Answer to Question #324344 in Databases | SQL | Oracle | MS Access for jes

Question

1.1 State the five main steps of the DBLC.

1.2 For each step stated above in Question 1.1. State and explain the activities that are done for each step.

Answer 1

The main steps of the DBLC are

Requirements analysis

Logical design

Physical design

Implementation

Monitoring, modification, and maintenance

Requirements Analysis is the first stage in the DBLC.

It is the most labor-intensive for the database designer. This stage involves assessing the informational needs of an organisation so that a database can be designed to meet those needs.

During the first part of Logical Design, a conceptual model is created based on the needs assessment performed in stage one. A conceptual model is typically an entity-relationship (ER) diagram that shows the tables, fields, and primary keys of the database, and how tables are related (linked) to one another. The tables sketched in the ER diagram are then normalized. The normalisation process resolves any problems associated with the database design, so that data can be accessed quickly and efficiently.

The Physical Design stage has only one purpose and that is to maximize database efficiency. This means finding ways to speed up the performance of the RDBMS. Manipulating certain database design elements can speed up the two slowest operations in an RDBMS: retrieving data from and writing data to a database.

During the implementation stage of the DBLC, the tables developed in the ER diagram (and subsequently normalized) are converted into SQL statements. These SQL statements are then executed in the RDBMS to create a database. By this stage in the database life cycle, the System Administrator has installed and configured an RDBMS.

A successfully implemented database must be carefully monitored to ensure that it is functioning properly and that it is secure from unauthorized access. The RDBMS usually provides utilities to help monitor database functionality and security.

Database modification involves adding and deleting records, importing data from other systems (as needed), and creating additional tables, user views, and other objects and tools. As an organisation grows, its information system must grow to remain useful.