HQL按日期查询查询（Java + NetBeans） [英] HQL make query searching by date (Java+NetBeans)

问题描述

我有以下问题。我的MySQL数据库中有一张储备表，日期列定义为DATETIME。我需要使用hibernate进行查询，以便在一天内找到所有储备，无论时间如何，只要它是同一个月份和日期，而我正在这样做

  public List< Reserve> bringAllResByDate（Date date）{
 
 em = emf.createEntityManager（）; 
查询q = em.createQuery（SELECT r FROM Reserve r WHERE r.date =：date）; 
 q.setParameter（date，date）; 
  

...

我真的没有知道如何使它比较，并给我指定日期的那些，任何帮助？

解决方案

我希望有数据库不可知的方式将数据时间设置为日期。这通常是我如何处理你的情况。

  Calendar from = Calendar.getInstance（）; 
 Calendar to = Calendar.getInstance（）; 
 
 from.add（Calendar.DATE，-1）; 
 to.add（Calendar.DATE，1）; 
 
查询q = em.createQuery（SELECT r FROM Reserve r WHERE r.date>：dateFrom AND r.date<：dateTo）; 
 q.setParameter（dateFrom，from.getTimeInMillis（））; 
 q.setParameter（dateTo，to.getTimeInMillis（））; 
  

Hi all I have the following issue. I have a table of reserves in my MySQL DB, the date columns is defined DATETIME. I need to make a query using hibernate to find all reserves in one day no matter the hour, just that its the same year month and date, and I'm doing this

public List<Reserve> bringAllResByDate(Date date){

em = emf.createEntityManager();
Query q = em.createQuery("SELECT r FROM Reserve r WHERE r.date=:date ");
q.setParameter("date", date);

...

I really dont know how to make it compare, and bring me just those from the specified date, any help??

解决方案

I wish there were a database-agnostic way of casting datetimes as dates. This is usually how I deal with your scenario.

Calendar from = Calendar.getInstance();
Calendar to = Calendar.getInstance();

from.add(Calendar.DATE, -1);
to.add(Calendar.DATE, 1);

Query q = em.createQuery("SELECT r FROM Reserve r WHERE r.date > :dateFrom AND r.date < :dateTo ");
q.setParameter("dateFrom", from.getTimeInMillis());
q.setParameter("dateTo", to.getTimeInMillis());

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