How to convert HQL to SQL Query programmatically (without logging)

Question

I am executing the following HQL and it is executing properly

String hql = \"FROM Employee\";
Query query = session.createQuery(hql);
List results = query.list(         


        

Answer 1

Hibernate Types

Starting with the 2.9.11 version, the Hibernate Types open-source project offers the SQLExtractor utility that allows you to get the SQL query from any JPQL or Criteria API query, no matter you are using Hibernate 5.4, 5.3, 5.2, 5.1, 5.0, 4.3, 4.2, or 4.1.

Get the SQL statement from a JPQL (HQL) Query

Let's assume we have the following JPQL (HQL) query:

Query jpql = entityManager.createQuery("""
    select 
       YEAR(p.createdOn) as year, 
       count(p) as postCount 
    from 
       Post p 
    group by 
       YEAR(p.createdOn)
    """, Tuple.class
);

With Hibernate Types, extracting the Hibernate-generated SQL query is as simple as that:

String sql = SQLExtractor.from(jpql);

And, if we log the extracted SQL query:

LOGGER.info("""
    The JPQL query: [
        {}
    ]
    generates the following SQL query: [ 
        {}
    ]
    """,
    jpql.unwrap(org.hibernate.query.Query.class).getQueryString(),
    sql
);

We get the following output:

- The JPQL query: [
    select    
        YEAR(p.createdOn) as year,    
        count(p) as postCount 
    from    
        Post p 
    group by    
        YEAR(p.createdOn)
]
generates the following SQL query: [
    SELECT 
        extract(YEAR FROM sqlextract0_.created_on) AS col_0_0_,
        count(sqlextract0_.id) AS col_1_0_
    FROM 
        post p
    GROUP BY 
        extract(YEAR FROM p.created_on)
]

Notice that we unwrapped the JPQL (HQL) Query to the Hibernate org.hibernate.query.Query interface which provided the getQueryString method we can use to log the associated JPQL query string.