 
 
映射： 
 
 
 < class name =package.model.Votetable =votes> 
< id name =vidcolumn =vid> 
< generator class =increment/> 
< / id> 
< property name =pidcolumn =pid/> 
< property name =uidcolumn =uid/> 
< property name =tidcolumn =tid/> 
< property name =votescolumn =votes/> 
< / class> 
  
表：
 < code $ CREATE TABLE IF NOT EXISTS`votes`（
`vid` int（11）NOT NULL 
`pid` int（11）NOT NULL，
`uid` varchar 20）NOT NULL，
`tid` int（11）NOT NULL，
`votes` int（11）NOT NULL DEFAULT'1'，
 PRIMARY KEY（`vid`），
 KEY'pcid'（`pid`，`uid`），
 KEY`uid`（`uid`），
 KEY`tid`（`tid`）
）发动机= InnoDB DEFAULT CHARSET = utf8 AUTO_INCREMENT = 10; 
 
 ALTER TABLE`votes` 
 ADD CONSTRAINT`votes_ibfk_3` FOREIGN KEY（`pid`）REFERENCES`poll`（`pid`）ON DELETE CASCADE ON UPDATE CASCADE，
 ADD CONSTRAINT`votes_ibfk_4` FOREIGN KEY（`uid`）REFERENCES`user`（`uid`）ON DELETE CASCADE ON UPDATE CASCADE，
 ADD CONSTRAINT`votes_ibfk_5` FOREIGN KEY（`tid`）REFERENCES`teams`（`tid `）ON DELETE CASCADE ON UPDATE CASCADE; 
 
 INSERT INTO`votes`（`vid`，`pid`，`uid`，`tid`，`votes`）VALUES 
（20,1，'123'，1， 1）; 
  
我觉得这很容易，因为目前为止我的一切看起来都不错。 
 
 
 
任何帮助表示赞赏。
解决方案
您需要开始并提交一个事务。 
 
 
  Transaction transaction = session.beginTransaction（ ）; 
尝试{
 //您的代码
字符串hql =从投票中删除，其中uid =：uid和pid =：pid; 
 Query query = session.createQuery（hql）; 
 System.out.println（user.getUid（）+and pid：+ pid）; 
 query.setString（uid，user.getUid（））; 
 query.setInteger（pid，pid）; 
 System.out.println（query.executeUpdate（））; 
 //您的代码结束
 
 transaction.commit（）; 
} catch（Throwable t）{
 transaction.rollback（）; 
抛出t; 
} 
  
您也可能需要在更改前关闭会话在数据库中可见。
 
Hibernate doesn't delete my row:
public boolean deleteVote(Login user, int pid){

      Session session = getSession();

      try{
          String hql = "delete from Vote where uid= :uid AND pid= :pid";
          Query query = session.createQuery(hql);
          System.out.println(user.getUid() + " and pid: " + pid);
          query.setString("uid", user.getUid());
          query.setInteger("pid", pid);
          System.out.println(query.executeUpdate());
      }catch(Exception e){
Outprint:
uid: 123 and pid: 1
Hibernate: delete from votes where uid=? and pid=?
1
The SQL Syntax is working when I'm trying directly in SQL. Direct SQL Syntax:
 delete from votes where uid= '123' AND pid= 1
Mapping:
<class name="package.model.Vote" table="votes">
   <id name="vid" column="vid" >
   <generator class="increment"/>
</id>
<property name="pid" column="pid" />
<property name="uid" column="uid" />
<property name="tid" column="tid" />
<property name="votes" column="votes" />
 </class>
Table:
CREATE TABLE IF NOT EXISTS `votes` (
  `vid` int(11) NOT NULL 
  `pid` int(11) NOT NULL,
  `uid` varchar(20) NOT NULL,
  `tid` int(11) NOT NULL,
  `votes` int(11) NOT NULL DEFAULT '1',
  PRIMARY KEY (`vid`),
  KEY `pcid` (`pid`,`uid`),
  KEY `uid` (`uid`),
  KEY `tid` (`tid`)
) ENGINE=InnoDB  DEFAULT CHARSET=utf8 AUTO_INCREMENT=10 ;

ALTER TABLE `votes`
ADD CONSTRAINT `votes_ibfk_3` FOREIGN KEY (`pid`) REFERENCES `poll` (`pid`) ON DELETE CASCADE ON UPDATE CASCADE,
ADD CONSTRAINT `votes_ibfk_4` FOREIGN KEY (`uid`) REFERENCES `user` (`uid`) ON DELETE CASCADE ON     UPDATE CASCADE,
ADD CONSTRAINT `votes_ibfk_5` FOREIGN KEY (`tid`) REFERENCES `teams` (`tid`) ON DELETE CASCADE ON UPDATE CASCADE;

INSERT INTO `votes` (`vid`, `pid`, `uid`, `tid`, `votes`) VALUES
(20, 1, '123', 1, 1);
I guess it's something pretty easy because everything looks okay for me so far. I got no error or anything else, just that no delete is happening.

Any help is appreciated.
解决方案
You need to begin and commit a transaction.
Transaction transaction = session.beginTransaction();
try {
  // your code
  String hql = "delete from Vote where uid= :uid AND pid= :pid";
  Query query = session.createQuery(hql);
  System.out.println(user.getUid() + " and pid: " + pid);
  query.setString("uid", user.getUid());
  query.setInteger("pid", pid);
  System.out.println(query.executeUpdate());
  // your code end

  transaction.commit();
} catch (Throwable t) {
  transaction.rollback();
  throw t;
}
It is also possible that you need to close the session before the changes will be visible in the database.

                        
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