This assignment is an attempt to present a position paper about the pros and cons of a database management system (DBMS) for a new a newly established multi-campus Mpokeleshi University library in Muchinga province of Zambia. It further gives sufficiently clear arguments to enable the vice-chancellor make an informed decision on the way forward. The paper will first define the major concepts under review before outlining the pros and cons of a database management system (DBMS) and finally give sufficiently clear arguments to enable the vice-chancellor make an informed decision on the way forward.
DEFINITIONS OF MAJOR CONCEPTS
To begin with are the definitions of major concepts under review and these are pros and cons, and database management system (DBMS). According to the oxford university dictionary, pros and cons mean advantages and disadvantages or arguments for and against something. A database management system (DBMS) on the other hand can be broken down and be defined as single concepts as follows: ‘data’ are the raw facts or figures which are processed to get the information. A database is a collection of data stored in a standardized format, designed to be processed, shared by different users and may have single or multiple tables organized in rows and columns.
Therefore, a database management system (DBMS) can be defined as “ a software that defines a database, stores the data and supports a query language, produces reports, and creates data entry forms”, (Laudon, 2000:221). Others have defined a database management system as a complex set of software programs that controls the organization, storage, management, and retrieval of data in a database.
ADVANTAGES OF DATABASE MANAGEMENT SYSTEMS
Database management system (DBMS) is a central system which provides a common interface between the data and the various front-end programs in the application. It also provides a central location for the whole data in the application to reside. Database management system (DBMS) has several advantages and among them includes minimal data redundancy: since the whole data resides in one central database, the various programs in the application can access data in different data files. Therefore, data present in one file need not be duplicated in another file thus reducing data redundancy which in turn leads to better data consistency (O’brien, 2003).
The other notable advantage of database management system (DBMS) is data integration: since related data is stored in one single database, enforcing data integrity is much easier. Moreover, the functions of the database management system (DBMS) can be used to enforce the integrity rules with minimum programming in the application programs. Data sharing is another advantage of a database management system (DBMS): Related data can be shared across programs since the data is stored in a centralized manner. Even new applications can be developed to operate against the same data since several users can access and use the same data for different purposes, provided they are authorized users, as you might be aware that databases are normally protected by passwords to avoid unauthorized users from accessing and or manipulating such database content (Date, 2003:268-276).
Enforcement of standards and better controls are also achieved due to the centralized nature of the system. Standards in the organization and structure of data files is required, and is also easy in a data system since it is one single set of programs which is always interacting with the data files. Another advantage which gives database management system (DBMS) a plus is application development ease: the application programmer need not build the functions for handling issues like concurrent access, security, data integrity to mention but a few, the programmer instead only needs to implement the application business rules.
This hence brings in application development ease because addition of additional functional modules becomes easier than in file-based systems. Nijssen, (1976:158) outlines that data independence is yet another merit of database management system (DBMS): He outlines that data independence is isolating an upper level from the changes in the organization or structure of a lower level. For example, if changes in the file organization of a data file do not demand for changes in the functions in the database management system (DBMS) or in the application programs, data independence is achieved. He further defines that data as immunity of applications to change in physical representation and access techniques.
The provision of data independence is one of the major objectives of database systems due to the architectural nature of a database management system (DBMS) which can be viewed as a three level system comprising the internal or physical level where the data resides, the conceptual level which the level of the DBMS functions and last but not the least the external level which is the level of application programs or the end users. Due to the centralized nature of a database management system (DBMS) maintenance cost is reduced thus accounting for yet another advantage of DBMS.
It is generally acceptable that it costs much less to create a system of smaller computers with the equivalent power as a single large and expensive computer. This makes it more cost-effective for corporate divisions and departments to obtain separate and less expensive computers. It is also much more cost-effective to add workstations to a network than to update a mainframe system. Another dimension of cost reduction is taking advantage of economies of scale. It is generally argued that the cost of processing and maintenance of individual and geographically remote systems may be expensive as opposed to processing and maintaining a centralized system which may be much economical because the technical expertise required for running such a complex system can be centralized or concentrated at one site hence reducing the cost which could have been incurred for running separate and geographically remote systems (Conolly, 1997).
DISADVANTAGES OF DATABASE MANAGEMENT SYSTEMS
Despite the various advantages of database management systems (DBMS), it is worth pointing out that it has its own shortcomings or disadvantages or rather challenges, and some of them include confidentiality, privacy and security: It is worth noting that when information is centralized and is accessed by a huge number of users remotely, the possibility of abuse are often more, as opposed to a conventional data processing system, thereby compromising the levels of confidentiality, privacy and security. Therefore, to reduce the chance of unauthorized users from accessing and abusing sensitive information, it is necessary to take technical, administrative, and possibly legal measures to curb such abuse if a database management system (DBMS) is to continue to serve its intended purpose of informing, entertaining and indeed educating the masses (Laudon, 2004:223).
Similarly, since the database is accessible to many users remotely, adequate controls are needed to control unauthorized users from updating data on the database if data quality and data integrity are to be maintained. Additionally, with the increased number of users accessing data directly, there are greater opportunities for the users to damage the database unless there are suitable controls put in place to ensure data accessibility and quality is not compromised. Enterprise vulnerability is yet another challenge of a database management system (DBMS). It is worth noting that centralizing all the data of an enterprise in one database may mean that such a database becomes an indispensable and a reliable resource.
Therefore, the survival of the enterprise may depend on reliable information being available on its database all the time. If the risk of possible damage is left unchecked by overlooking adequate maintenance and upgrading, the whole enterprise therefore becomes vulnerable to higher impact of failure. According to (Conolly, 1997:689), complexity and cost account for another demerit of a database management system (DBMS). It is common knowledge that a complex conceptual design process needs multiple external well qualified staff with the necessary technical expertise, who are in most instances scarce and possibly expensive to hire.
The fact that a complex system requires additional and or new hardware and software for maintenance and or upgrading which are expensive even worsens the prohibitive cost of running an effective database management system (DBMS) for small enterprises as they normally struggle with cost justification for making such huge investments in the infrastructure, or backup and recovery in cases of damage and or failure of the system.
JUSTIFICATION FOR A DATABASE MANAGEMENT SYSTEM FOR A MULTI-CAMPUS UNIVERSITY LIBRARY
Despite the above outlined disadvantages of database management systems (DBMS), it is worth noting that the advantages of DBMS outweigh the disadvantages and some of the weaknesses should be viewed as mere challenges of database management systems (DBMS) as opposed to being disadvantages because they can be mitigated. For example, the challenges of cost of running a complex database management system can be mitigated by cutting the relative cost of data transmission across the network by introducing local access.
It may be much more economical to partition the application and perform the processing locally at each site or rather at each at each campus library of the multi-campus university. Furthermore, the challenge of prohibitive cost of kick starting and or running a complex database management system (DBMS) can also be minimized by the application of what is known as the “Grosh’s law” of economics which argues that: computing power is calculated according to the square of the cost of the equipment: three times the cost could provide nine times of power, which is why it costs much less to create a system of small computers with the equivalent power of a single large computer.
This makes it more cost-effective for corporate divisions and departments to obtain small separate computers, which in this case can be equated to running a small and cost-effective library networks at each site of the multi-campus university (Conolly, 1997:688). He goes on to argue that a distributed database management system (DDBMS) could be ideal for a multi-campus university library as opposed to a centralized database management system (CDBMS) due to improved availability and improved reliability.
On the one hand, improved availability is enhanced in the sense that unlike in a centralized database management system (CDBMS) where a computer failure can terminate the operations of the database management system (DBMS), conversely, a failure at one site of a distributed database management system (DDBMS) or a failure of a communication link making same sites inaccessible does not render the entire system inoperable. It is however impressive to note that in this type of a system, if a single node fails, the system may be able to reroute the failed node’s request to another site hence improving availability to various users of a multi-campus university library.
On the other hand, improved reliability is also achieved because data may be replicated so that it exists in more than one site, similarly, the failure of a node or a communication link does not necessarily make the data inaccessible to various users of a multi-campus university library. Last but not the least, in a multi-campus library setup, data can physically reside nearest to where it is most often accessed, thus providing users with local control of the data that they interact with. This results in local autonomy of the data allowing users to enforce locally the policies regarding access to and or manipulation of their database management system (DBMS).
In conclusion, database management systems (DBMS) have continued to make data arrangement, storage, access and retrieval much easier than it used to be in the olden days. With the emergency of the relational model of database management systems (which is a software that is used to create and use a relational database-which in turn is a database that conforms to the relational model, and refers to a database’s data and schema), much of the big challenge associated with handling large and complex databases has been reduced. With the continued and advances in research, it is highly expectant that more and advanced database management products will be availed on the market to improve on the existing ones hence further minimizing the challenges of running a complex database management system.