The first hql Program

Use hql to query databases:
Perform the following steps:

1. Obtain the query object

　　　　//1获取query对象        String hql="FROM Employee e where e.salary>?";        Query query=session.createQuery(hql);

2. Bind a parameter (you can bind a location parameter or a name parameter (but it must start with:) or an object parameter)

Location parameters:

        //2绑定参数        query.setInteger(0, 100);

Example of name parameters:

//1. 创建 Query 对象        //基于命名参数.         String hql = "FROM Employee e WHERE e.salary > :sal AND e.email LIKE :email";        Query query = session.createQuery(hql);                //2. 绑定参数        query.setFloat("sal", 7000)             .setString("email", "%A%");

Object parameter example:

  String hql = "FROM Employee e.dept = ? ";         Query query=session.createQuery(hql);  Department dept = new Department();        dept.setId(80);         query.setEntity(2, dept);    

 

3. Query

//3执行查询        List<Employee> emps=query.list();        System.out.print(emps.size());

 

The first hql Program