Hibernate Mapping

In this tutorial we will discuss Hibernate mapping.

Hibernate Mapping

Hibernate Mapping

In this tutorial we will discuss Hibernate mapping.

Hibernate Mapping :


Hibernate mapping is of different types. database tables mapping ,O/R mapping etc.
Here we are discussing Object/Relational mapping. In general, you can do O/R mapping in XML file.
You can also do mapping by using annotations.
Types of mapping :There are four kinds of mapping you can done through hibernate-

  1.  One-to-One mapping
  2.  One-to-Many mapping
  3.  Many-to-One mapping
  4.  Many-to-Many mapping

One-to-One Mapping : One-to-One relationship is single-valued in both the directions. In one to one relationships occurs when one entity is exactly related to single occurrence in another entity.
You can say , each row in table A is linked to only one row of B .

Example :If we take two table as employee and department. Then the relation one head of department manages one department and each department has only one head.
you can see ,there is one to one relationship from both side.

One-to-Many Mapping : One-to-Many relationship is single valued in one side and multi valued in other side. It means one entity is related to many occurrence in another entity.
You can say, each record of one table A is linked to multiple records in another table B.

    Example :
  •  A car and its parts. Each part belongs to one car and one car has multiple parts.
  •  Employee and phone number, One employee can have many phone numbers but phone number belongs to only one employee.

Many-to-One Mapping : Many-to-one relationship is multi valued in one side and single valued in other side. It means many occurrence of a entity is related to one occurrence in another entity.
You can say, multiple records of one table A is linked to one record in another table B.

Example : Employee and address. Many employee live in same house so many employee belongs to one address.

Many-to-Many Mapping : Many-to-Many relationship is multi valued in both side. It means many occurrence of a entity is related to many occurrence in another entity.
You can say, multiple rows of one table A is linked to multiple rows in another table B.

Example : A student can have many subjects .In the same way one subject can have many students so here is many-to many relationship.

Tutorials

  1. Why hibernate is used?
  2. Hibernate Native SQL Example
  3. Hibernate Update Query
  4. Hibernate Delete Query
  5. Hibernate Count Query
  6. Writing First Hibernate Code
  7. Running First Hibernate 3.0 Example
  8. Hibernate Book
  9. Understanding Hibernate O/R Mapping
  10. Using Hibernate to generate id incrementally
  11. Hibernate Query Language
  12. Preparing table for HQL Examples
  13. Writing ORM for Insurance table
  14. HQL from clause Example
  15. Hibernate Select Clause
  16. HQL Where Clause Example
  17. Hibernate Architecture
  18. HQL Group By Clause Example
  19. hibernateTemplate-Order Results
  20. Hibernate Criteria Query Example
  21. Hibernate How To
  22. Hibernate Quickly
  23. Hibernate 3.1.2 Released
  24. HQL Order By Example
  25. Hibernate 3.1.3 Released
  26. Hibernate 3.1.1 Released
  27. Introduction to Hibernate 3.0
  28. Complete Hibernate 3.0 and Hibernate 4 Tutorial
  29. Hibernate Avg() Function (Aggregate Functions)
  30. Hibernate Max() Function (Aggregate Functions)
  31. Hibernate Min() Function (Aggregate Functions)
  32. Hibernate Criteria Expression (eq)
  33. Hibernate Criteria Expression (lt)
  34. Hibernate Criteria Expression (le)
  35. Hibernate Criteria Expression (gt)
  36. Hibernate Criteria Expression (ge)
  37. Hibernate Criteria Expression (and)
  38. Hibernate Criteria Expression (or)
  39. Hibernate Projections (rowCount or countDistinct)
  40. Hibernate Projection Count