Object Oriented Database Vs object Relational Data

2019-03-17 20:08发布

问题:

I wonder how Object Oriented data modeling is different from Object Relational data modeling?

Is it something like the pluses of both object oriented and relational data modeling were clubbed to achieve object relational data modeling?

cheers

回答1:

Object-Relational data modeling supports some object-oriented concepts, while still supporting some relational concepts:

  • Inheritance -- one table can have an IS-A relationship with another table. Likewise custom data types support inheritance.
  • Distinction between a class and an object (instance of a class) that goes beyond simply the distinction between a table and a row.
  • Custom or complex data types.
  • Relational query language.
  • Referential integrity.

Object-Oriented data modeling is just persistence for objects:

  • Greater support for complex objects.
  • No query language -- you just retrieve individual objects like some giant key/value store.
  • No relational referential integrity -- though you may have one object contain a reference to another object.