Hibernate Framework HQL and Criteria API 3

Question 1

Which HQL function counts all rows in a query result?

Accepted Answer

count(*)

Answer

HQL supports the count() aggregate function just like SQL to count the number of matching rows.

Question 2

What is the purpose of pagination in Hibernate queries?

Accepted Answer

To retrieve a subset of results using setFirstResult() and setMaxResults()

Answer

Pagination in Hibernate is implemented by calling setFirstResult() for the offset and setMaxResults() for the page size on a Query.

Question 3

Which HQL statement is used to update entity data?

Accepted Answer

UPDATE EntityName SET field = value WHERE condition

Answer

HQL supports bulk UPDATE statements using the UPDATE keyword followed by the entity name and SET clause.

Question 4

What does 'SELECT DISTINCT' do in HQL?

Accepted Answer

Removes duplicate results from the query output

Answer

DISTINCT in HQL eliminates duplicate entity instances from the query result set, just as in SQL.

Question 5

Which HQL keyword is used to perform an inner join between two entities?

Accepted Answer

JOIN

Answer

HQL uses the JOIN keyword to perform joins between related entities based on their mapped associations.

Hibernate Framework Practice Test