The purpose of this literature review is to define database management systems and evaluate existing online booking systems. The differences between traditional and online reservation systems are discussed in this chapter. In addition, features that are essential to an online booking system are highlighted. The purpose of this structure is to provide an overview of the project context before going into more detail about project specifics.
1.1.1 Database Management Systems
This section of the literature review will introduce the concepts of databases and database management systems. Functions provided and components of database managements systems are discussed. Thereafter, a few advantages and disadvantages of DBMS are highlighted.
Management of data has evolved throughout the years with the continuous development of the internet. Organisations have had to move from traditional methods of managing data to the use of web-based databases to store and organise their data in a reliable and secure manner (Gray 1996).
A database management system (DBMS) is software dedicated to facilitate the maintenance and use of large collections of data (Ramakrishnan 1998).
The need for appropriate data management systems used by organisations is driven by the expanding amount of information handled in day-to-day operations of businesses. This is where database management systems come into use as they alleviate the amount of work required to manage data and extract useful information when required (Ramakrishnan 1998).
The database management system should perform functions listed below as stated by Garcia-Molina et al. (2009):
? Granting users the option to make new databases and dictate the logical design of the data
? The ability for users to query and modify data
? Support the efficient storage of large collections of data
? The database should be able to recover from failures in a timely manner
? Permit several users to access data at the same time from different locations.
1.1.2 File Systems vs DBMS
In order to justify the use of a database management system, this section of the report will demonstrate the context of the project and the need for a DBMS. The aim of this project is to design a database with a suitable interface that can handle an accommodation agent. This includes considering multiple properties with different or multiple property owners. The database should be capable of controlling property occupations and vacancies, online booking and finance controls. Several users will access this data. Queries concerning the data should be answered in a timely manner, modifications to the data on every occasion must be updated accordingly and some parts of the data such as financial data require restrictions (Ramakrishnan 1998).
This scenario can be handled in two ways namely, using a collection of operating system files or a DBMS. The use of a collection of operating system files creates a number of problems such as:
the need for storage devices to store all the data
identifying data requires a specific method
special programs must be created to solve data queries
Managing modifications made to the data by several users.
On the other hand, a DBMS is expected to simplify these tasks as data can be managed in an efficient manner (Elmasri and Navathe 2010).
1.1.3 Transaction Management
A transaction is “any one execution of a user program in a DBMS” (Ramakrishnan and Gehrke 1998). Considering the database created in this project, it is possible that several users will be accessing information about different available properties and booking viewings. Therefore, it is expected that the DBMS will be able to arrange all the user requests in a manner that does not cause conflicts.
According to Ramakrishnan (1998), the use of database management systems to handle data has the following advantages:
The DBMS allows the application programs to be independent from details of data representation and storage.
Efficient data access
A DBMS facilitates the efficient storage and retrieval of data.
Data integrity and security
Integrity constraints access controls can be enforced on the data. Certain classes of uses will only be able to view specific data.
Management of data can be centralised in order to reduce redundancy.
Concurrent access and crash recovery
The DBMS can regulate data access and protect users from the effects of system failures. (not paraphrased)
Table 1: Advantages of DBMS
There are some limitations of using a DBMS. These are listed below (source: TutorialCup 2015):
Complexity: the software required to handle multiple functionalities is complex.
Memory: due to the complexity and number of functionalities supported by DBMS, a large amount of memory is required for it to run smoothly.
Centralized system: all the data is stored on a centralised system, therefore if any failure occurs, all users will be affected.
1.2 Online Booking Systems
An online booking system or online reservation system is software that facilitates the interaction between a potential customer and a business website. This system enables the creation of reservations and payment for services without human interaction. There are several features involved in these transactions, regardless of the industry, such as selecting a desired date, time (if necessary) and making a payment online (Bookinglive 2017).
Online booking systems are widely used in businesses that can also make them available to their customers, if applicable. These applications can be used for various purposes such as booking journeys (on any mode of travel such as train, bus or air) and making hotel reservations on a mobile app or web application or in some cases, both. In the UK, for example, the main modes of public transport include railway, road and air. The advancement of technology has encouraged the sophistication of reservation systems. The one thing they have in common is the provision of online booking systems widely accessible by the public. For example, the National Rail Service provides three main methods of booking tickets; on an app, on their website and customers can also book their tickets at a train station before their journey. This offers flexibility as customers have a more than one way of making a travel reservation