如何使用“日期对象"从“领域数据库"中获取数据? [英] How to get data from **Realm database** using **date object**?

问题描述

我尝试了一些领域查询，但没有得到我想要的结果

I have tried some realm queries but not getting that result which I want

让我们以下面的表为例(领域表):

let's consider below table for example(Realm table):

id    Name  DateTimeStamp

1      A    2017-01-01 08:00:00
2      B    2017-01-01 15:00:00
3      C    2017-01-02 08:00:00

现在，我想要所有与日期"2017-01-01"匹配的记录.因此，在这种情况下，我应该从realm表中获得2条记录.

Now I want all those records which match the date "2017-01-01".so for this case I should get 2 records from realm table.Right now I am not getting any record.

有关信息，"DateTimeStamp"列的数据类型为"Date".是的，我需要将日期和时间都存储在数据库中，如表所示.

For information "DateTimeStamp" column datatype is "Date".and yes I need to store date and time both in the database as you can see on the table.

我尝试过的查询是:

 long cnt = realm.where(ReservationObject.class).equalTo("DateTimeStamp",dateObject).count();

请帮助我... 预先感谢...

Please help me with this... Thanks in advance...

推荐答案

您需要为2017-01-01 00:00:00和2017-01-02 00:00:00设置Date对象并在它们之间进行查询.

You need to set up Date objects for 2017-01-01 00:00:00 and 2017-01-02 00:00:00 and query inbetween.

Calendar calendar = Calendar.getInstance();
calendar.set(Calendar.DAY_OF_MONTH, 1); // make sure month stays valid
calendar.set(Calendar.YEAR, 2017);
calendar.set(Calendar.MONTH, Calendar.JANUARY);
calendar.set(Calendar.HOUR_OF_DAY, 0);
calendar.set(Calendar.MINUTE, 0);
calendar.set(Calendar.SECOND, 0);
calendar.set(Calendar.MILLISECOND, 0);
Date jan1 = new Date(calendar.getTimeInMillis());
calendar.set(Calendar.DAY_OF_MONTH, 2);
Date jan2 = new Date(calendar.getTimeInMillis());

然后

realm.where(ReservationObject.class)
     .greaterThanOrEqualTo("DateTimeStamp", jan1)
     .lessThan("DateTimeStamp", jan2)
     .findAll()

这篇关于如何使用“日期对象"从“领域数据库"中获取数据?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！