Essay Example on 3-Phase Database Design: Conception to Implementation

Introduction

Database design consists of three primary phases, namely, physical, logical, and conceptual design. The conceptual design is the process of database design with no physical implementations such that there is no thought of software, hardware, or other physical entities. The phase is more of the thoughtful design process and is an important model that helps to aid in the logical design (Hernandez, 2013). Moreover, the logical design imitates the conceptual model as it also has no representation of the physical entities. However, the model depends on the database management system (DBMS) knowledge that should be used. It incorporates data from the conceptual model then tests and normalizes the data for accuracy (Hernandez, 2013).

Is your time best spent reading someone else’s essay? Get a 100% original essay FROM A CERTIFIED WRITER!

Save 25%

Additionally, the physical database design incorporates the logical design and adds the assigned database management system for the enterprise, then designs the system's physical layout such as constraints and relationships, creating tables, and to set the security protocols. Therefore, the three database design phases must always work together so that the database management system begins from a specific concept to a desired physical design before it is implemented (Hernandez, 2013).

Explain how the bottom-up design approach differs from the top-down design approach

The top-down approach often divides a complex algorithm or problem into modules or multiple smaller parts. The depicted modules are always further decomposed until the fundamental program is the resulting module that can be understood and cannot be decomposed further. After attaining a specific modularity level, the modules decomposition is ceased (Borenstein et al., 2004). Thus, the top-down approach is the stepwise breaking process of a large module of a program into smaller and simpler modules to code and efficiently organize a program.

The control flow in the approach is often in the downward direction and is always implemented by using functions in the C programming language. On the other hand, the bottom-up approach operates opposite to the top-down approach. Initially, it comprises of designing of the fundamental system parts that are further combined to make the higher-level module (Thiran & Hainaut, 2001). The modules and submodules integration into the higher-level module is performed repeatedly until the desired complete algorithm in attained. The bottom-up approach often functions with abstraction layers.

Moreover, one can depict that the submodules of the top-down approach are solitarily analyzed. In contrast, the bottom-up approach examines what data should be encapsulated, implying the concept of information hiding (Thiran & Hainaut, 2001). Also, in communication, the top-down approach is not required, while the bottom-up approach needs a certain communication amount. The top-down approach also contains redundant information, while in the bottom-up approach, redundancy can always be eliminated.

For the programming languages, the procedural or structure oriented programming like the C program follows the top-down approach. On the contrary, object-oriented programming languages such as Java and C++ follows the bottom-up approach. The top-down approach is mainly used in debugging, implementation of codes, creation of test case, and module documentation, while the bottom-up approach is mainly used in testing (Borenstein et al., 2004).

Which approach do you believe should be used to design a simple database with a relatively small number of attributes, and why?

The top-down approach should be used to design a simple database with a relatively small number of attributes. The reason is that the approach will always avoid attempting chaos in designing a system all at once (Borenstein et al., 2004). Moreover, because planning and implementation management of information systems are always complex, trying to get every subsystem in place and running it all at once might be a failure. Also, the top-down approach enables separate teams of systems analysis to work on different but parallel and necessary subsystems that save time. Thus, using teams for subsystems design is well suited to a full quality approach of assurance (Thiran & Hainaut, 2001).

Additionally, the top-down approach avoids a primary problem connected with the bottom-up approach as it curbs systems analysts from getting mired in detail that they might get confused about what the system should be doing. Total management of quality and the top-down approach often work together. The top-down approach often provided the groups of systems with a ready-made user division into task forces for the subsystems. The depicted set up task forces then serve a dual function as circles of quality for the information system management.

The desired quality assurance structure will then be in place. It will be an effective motivation for getting the subsystems to complete the goals of the system that are essential to the involved users (Thiran & Hainaut, 2001). Nevertheless, the top-down approach is always characterized by an extensive research and planning phase that results in the database development. The action is often used on the first creation of a database as a high view of the level of the whole database with all requirements known. Thus, there is always full visibility of the change effects on the relationships and the entire database. Also, the top-down approach is always more coherent, with fewer ways of operation and less redundancy. It specifies the requirements without concentrating or worrying about implementation (Borenstein et al., 2004).

References

Borenstein, E., Sharon, E., & Ullman, S. (2004, June). Combining top-down and bottom-up segmentation. In 2004 Conference on Computer Vision and Pattern Recognition Workshop (pp. 46-46). IEEE. Doi: 10.1109/CVPR.2004.314

Hernandez, M. J. (2013). Database design for mere mortals: a hands-on guide to relational database design. Pearson Education. demoivre.org/courses/CSE382/labs/lab4/dbdesign.pdf

Thiran, P., & Hainaut, J. L. (2001). Interoperability of legacy databases: a combined top-down and bottom-up approach. Doi: 10.17169/refubium-22762