An Electronic Database - Essay Example

Databases An electronic database is an organized collection of data in a digital form, to achieve a properly working database. A specific user requirement needs to be well elicited before the design and development takes place. These requirements are in two categories; functional and non functional. The functional ones are. First, it should allow users to create new trainers and topics; secondly, it should allow creation deletion of users. It should also allow only authorized users to make changes in the data stored example the trainers should not have the privilege of making changes on schedules and topics, it should allow easy production of standardized reports. The developer should also specify the data type stored in the database. One should also specify the type of activity to be acted upon each and every screen. Workflows in any system determine the order in which tasks should be carried out and therefore in the database system we should also specify the workflows of the system. One should also specify who can enter delete or update data in the database system. The system should also meet applicable regulatory requirements in the organization. Non functional includes the ability to recover and back up data in the database to prevent loss during failure. Others include data security, privacy issues, privacy issues and minimum hardware and software requirements of the system that the database will run on. Non functional requirements also include performance and configuration requirements such as expected business volumes and system responsiveness. It should also ensure that the system is available for use for when needed. It should also ensure proper utilization on the resources of the computer i.e.; CPU cycles, disk space, memory, bandwidth. The database system should be portable across different platforms the system should also enforce. Finally it should ensure high performance. Certain tasks or features are more critical than others. The system should also be capable of maintaining its performance all through its lifetime. The database systems should also allow for reuse in that part of it can be used to design new systems. Finally, the database should also have a capability of handling error conditions gracefully. An electronic database provides a highly efficient way of storing data. Its advantages are considerable. It saves time; a properly designed database running on a powerful server can be searched through remarkably easily and within an extraordinarily short time. It also helps to save time lost during transfer of physical data from one office to another. Secondly, a database offers more security, file cabinets can be compromised, stolen, accidentally destroyed, or be misplaced. Databases add another level of security to critical information. A database can not only be stored in a remote and inaccessible facility unaffected by devastating events such as fire or robbery, but it can also be protected using passwords and a username. It locks out any unauthorized person from accessing and performing operations on stored data. Electronic database offers data consistency and harmony, unlike the manual does not allow information that does not match in the same field, for example, dates and names in the same field. An electronic database, unlike manual databases also offers room for scalability; one can add columns, redesign and add tables without losing any data. It also makes sharing of data easier as compared to manual database. Several authorized trainers or staff can be given access to the server where the database resides unlike in the manual database where the files are moved from one working station to another. It also allows many users to access it simultaneously. Despite the above named advantages, an electronic database also has some disadvantages, First, the initial capital of designing and developing a database is costly and need skilled personnel to do it. Also the cost of purchasing a server to host the database is also immense and this bars small organizations from using electronic databases. Secondly, it requires some skilled staff to man and maintain it which’s also costly and therefore making it difficult to use. It is also vulnerable to risk such as hacking especially if there is a connection to the internet the cost of securing the database from such a risk is also high and required well trained personnel to perform it. Finally, it involves an extensive cost in moving from a manual database to an electronic database and initial training to users before they can use it. Referential integrity is a concept employed in database development that ensures that relationships between tables remain harmonized and consistent. It preserves the relationships previously created between the data tables during the data updates. There exists a connection among all entities in a database via one or more attributes. Applying the referential integrity rules, one ensures that no any change or update that can be effective that affect the relations already defined between tables, Example, no any value of foreign keys can enter the database and does not have a corresponding primary key value in the related table, it also reduces bug in applications, in that the declarations of referential integrity are more error free than the equivalent programming scripts or codes. In essence, such declarations make use of the already tried and tested general-purpose code in the engine of a database engine, rather than coding the same logic on a case-by-case basis which can easily lead to errors, it also ensures data integrity and consistency based on a primary key and foreign key, Querying inconsistent databases remains a broad and difficult problem and leads to errors in report generation. Ensures quality of data references across the multiple application programs that may access a database. Referential integrity has helped in reducing data redundancy in the database for data under the attribute primary key cannot be duplicated. Finally referential integrity is easy to implement especially using database management systems such as access and mysql since one does not have to write the code since as they exist in the database engine. It ensures that the soundness of the relationships remains intact. A trainer can have many courses and a course can only be taught by one lecture. Visio Diagrams Entry Relationship Diagram Indicating a One -to-Many relationship. It defines that one instructor is associated with many courses. i.e. An instructor can teach many courses and many courses can be taught by a single instructor. Instructors Employee_ID_No First_Name Last_Name Department Email 201201 Mcdonald Franklin Engineering mfranklin@university.edu 201202 Mary Leaky Computer Science Mleaky@university.edu 201203 Andrew Breason Engineering Abreason@university.edu 201204 Brook Forestor Communication Skills Bforestor@university.edu 201205 Achipolopolo Andrew Computer Science Aandrew@university.edu Courses Table Course_Number Course_Name Trainer_Emp_No Train_Location 10001 Database Administration 201201 Lecture 1 10002 Computer Application 201202 Lecture Hall 5 10003 Information System 201202 Computer Lab 10004 Object Oriented Programming 201203 Computer Lab 10005 System Analysis And Design 201204 Lecture Hall 7 Work cited 1. Business Database Systems (2008).Oxford University press. Peter Rob, Carlos Coronel. 2. Database processing(2007).oxford university press: David Kroenke, Kathleen A. Dolan. 3. Database Management Systems(1998).Cambrige University press.: S. K. Singh. 4. Database system concepts. (1991). McGraw-Hill (6th ed.). Washington D.C: AbrahamSilberschatz. 5. Readings In Database Systems(2010). Dorlon Kindersley(India)PV.ldt: Joseph M.Hellerstein, Michael Stonebraker. Read More