Creating and running queries If you (Hp web site) have a
Creating and running queries If you have a JavaBean with seller and description properties, you can call the setProperties() method to bind the query parameters. For example, you can pass query parameters in an instance of the Item class itself: Item item = new Item(); item.setSeller(seller); item.setDescription(description); String queryString = “from Item item” + ” where item.seller = :seller and” + ” item.description like :desccription”; session.createQuery(queryString).setProperties(item); The setProperties() binding matches names of JavaBean properties to named parameters in the query string, internally calling setParameter() to guess the Hibernate type and bind the value. In practice, this turns out to be less useful than it sounds, because some common Hibernate types aren t guessable (temporal types, in particular). The parameter binding methods of Query are null-safe. So the following code is legal: session.createQuery(”from User as u where u.username = :name”) .setString(”name”, null); However, the result of this code is almost certainly not what you intended! The resulting SQL will contain a comparison like USERNAME = null, which always evaluates to null in SQL ternary logic. Instead, you must use the is null operator: session.createQuery(”from User as u where u.username is null”); Using positional parameters If you prefer, you can use positional parameters instead in Hibernate and Java Persistence: String queryString = “from Item item” + ” where item.description like ?” + ” and item.date > ?”; Query q = session.createQuery(queryString) .setString(0, searchString) .setDate(1, minDate); Java Persistence also supports positional parameters: String queryString = “from Item item” + ” where item.description like ?1″ + ” and item.date > ?2″; Query q = em.createQuery(queryString)
In case you need affordable webhost to host your website, our recommendation is ecommerce web host services.