Is there any way i could use HQL to get the maximum value of columns from multiple tables..

I have a column called modifiedDate in 2 different tables, i would like get max of this, is it possible??

I tried like this..
SELECT greatest(obj1.modifiedDate, obj2.modifiedDate) FROM Object1 AS obj1, Object2 AS obj2 WHERE obj1.id = :id and obj2.object1Id = :id

It didnot work as greatest function is not part of the hibernate??

Any ideas please?

I tried like this to get the list of objects..but this is working only when there is data present in 2 tables. Even if one table has null value then it is returning null because of the cross join.
SELECT new List(obj1.modifiedDate, obj2.modifiedDate) FROM Object1 AS obj1, Object2 AS obj2 WHERE obj1.id = :id and obj2.object1Id = :id

is there any alternate solution? or using using loader on property??