low performance in Query (how to EXPLAIN SELECT ... in hiber

[grzegorz.knapczyk]

I have written an entity bean wrapper to the existing TABLE in PostgreSQL.

create table pr_base{
 id varchar(100) no null, -- PK
 channel varchar(4),
 airdate date,
 (...)
}


CREATE INDEX idx_airdate_channel
 ON pr_base
 USING btree
 (airdate, channel);

I have defined a business method to find all records by channel and airdate.

public List findByDateChannel(String airdate, String channel){
 return em.createQuery("FROM PrRecord pr WHERE airdate = :airdate and channel = :channel")
 .setParameter("airdate", airdate)
 .setParameter("channel", channel)
 .getResultList();
}

However the method is very slow, like it wouldn't use idx_airdate_channel?
Is it possible to force hibernate to explain query, i.e. use "EXPLAIN SELECT ..."?