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Sanad78

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using inheritance in object oriented database

hi all,
my thesis in oodb and specifically in inheritance and its problems
1. which products you preferred to work in, which have full oo featurs (Like slq server, Oracle, DB2, db4o) and why ?
2. how the inheritance work in selected product
3. the internal structue of inheritace (how classes related togother and inheritance done)
4. any related documents, papers, slides discuss this article (new one)

i know how oo works in oopl, and i know in the past full oodb not supported in any one
and its covered in ORDB
i thiks oracle ver 9,10 support oo and db4o ver6.3 ,,, but what about sql server 2005

with bist regards
sanad
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Sanad78

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i found this note from Comparing SQL Server 2005 and DB2 8.2: Focus on Development Productivity
SQL Server Technical Article, Published: July 2005

" DB2 UDB structured types can use object-oriented concepts such as inheritance and dynamic method dispatch. You define inheritance hierarchies by using the "UNDER" keyword in the CREATE TYPE statement. Dynamic method dispatch refers to the fact that methods of the base type can be reimplemented in derived types; at runtime, control will be dispatched to the appropriate method implementation depending on which type is used.
Support of specific functionality above the user-defined type functionality is provided in DB2 UDB 8.2 through an Extender architecture. Extenders may include user-defined types, user-defined functions, special tools, support applications, and APIs.
 
While SQL Server UDTs can be structured types or simple types in theory, it is not recommended to use UDTs for data that contains more than a single fact. For example, even though a date can be represented as month, day, and year, a date represents a single fact. SQL Server UDTs are meant to extend the scalar type system, not to implement structured types. SQL Server UDTs do not support inheritance or dynamic method dispatch when invoked from Transact-SQL. You can use UDTs as columns, but SQL Server has no concept of typed tables, typed views, or references to types.
 "
this mean there is applying for oo featurs like inheritance in oodb ,,, but how ,, i dont kow
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hi all
this site have many answers
http://www.odbms.org/vendors.html
 i will try db4o database using .Net and then discuss the results
thanx