How to Limit Query Results in JPQL and HQL?

Limiting Queries in JPQL and HQL

In JPQL or HQL, it is possible to limit the number of results returned by a query using the setMaxResults method. However, older versions of Hibernate allowed users to use a syntax similar to MySQL's LIMIT clause.

Support for Limit in Older Versions of Hibernate

In Hibernate 2, it was possible to perform limit queries using the following syntax:

SELECT * FROM a_table ORDER BY a_table_column DESC LIMIT 0, 20;

This syntax allowed users to specify an offset and a maximum number of results to return.

Removal of Limit Support in Hibernate 3

However, with the introduction of Hibernate 3, the LIMIT clause was no longer supported in HQL. According to a response on the Hibernate forum, this feature was never intended to be a part of HQL.

Using setMaxResults() for Result Limiting

To limit the number of results returned by a query in Hibernate 3, users must use the setMaxResults method:

Query query = session.createQuery("FROM ATable ORDER BY aTableColumn DESC");
query.setMaxResults(20);
List<ATable> resultList = query.list();

This method takes an integer value as an argument, specifying the maximum number of results to return.

Conclusion

In conclusion, the LIMIT clause is not supported in JPQL and HQL in Hibernate 3 and later versions. Instead, users must utilize the setMaxResults method to limit the number of results returned by their queries.

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