In Simple JDBC (with no Hibernate) we can do batch select by changing only place holder, like this
PreparedStatement stmt = conn.prepareStatement(
"select id, name from users where id = ?");
for ( int i=0; i < 10; i++ ) {
stmt.setInt(i); // or whatever values you are trying to query by
// execute statement and get result
}
How we can do it in Hibernate?
Hope this helps you out,
String hql = "from Users s where s.id= :userId";
for(int i=0; i< 10;i++){
List result = session.createQuery(hql)
.setParameter("userId", i)
.list();
}
This is the most common and user friendly way. It use colon followed by a parameter name (:example) to define a named parameter
String hql = "from Student s where s.registerNumner = :registerNumner";
List result = session.createQuery(hql).setParameter("registerNumner", "12345").list();
The setParameter() method is smart enough to discover the parameter data type of bind variable.
You can use setString to tell Hibernate this parameter date type is String.
String hql = "from Student s where s.registerNumber = :registerNumber";
List result = session.createQuery(hql).setString("registerNumber", "12345").list();
This feature is great ! You can pass an object into the parameter binding. Hibernate will automatic check the object’s properties and match with the colon parameter.
Student student = new Student();
Student.setRegisterNumber("12345");
String hql = "from Strudent s where s.registerNumber = :registerNumber";
List result = session.createQuery(hql).setProperties(student).list();
You can use positional parameters also.
String hql = "from Student s where s.registerNumber = ? and s.studentName = ?";
List result = session.createQuery(hql).setString(0, "12345").setParameter(1, "Harshad").list();
But it’s vulnerable to easy breakage because every change of the position(i.e. index) of the bind parameters requires a change to the parameter binding code
You can use following way for batch select
String hql = "from Users s where s.id= :userId";
List finalResult = new ArrayList();
for(int i=0; i< 10;i++){
List result = session.createQuery(hql).setParameter("userId", i).list();
finalResult.addCollection(result );
}
