Relational Database Model :: essays research papers

Comparing and Contrasting the Relational Database Model and OO ModelThe comparisonal selective informationbase poser is based upon tables or relations. In this model, the physical implementation of the database is rattlebrained away from the user. Users query the database using a high-level query phraseology, such as SQL. The relations are made up of newspaper columns, which have headings indicating the arrogate tallyed by that column. Tables have key studys, which can be employ to identify unique records. Keys relate tables to distributively(prenominal) other. The rows of the relation are besides called tuples, and there is one tuple component for all(prenominal) attribute or column in that relation. A relation or table name, along with those relations attributes, stigma up the comparative schema. Relational Database models are server-centric.When purpose a Relational Database, you essential create a table for each entity type, choose or invent a primordial key f or each table add foreign keys to represent one-to-many relationships create new tables to represent many-to-many relationships define referential integrity constraints evaluate schema quality and make necessary improvements and choose appropriate data types and value restrictions for each field (if necessary).The real power of relational systems lies in the ability to perform coordination compound queries over the data. Relational systems are well understood, and can be passing optimized in terms of queries, scalability, and storage. There is a uniqueness of table rows and primary keys, as well as ease of implementing future data model changes flexibility and maintainability. To build an effective and efficient application in the relational model, the developer must have a comprehensive knowledge of the tables, and any relationships among them. design oriented database management systems are viewed as an alternative approach to meet the demands of more complex data types. The n eed to handle complex object-centric data as the main data element is the driving force posterior intent Oriented database models. These systems attempt to extend Object Oriented computer programming languages, techniques, and tools to provide a means to support data management tasks. Object Oriented models are client centric. Object Oriented databases uses attributes containing object identifiers to let out objects that are related to other objects.When designing an Object Oriented model, you must first determine which classes require forbidding storage define persistent classes represent relationships among persistent classes and choose appropriate data types and value restrictions for each field.Object Oriented database models approach from the opposite direction (a programming language itself) to solve the problem of handling complex data types.