hibernate 执行sql ,select 返回string long

1.执行sql，返回一个结果集，适用查询一个字段并返回一条记录

public Long findSeqTbTest() {      String sql = "select SEQ_TB_TEST.nextval from dual";      SQLQuery query = this.getSession().createSQLQuery(sql);      String str = query.uniqueResult().toString();      return Long.valueOf(str);  }  

//获取表中最小的id  String sql = "select min(a.employeeid) from Emplyees a";  Long id = (Long) session.createQuery(sql).uniqueResult();    //获取数据库时间mysql  String sql = "select now() from dual";  String time =  session.createSQLQuery(sql).uniqueResult().toString();  

2.删除、更新等操作，这里参数是从0开始的

public void deleteTbTest(Long id) {      String hql = "DELETE FROM TbTest WHERE ID = ?";      this.getSession().createQuery(hql).setLong(0, id).executeUpdate();  }  

public void updateTbTest(Date date, boolean flag) {      String sql = "update tb_test set t_name=? where t_status!=1 and t_date" + (flag ? "<?" : "=?");      SQLQuery query = this.getSession().createSQLQuery(sql);      query.setString(0,flag ? "hello": "hi").setDate(1, date).executeUpdate();  }  

3.执行sql，查询单表中多条数据

//尽量避免适用"*"  String sql = "select * from employee e where e.valid=1 and not exists (select employeeid from attendance a where a.employeeid=e.employeeid and a.date = ?)";  SQLQuery query = getSession().createSQLQuery(sql);  query.addEntity(Employee.class).setDate(0, day);  List<Employee> retList = query.list();  

4.查询多表

String hql = "select new map(dept.deptID as deptID,dept.depNo as deptNo,dept.deptName as deptName,emp.empName as empName,emp.empID as empID,emp.empAge as age,emp.empNo as empNo) from Department dept ,Employee emp where dept.depID = emp.depID and emp.empName = ? and emp.sex = ?";  return getHibernateTemplate().find(hql, new Object[] { name, sex }); 

每个字段都保存在map中（key是字段名，value是此字段的值如：[{empID=1,empName=leona,...},...]）

5.查询多表

 

String sql = "select dept.deptID as deptID,dept.depNo as deptNo,dept.deptName as deptName,emp.empName as empName,emp.empID as empID,emp.empAge as age,emp.empNo as empNo,emp.birthday as birthday from Employee emp LEFT JOIN Department dept on dept.depID = emp.depID where empName = ?";          return (List<EmpBean>) this.getSession()              .createSQLQuery(sql)              .addScalar("deptID", Hibernate.STRING)              .addScalar("deptNo", Hibernate.STRING)              .addScalar("deptName", Hibernate.STRING)              .addScalar("empName", Hibernate.STRING)              .addScalar("empID", Hibernate.STRING)              .addScalar("age", Hibernate.LONG)              .addScalar("birthday", Hibernate.DATE)              .addScalar("empNo", Hibernate.STRING)              .setString(0, empName)              // 将结果集映射为EmpBean对象              .setResultTransformer(Transformers.aliasToBean(EmpBean.class)).list();  

String hql = "from Attendance att where att.employeeid = ? and att.date =? "; List<Attendance> list = this.getHibernateTemplate().find(hql, new Object[] { employeeid, workDay }); if (null != list && !list.isEmpty()) { return list.get(0); } 

String queryString = "FROM Attendance a WHERE a.employeeid=? AND DATE_FORMAT(a.date,'%Y-%m')=DATE_FORMAT(?,'%Y-%m') ORDER BY a.teamname"; Query queryObject = getSession(). createQuery(queryString); queryObject.setParameter(0, id); queryObject.setParameter(1, date); return queryObject.list(); 

Session session = getSession(); session.clear(); getSession().saveOrUpdate(transientInstance); 

startBatch()的用法

 

public class LocalDaoImpl extends SqlMapClientDaoSupport implements LocalDao {     public void insertBuNaTaxBatLst(final PaginatedList list)     {          getSqlMapClientTemplate().execute(new SqlMapClientCallback() {                 public Object doInSqlMapClient(SqlMapExecutor executor)                         throws SQLException {                     executor.startBatch();                     // do some iBatis operations here                     for(int i=0,count=list.size();i<count;i++)                     {                            executor.insert("insertBuNaTaxBatLst", list.get(i));                         if (i % 50 == 0) {                             System.out.println("----" + i);//没有意义只为测试                         }                     }                     executor.executeBatch();                     return null;                 }             });     }