如何使用 Hibernate Named Query (HQL) 在 MYSQL 的时间戳字段中搜索当前日期？

Question

我尝试使用以下方式传递日期但无法成功。 dateAnswered 是将日期存储为 2017-09-13 00:00:00 的字段。

谁能告诉我哪里出错了：

方式一：设置参数

@NamedQuery(name = "findAnswar", query = "SELECT a FROM Answar a WHERE (a.dateAnswered = :currentDate )"

Try 1: 
super.em.createNamedQuery( "findAnswar" , Answar .class ).setParameter( "currentDate", new Date() ); //Not receive any data

Try 2: 
Date date = new Date();
date.setHours(0);
date.setMinutes(0);
date.setSeconds(0);
super.em.createNamedQuery( "findAnswar" , Answar .class ).setParameter( "currentDate",  date) //Not receive any data

方式2：设置内置参数

@NamedQuery(name = "findAnswar", query = "SELECT a FROM Answar a WHERE (a.dateAnswered = current_date() )") //NOT WORKS

It works if i do add Temporal to getter:

@Column(name = "DATE_ANASWERED")
@Temporal(TemporalType.DATE)
 public Date getDateAnswered () {
  return dateAnswered ;
}

BUT IT GIVES another issue : Caused by: org.hibernate.HibernateException: Wrong column type in db.ANSWAR for column DATE_ANASWERED. Found: datetime, expected: date

 @NamedQuery(name = "findAnswar", query = "SELECT a FROM Answar a WHERE (a.dateAnswered = current_date )") //NOT WORKS - JPA errors

即使在 Stackoverflow 的先前答案中，我也找不到任何相关的解决方案。任何人都可以仅使用命名查询来帮助修复相同的问题吗？

Answer 1

能够通过对命名查询进行以下更改来实现它，并且效果非常好：

"SELECT a FROM Answar a WHERE cast(a.dateAnswered as date) = current_date()

由于基础类型是日期时间，所以我们需要将其转换为日期才能使用 current_date()

Answer 2

您需要指定时间类型。

方式 1

super.em.createNamedQuery("findAnswar", Answar.class)
     .setParameter("currentDate", new Date(), TemporalType.TIMESTAMP);

方式 2

@Column(name = "DATE_ANASWERED")
@Temporal(TemporalType.TIMESTAMP)
    public Date getDateAnswered () {
    return dateAnswered ;
}