Despite The Object-oriented Principles That Are Enshrined In The

Despite the object-oriented principles that are enshrined in the object-oriented data model, there is a prevailing lack of standards and there are no standardised data access methods. Hence, those who may want to use the object oriented data model will have to establish a common method for access which can be complex. In spite of this it will be possible for the college bookshop application designers to provide a standard method for online data access to those who may want to purchase online. Objects can, however, be complex things to deal with and to program resulting in longer learning curves associated with the implementation of an object-oriented data models in a database application which will be required for the college bookshop application. The online application designers will also have to be careful to ensure that the use of the object-oriented data model does not slow down the online transactions. Because the object-oriented model's complexity can be substantially greater then that of the relational model, therefore, substantial operating system overheads, system resource requirements and hardware requirements can result in a slower system. [Rob 2002]; [Lisbeth 1998]
Because of the complexities that can be handled by the object-oriented data model and that fact that even today a lot of installed relational database systems exist, there is a tendency to reserve the object-oriented data models for the relatively sophisticated scientific and engineering applications. The wide use of the relational model tends to support a transition to the object-relational model rather then the object-oriented model. Hence, there is a tendency for the increasing use of the object-relational data model in the business applications arena where more semantics need to be included in the data model. However, the support that is provided to objects in the object-relational data models is considered to be insufficient especially in regard to support for objects, classes, inheritance, polymorphic methods amongst others. The object-relational data model is a synthesis of the relational and the object-oriented data model. It cannot be considered to be a stepping stone for upgrading the relational models into the object-oriented models which hold some promise for the future. Oracle 8i is an object-relational database and has been in wide use in the business sector which serves to illustrate the point. The relational data model is becoming obsolete because for complex data types such as SGML documents which are in wide use in the world today, the performance of every relational database will have to be enhanced tenfold, something which cannot be contemplated. Relational databases are generally not suited for the object oriented data which is likely to be found in use today because the number of tables becomes too large and the performance drops to an unacceptable level.