Compare date only (without time) in JPA2 (JPQL)

Im trying to compare Calendars with JPA2. The query looks somewhat like that:

TypedQuery<X> q = em.createQuery("select r from Record r where r.calendar= :calendar", X.class);
Calendar c = foo(); // setting fields and stuff
q.setParameter("calendar", c);

This, however, compares the date + time. I want to know if MM:DD:YYYY is equal and do not care about the time. Is there a nice way to do that in JPA2 or do I have to crea开发者_如何转开发te a native query?

I tried setting HH:MM:SS:... to zero before saving it in the db but I don't know if this is very wise, regarding time zones and daylight saving and stuff.

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q.setParameter("calendar", c, TemporalType.DATE)

You can pass the TemporalType.DATE to setParameter method to truncate the date+time.

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There is no mention of DateTime functions allowing to do that in the spec of JPQL, but you could always cheat and do

select r from Record r where r.calendar >= :theDayAtZeroOClock and r.calendar < :theDayAfterAtZeroOClock

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Mysql and H2 compatible comparison of dates ignoring time part:

`@Query("SELECT DISTINCT s " +
        "FROM Session s " +
        "JOIN s.movie m " +
        "WHERE m.id = :movie AND CAST(s.time AS date) = CAST(:date AS date) " +
        "ORDER BY s.time")
List<Session> getByMovieAndDate(@Param("movie") Long movie, @Param("date") LocalDateTime date);`

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When using an Oracle database, you can use the trunc function in your JPQL query, e.g.:

TypedQuery<X> q = em.createQuery("select r from Record r where trunc(r.calendar) = trunc(:calendar)", X.class);

See also https://cirovladimir.wordpress.com/2015/05/18/jpa-trunc-date-in-jpql-query-oracle/

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I had to use date_trunc on the where clause:

    TypedQuery<X> q = em.createQuery("select r from Record r where date_trunc('day',r).calendar= :calendar", X.class);
Calendar c = foo(); // setting fields and stuff
q.setParameter("calendar", c, TemporalType.DATE);

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In Hibernate 6 and above, you can use date_trunc(text, timestamp) to truncate the timestamp more precisely, for example:

date_trunc('hour', timestamp) to truncate the timestamp up to the hour (no minutes and no seconds).