Inheritance enables you to share attributes between objects such that a subclass inherits attributes from its parent class. OracleAS TopLink provides several methods to preserve inheritance relationships, and enables you to override mappings that are specified in a superclass, or to map attributes that are not mapped in the superclass. Subclasses must include the same database field (or fields) as the parent class for their primary key (although the primary key can have different names in these two tables). As a result, when you are mapping relationships to a subclass stored in a separate table, the subclass table must include the parent table primary key, even if the subclass primary key differs from the parent primary key.
Composition is a term that comes from object oriented design. It is a relationship in which a number of parts comprise a whole, and these parts can only be part of one whole.
There is no direct translation of this concept to database design, but there are some situations in the database world that represent the concept of composition.
zakki aap diagram banany kaleay konsa software use karty hen?????
Bohat Easy Assignment hy mainay solve b kr li hy
bta daina kaafi nahe hota janab idea share karo gi to humyn pata chaly ga na ....!!
han han copy case lagwa lun main share kar ke ?? good
fatima sis i just need idea of solution.so plz snd me ur soln as an idea.thanx
zaki bhai apse sirf idea mang rahe hain.
Idea manga ha solution to nai manga zaki ne,,,
Samjne men galti lag gai ha ap ko......