Repository Design

Database Design

Scenario

Currently a college uses a non-computerised database program to store this information about the students: spin class, surname, first identity, guardian's identity, address, scholar's date of birth, sexuality, sport house, emergency-contact contact number, mailing brand, list of themes offered, and subjects when the student is enrolled. The machine takes up a large number of space, has its own duplicated entries some of these with mistakes and it is time consuming to locate. The school hopes to expose a relational-database management system to overcome these kinds of problems.

Current school info storage and retrieval program (the pre-computer database system)

В„h University staff, educators and business office staff would be the users from the database. В„h Database used to track most details of students in the college. В„h A lot of data will be stored. Someone record is necessary for each student. В„h Lots of duplication exists as details of subjects provided by the school happen to be duplicated in individual student records. В„h Data is organised in alphabetical buy on pupil names within just years. В„h Data is stored in a number of filing cabinets.

Positive aspects

В„h quick to find details of a student in the event year and surname are known В„h data is definitely stored in a central protect location

В„h original origin material is stored in trainees file.

Drawbacks

В„h slow to find information on students when ever surname and year aren't known В„h data safe-keeping takes up a lot of area

В„h little number of personnel can access records at one time

В„h info is duplicated.

Stages of development of the computerised relational database program

The newest computerised relational database program will be designed in the next stages:

В„h analysis

В„h design

В„h implementation

В„h maintenance

Examination

In this stage the current product is analysed to look for the functions that performs and those that it is unable to perform. Indirect and direct users of the new program are interviewed to determine what they require through the new system. The advices to the fresh system, the processes it is to conduct and the results from the system are clearly defined. A advice is made regarding the type of new system that is to be required to satisfy the identified needs.

During the evaluation stage, here i will discuss determined:

В„h current storage place of pupil records should decrease В„h an easily update-able back-up of scholar records is needed, В„h one staff member is usually to be responsible for the administration of the system, В„h unnecessary replication of data shall be avoided,

В„h most teaching staff, office personnel and the Main need to have entry to the data source simultaneously enjoy access only is required В„h reports just like roll category lists, subject matter class lists, lists of sporting residences, student contact details and family members mailing lists should be easily made.

To satisfy these requirements, a relational database system has been suggested. A relational database can be " a database in which data is organised in a series of relationships, or two-dimensional tables, where the columns (attributes) represent info fields, plus the rows (tuples) represent documents. Linking of data between documents in different data files is done by means of a key discipline. "

The relational model was chosen in preference to a flat file-system as the needs of users would not become met with a flat file. A set file is definitely " a form of database exactly where all of the info is found in one file". For all of the details to be held in one desk, every college student record would require info to be without cause duplicated, bringing out redundant data. For example , every student record would require information about the topics the student is enrolled in and these subject details will be duplicated through the flat document. This duplicated data increases the space needed by the computer system to procedure and retail outlet the data. Additionally, it leads to possible problems with the integrity of...