Re: An object-oriented network DBMS from relational DBMS point of view
Date: 12 Mar 2007 10:43:17 -0700
On 10 mar, 06:02, JXStern <JXSternChange..._at_gte.net> wrote:
> If you follow the normalization rules for 3NF, you constrain the
> object structures and instances, how about that?
yes, but I can break 3NF in my OODB. I can dynamically add some attribute to some node. It is not reflects on all other rows, stored in a table and don't reflects on table interface. It is very effective way to solve EAV problems. Each instance can have its own unique set of attributes, up to 4G
> And if you don't,
> then you give up the ability to run SQL efficiently, or at all,
> against the database.
I don't provide SQL. I am using C# instead of SQL. Some declarative query language which looks like SQL is in implementation now but not yet available for download.
> Vtbl sucks
May be, but very fast in implementation.
> But if those pointers do not follow normalization rules, you lose the
> underlying RDBMS. Is anything lost by using keys?
I am really want to lose RDBMS and not needed it at all ))) But I want be able do all what RDBMS do. If it will be implemented differently - it is ok. I developing network DB not an relational. The idea of this post - network DBMS can do all what can do RDBMS and even more and better.
> That's not news, that an unconstrained description has constrained
> grammers as a subset, that type 0 grammar has type 1,2,3 grammars as
> "special cases", but the general case does not have some of the
> properties of its simplified, special cases.
Agree. But if some system allows to implement type 0 grammar then also it allow implement constrants and emulate type 1,2,3 grammars but not vice versa.
WBR, Dmitry Received on Mon Mar 12 2007 - 18:43:17 CET