Student Number: 200202650
School of Engineering & Computing
Course: HNC Business Information Technology
Module: Database Fundamentals
Module Reference: CSH1025
Tutor: Adrian Stevart
Date: Monday, 21 June 2004
| |ix |
|User Requirements |1 |
|Normalization |1 |
|Forms and there uses ...view middle of the document...
1. User Requirements
• Database to be used by recruitment company called Finders
• Finders work for a number of external clients
• All types of employment
• Agency get a fee for each vacancy filled
• Upon instruction by client, Finders place advert in suitable publication
• Details of applicants, jobs, clients, publication details to be stored on database
• System must be created so that Mail merge can be used to automate interview letters
• Reports and Queries to be used to interrogate the database
To achieve all the objectives outlined within the Database scenario and to be able to manipulate the data and to present it in such a way as to be useful for decision-making, a structured process needs to be adhered to. Normalization is a data technique that attempts to capture all the system needs to store and to organize the data into an efficient structure, and one that doesn’t fall down when operational. With the Finders Employment agency in mind this will enable the data to be organized in such a way that can then be applied to creating a Database that works efficiently. This process can start from a list of seemingly disorganized data items collected during the fact-finding stages of analysis. After normalization has been applied and grouped data within logical groups (entities), this then creates a data model, as seen in [1.1] on Appendix A.
• First normal form demands that each entity has an identifying key that is unique only to that entity. For this purpose I have created a key field, as seen in each and every entity at the end of the attributes list underlined, as seen in [1.2].
• Normalization provides an algorithm for reducing complex data structures into irreducible simple structures. The data that the system needs to store data is organized into its minimal form. Therefore name and address within the APPLICANTS entity and similarly address within the CLIENTS entity have been broken down further. Please see end of respective attributes list for amendments within [1.2].
Please see Appendix B for refined Entity Relationship Diagram.
2. Data validation puts into place further safeguards that ensure that the data input maintains its integrity. It checks that the data is sensible before processing it. An example of a validation rule that could be applied to Finders Employment Agency’s database is a range check, whereupon the data within a form falls between a specified range of values. For example the month of a persons date of birth falls between 1 and 12.
Forms………..what are they good for?
Forms are excellent and user-friendlier for data entry than tables, for example. Forms feel more comfortable. Forms also have facilities for data filtering, automation, and validation beyond that possible using tables or queries alone.
Within the Finders database all forms were linked to an underlying table. Therefore all data...