JPA, Hibernate, Error with convert()

[Chris Boldon]

My database has a table that includes date, which I use as a timestamp, giving me nanosecond precision. However, there is a place in my application where I want to group and select rows by Date only, disregarding time.

Perhaps my query is wrong, but this is what I'm calling:

select count(*), convert(Date,hit.hitDatetime) from Hit hit group by convert(Date,hit.hitDatetime) order by convert(Date,hit.hitDatetime)

I'm trying to get the number of records for each day.

Hibernate is throwing the following error:

org.springframework.dao.InvalidDataAccessApiUsageException: No data type for node: org.hibernate.hql.ast.tree.MethodNode 
 \-[METHOD_CALL] MethodNode: '('
    +-[METHOD_NAME] IdentNode: 'convert' {originalText=convert}
    \-[EXPR_LIST] SqlNode: 'exprList'
       +-[IDENT] IdentNode: 'Date' {originalText=Date}
       \-[DOT] DotNode: 'hit0_.hit_datetime' {propertyName=hitDatetime,dereferenceType=4,propertyPath=hitDatetime,path=hit.hitDatetime,tableAlias=hit0_,className=com.xxx.redirect.model.Hit,classAlias=hit}
          +-[ALIAS_REF] IdentNode: 'hit0_.hit_id' {alias=hit, className=com.xxx.redirect.model.Hit, tableAlias=hit0_}
          \-[IDENT] IdentNode: 'hitDatetime' {originalText=hitDatetime}

Here is the full method in my DAO:

	public List getDailyHitsForPastThirtyById() {
		try {
			final String queryString = "select count(*), convert(Date,hit.hitDatetime) from Hit hit group by convert(Date,hit.hitDatetime) order by convert(Date,hit.hitDatetime)";
			return getJpaTemplate().executeFind(new JpaCallback() {
				public Object doInJpa(EntityManager em)
						throws PersistenceException {
					Query query = em.createQuery(queryString);
					return query.getResultList();
				}
			});
		} catch (RuntimeException re) {
			LOG.error("getRecentGroupedHitsById failed", re);
			throw re;
		}
	}

Any suggestions? Thank you for your time.