dbruck@ciss.Dayton.NCR.COM (Don Bruck@ciss.Dayton.NCR.COM) (07/28/89)
In article <81@csnz.co.nz> paul@csnz.co.nz (Paul Gillingwater) writes: >In article <18886@sequent.UUCP> normb@sequent.UUCP (Norm Browne) writes: >>In article <AYknCfy00WB28IU6sk@andrew.cmu.edu> bg0l+@andrew.cmu.edu (Bruce E. Golightly) writes: >>>model. Sometimes the users insist that they want what they want, and you >>>can't do it without breaking the model. We had to write an application >> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ >>>to do this kind of thing a while back. >> Does it strike anyone else that the above kind of >> statement indicates that the relational model is >> not a very accurate depiction of the real world? > >Experience tends to confirm that the relational approach is not >an accurate model for all real-world situations. I could present >an empirical "proof", but I'm not well enough versed in formal >logic to present a rigorous argument for this. ;-) > >It seems "intuitive" to me that an object-oriented OODBMS is better >at mapping real world situations. Further, there are some cases >where a relational approach is very limited, e.g. large text >databases, where a record may contain from a few bytes to several >megabytes. This is where software like BRS/Search, which indexes Object oriented does seem intuitive. So do Relational designs, Hierarchic designs and Batch oriented files, at certain times. The link I put between Relational and Object Oriented models is that if the data is in a Relational mode it can support many objects. In other words, the data portion of an object can be thought of as a join of one or more relations, including only those attributes pertinent to the object. That is the strength and intended objective of relational design - flexibility and extensibility. Finally, the model is only a representation. The implementation of a model should use the processing environment that best suits the problems to be solved. If searching text is important then store text with word-by-word indexing, if transaction speed is of the utmost importance then denormalize around the most important objects or transactions, if versatility is most important use a relational dbms. Use a model to analyze what your users have, use tools to give them what they need. -------------------------------------------------------------------------------- Don Bruck These opinions are my own, but may coincide with and be claimed by my employer.