Criteria Query Examples

In the last lesson we learnt how to use Criteria Query to select all the records from Insurance table.

Criteria Query Examples

Criteria Query Examples

     

In the last lesson we learnt how to use Criteria Query to select all the records from Insurance table. In this lesson we will learn how to restrict the results returned from the database. Different method provided by Criteria interface can be used with the help of Restrictions to restrict the records fetched from database.


 

 

 

Criteria Interface provides the following methods:

Method Description
add The Add method adds a Criterion to constrain the results to be retrieved.
addOrder Add an Order to the result set.
createAlias Join an association, assigning an alias to the joined entity
createCriteria This method is used to create a new Criteria, "rooted" at the associated entity.
setFetchSize This method is used to set a fetch size for the underlying JDBC query.
setFirstResult This method is used to set the first result to be retrieved.
setMaxResults This method is used to set a limit upon the number of objects to be retrieved.
uniqueResult
  		 This method is used to instruct the Hibernate to fetch and return the unique records from database.

Class Restriction provides built-in criterion via static factory methods. Important methods of the Restriction class are:

Method Description
Restriction.allEq
  		 This is used to apply an "equals" constraint to each property in the key set of a Map
Restriction.between
  		 This is used to apply a "between" constraint to the named property
Restriction.eq
  		 This is used to apply an "equal" constraint to the named property
Restriction.ge
  		 This is used to apply a "greater than or equal" constraint to the named property
Restriction.gt
  		 This is used to apply a "greater than" constraint to the named property
Restriction.idEq This is used to apply an "equal" constraint to the identifier property
Restriction.ilike
  		 This is case-insensitive "like", similar to Postgres ilike operator
Restriction.in This is used to apply an "in" constraint to the named property
Restriction.isNotNull This is used to apply an "is not null" constraint to the named property
Restriction.isNull   This is used to apply an "is null" constraint to the named property
Restriction.le  This is used to apply a "less than or equal" constraint to the named property
Restriction.like This is used to apply a "like" constraint to the named property
Restriction.lt This is used to apply a "less than" constraint to the named property
Restriction.ltProperty This is used to apply a "less than" constraint to two properties
Restriction.ne  This is used to apply a "not equal" constraint to the named property
Restriction.neProperty This is used to apply a "not equal" constraint to two properties
Restriction.not   This returns the negation of an expression
Restriction.or  This returns the disjuction of two expressions

Here is an example code that shows how to use Restrictions.like method and restrict the maximum rows returned by query by setting the Criteria.setMaxResults() value to 5.

package roseindia.tutorial.hibernate;

import org.hibernate.Session;
import org.hibernate.*;
import org.hibernate.criterion.*;
import org.hibernate.cfg.*;
import java.util.*;
/**
 * @author Deepak Kumar
 * 
 * http://www.roseindia.net 
Hibernate Criteria Query Example
 *  
 */public class HibernateCriteriaQueryExample2 {
  public static void main(String[] args) {
  Session session = null;
  try {
  // This step will read 
hibernate.cfg.xml and prepare hibernate for
  // use
  SessionFactory sessionFactory
 = new Configuration().configure()
  .buildSessionFactory();
  session = 
sessionFactory.openSession();
  //Criteria Query Example
  Criteria crit = 
session.createCriteria(Insurance.class);
  crit.add(Restrictions.like("
insuranceName", "%a%")); //Like condition
  crit.setMaxResults(5); //
Restricts the max rows to 5

  List insurances = crit.list();
  for(Iterator it = 
insurances.iterator();it.hasNext();){
  Insurance insurance =
 (Insurance) it.next();
  System.out.println("
ID: " + insurance.getLngInsuranceId());
  System.out.println("
Name: " + insurance.getInsuranceName());
  
  }
  session.close();
  } catch (Exception e) {
  System.out.println(e.getMessage());
  } finally {
  }  
  }
}

Tutorials

  1. Why hibernate is used?
  2. Hibernate Native SQL Example
  3. Hibernate Update Query
  4. Hibernate Delete Query
  5. Hibernate Count Query
  6. Writing First Hibernate Code
  7. Running First Hibernate 3.0 Example
  8. Hibernate Book
  9. Understanding Hibernate O/R Mapping
  10. Using Hibernate to generate id incrementally
  11. Hibernate Query Language
  12. Preparing table for HQL Examples
  13. Writing ORM for Insurance table
  14. HQL from clause Example
  15. Hibernate Select Clause
  16. HQL Where Clause Example
  17. Hibernate Architecture
  18. HQL Group By Clause Example
  19. hibernateTemplate-Order Results
  20. Hibernate Criteria Query Example
  21. Hibernate How To
  22. Hibernate Quickly
  23. Hibernate 3.1.2 Released
  24. HQL Order By Example
  25. Hibernate 3.1.3 Released
  26. Hibernate 3.1.1 Released
  27. Introduction to Hibernate 3.0
  28. Complete Hibernate 3.0 and Hibernate 4 Tutorial
  29. Hibernate Avg() Function (Aggregate Functions)
  30. Hibernate Max() Function (Aggregate Functions)
  31. Hibernate Min() Function (Aggregate Functions)
  32. Hibernate Criteria Expression (eq)
  33. Hibernate Criteria Expression (lt)
  34. Hibernate Criteria Expression (le)
  35. Hibernate Criteria Expression (gt)
  36. Hibernate Criteria Expression (ge)
  37. Hibernate Criteria Expression (and)
  38. Hibernate Criteria Expression (or)
  39. Hibernate Projections (rowCount or countDistinct)
  40. Hibernate Projection Count