1. Стратегия Single Table:

HQL: from CatalogItem
SQL: select * from CATALOG_ITEM where ITEM_TYPE='BOOK'

HQL: from MovieItem
SQL: select * from CATALOG_ITEM where ITEM_TYPE='MOVIE'

2. Статегия table per class
HQL: from CatalogItem
SQL: select c.ITEM_ID, c.NAME, m.ITEM_ID, m.GENRE, b.ITEM_ID, b.ISBN 
  from CATALOG_ITEM c 
   left outer join MOVIE_ITEM m on (c.ITEM_ID = m.ITEM_ID)
   left outer join BOOK_ITEM b on (c.ITEM_ID = b.ITEM_ID)
   
HQL: from MovieItem
SQL: select * from CATALOG_ITEM c 
  inner join MOVIE_ITEM m on (c.ITEM_ID = m.ITEM_ID)
  
3. Стратегия table per concrete class 
HQL: from CatalogItem
SQL: 
select ITEM_ID, NAME, GENRE, NULL ISBN, 'MOVIE' ITEM_TYPE 
   from MOVIE_ITEM
union all
select ITEM_ID, NAME, NULL GENRE, ISBN, 'BOOK' ITEM_TYPE 
   from BOOK_ITEM
   
HQL: from MovieItem
SQL: select * from MOVIE_ITEM