I had an HQL query like this:
Query query = session.createQuery("from User as user where user.joined!=null order by user.joined desc");
How do I set a variable User property as the sort order for my query? My solution:
String order = "user.joined";
Query query = session.createQuery("from User as user where user.joined!=null order by :order desc").setString(开发者_JAVA技巧"order", order);
does not give an ordered query result.
Use a criteria query.
List<User> users = session.createCriteria(User.class)
.add(Restrictions.isNotNull("joined"))
.addOrder(Order.desc(order))
.list();
Or, using HQL:
Query query = session.createQuery("from User as user where user.joined!=null order by user." + order + " desc");
In your second query, when you use this method call:
[Hibernate Query object].setString("order", order)
You are trying to bind a column name as a parameter, which is not possible.
What is a parameter (for this concern) follows the SQL parameters definition, wich is also the parameter definition used in JDBC API PreparedStatement.
To dynamically build a query (besides it's parameters) there are other solutions like the ones pointed by Matt Ball. You could also see Using a prepared statement and variable bind Order By in Java with JDBC driver.
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