On Fri, Mar 26, 2010 at 12:21 PM, Alexander Klimetschek <[email protected]> wrote: > On Fri, Mar 26, 2010 at 15:34, Rami Ojares <[email protected]> wrote: >> Early in the seventies Ted Codd published relational model as an improvement >> over the hierarchical model that had been used for data storage until then. >> >> So why do we still need a hierarchical model for data storage? > > In addition to what others have said already: a major requirement for > going from files to RDBMS in the 70s was the big cost of storage back > then. Hence normalization was considered important, and the relational > model made the best use of the disk space available. > > But nowadays this is different, so "denormalization" is ok. It makes > reads faster. And it is absolutely needed for large databases that > span multiple servers.
Perhaps, OT, but wouldn't we still say that if data integrity is very important, then we still would prefer a well normalized RDBMS to a object oriented persistence mechanism? > > Regards, > Alex > > -- > Alexander Klimetschek > [email protected] >
