Differences Between OODB Approaches

• Programming environment: much more closely coupled in

OQL/ODL than in SQL3.

• Changes to objects are done via the programming language in

OQL, and via SQL statements in SQL3.

• Role of relations: still prominent in SQL 3
  • Row types are really tuples, ADT’s describe attributes.
  • In OQL: sets, bags and structures are fundamental.

• Encapsulation: exists in OQL; not really supported by row types

in SQL3, but are supported by ADT’s.

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