DBMS

Data Analysis and Design

Data Analysis and Design

Task 1

Advantages and Dis-advantages of Database Models and Architectures

Hierarchical Database Model

A hierarchical database is a type of management system that stores information in a hierarchical structure that links records in a tree structure where a parent node of information can have several child nodes. In the same way a relationship can be established between sibling nodes In this case the tree-shaped structure becomes a structure in the form of directed graph (Choi et.al, 2010).). The major advantage of a hierarchical model is the existence of management systems and tested databases using the hierarchical model as the basic structure. Another major advantage of this model is its relative simplicity and ease of use and the familiarity of user's data processing hierarchy. However, there are several drawbacks of this model which includes; the hierarchical commands tend to be procedural, because the writing of the structure, insertion and deletion become extremely complex. Implementation of too many relationships can result in redundancy.

Relational Database Model

The relational model is a data model, suitable to the underlying model of a System Manager Database (DBMS) that is based on the principle that all data is stored in tables (or, mathematically speaking, relationships). Among the main advantages of the relational model there is independency of the data, multiple data view, and greater security to access the data. Along, with marked reduction in development activity, particularly for extracting data for reports and queries specific user. The drawback of this model includes hardware overheads which occur due to the implementation complexities and the security of physical data storage from the users. Another major drawback of this model is its ease of use which often leads to the development and implementation of a poorly designed DBMS (Ronnback et.al, 2010). The main feature of a relational database is that the data in tables (tables), academic relations (relations) called, are organized, which are largely independent of each other. A table / relation are a two-dimensional structure consisting of rows (rows) and columns (columns). All entries in a particular column have the same meaning (eg, titles, subtitles). Each column represents a specific attribute (attribute) of the object represented by the table. Each row contains the attribute of a single object in the table. The order of the rows and columns in a table is irrelevant.

Network Model

The network model organizes data using two basic constructions, records and sets. Records contain fields (which can be organized hierarchically, as in the COBOL programming language.) Assemblies (not to be confused with mathematical sets) define one too many relationships between records: one owner, many members. This model can prove to be immensely beneficial to use for the database administrator as it enables the database administrator to represent redundancy in data more efficiently than in the hierarchical model. The operations of the network model are navigational in style: a program maintains a current position, and navigates from one record to another by following the relationships in which the record participates ...