Hi everybody

I need help with setting my HQL selection query.

I have a Map collection in my queried entity foo:
foo.bar<barKey, barValue>

Now, in my HQL i need to search specific fields of barKey with parameter and return all foo's that hold the bars that have the correct value.

So my HQL looks like this:


But that doesn't work! I keep getting:


At the beginning i thought that maybe it's because i don't alias the index(b), so even though i don't need to return it, i added it just for investigation to the select clause:


However, that didn't work too. It couldn't relate to the field under ib. It is as if it can't work with the map key at all, only the map values, which is odd.

The HQL reference demonstrates:


Does this work for anyone? how can i work with the map key to search in its fields?

Thanks,
Yuval

I've solved this problem using a theta-style join:



Unfortunately any regular join-based solutions failed for me.

If anyone knows another approach that uses actual joins, please share.

Yuval

Look on hibernate tests (HQLTests)- you will find how to work with MAP joins explicit and implicit:

public void testDuplicateExplicitJoinFailureExpected() throws Exception {
//very minor issue with select clause:
assertTranslation( "from Animal a join a.mother m1 join a.mother m2" );
assertTranslation( "from Zoo zoo join zoo.animals an join zoo.mammals m" );
assertTranslation( "from Zoo zoo join zoo.mammals an join zoo.mammals m" );
}

// TESTS THAT FAIL ONLY ON DIALECTS WITH THETA-STYLE OUTERJOINS:

public void testIndexWithExplicitJoin() throws Exception {
//TODO: broken on dialects with theta-style outerjoins:
// steve (2005.10.06) - this works perfectly for me on Oracle8i
assertTranslation( "from Zoo zoo join zoo.animals an where zoo.mammals[ index(an) ] = an" );
assertTranslation( "from Zoo zoo join zoo.mammals dog where zoo.mammals[ index(dog) ] = dog" );
assertTranslation( "from Zoo zoo join zoo.mammals dog where dog = zoo.mammals[ index(dog) ]" );
}

public void testOneToManyMapIndex() throws Exception {
//TODO: this breaks on dialects with theta-style outerjoins:
// steve (2005.10.06) - this works perfectly for me on Oracle8i
assertTranslation( "from Zoo zoo where zoo.mammals['dog'].description like '%black%'" );
assertTranslation( "from Zoo zoo where zoo.mammals['dog'].father.description like '%black%'" );
assertTranslation( "from Zoo zoo where zoo.mammals['dog'].father.id = 1234" );
assertTranslation( "from Zoo zoo where zoo.animals['1234'].description like '%black%'" );
}

public void testExplicitJoinMapIndex() throws Exception {
//TODO: this breaks on dialects with theta-style outerjoins:
// steve (2005.10.06) - this works perfectly for me on Oracle8i
assertTranslation( "from Zoo zoo, Dog dog where zoo.mammals['dog'] = dog" );
assertTranslation( "from Zoo zoo join zoo.mammals dog where zoo.mammals['dog'] = dog" );
}