HQL按日期查询查询（Java + NetBeans）

本文介绍了HQL按日期查询查询（Java + NetBeans）的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 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）;

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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);

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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());