Search your topic in Java2share
Home > FAQs
eXTReMe Tracker

Hibernate FAQs

37.What are the benefits does HibernateTemplate provide?
The benefits of HibernateTemplate are :

  • HibernateTemplate, a Spring Template class simplifies interactions with Hibernate Session.
  • Common functions are simplified to single method calls.
  • Sessions are automatically closed.
  • Exceptions are automatically caught and converted to runtime exceptions.

38. How do you switch between relational databases without code changes?
Using Hibernate SQL Dialects , we can switch databases. Hibernate will generate appropriate hql queries based on the dialect defined.

39.If you want to see the Hibernate generated SQL statements on console, what should we do?
By using “show_sql” property of the hibernate configuration file
In Hibernate configuration file set as follows:
<property name="show_sql">true</property>

40.What are derived properties?

The properties that are not mapped to a column, but calculated at runtime by evaluation of an expression are called derived properties. The expression can be defined using the formula attribute of the element.

41.Define cascade and inverse option in one-many mapping?

cascade - enable operations to cascade to child entities.

inverse - mark this collection as the "inverse" end of a bidirectional association.
Essentially "inverse" indicates which end of a relationship should be ignored, so when persisting a parent who has a collection of children, should you ask the parent for its list of children, or ask the children who the parents are?

42 . Explain about transaction file?
Transactions denote a work file which can save changes made or revert back the changes. A transaction can be started by session.beginTransaction() and it uses JDBC connection, CORBA or JTA. When this session starts several transactions may occur.