Think of the small database we used in our lab exercise - Products and Suppliers. Briefly describe how this database observes any two of the four design principles outlined above.
1. Divides your information into subject-based tables to reduce redundant data.
In our lab exercise, there are two database tables which is products and suppliers. It is not effective and easy to view and compare the information from two separate tables. However, we can join the information from two tables into one. For example, we need to compare the price of certain items that each supplier offers. We need to use the field of ‘product name’, ‘selling price’ etc in products table and the ‘company name’ etc in supplier table. By joining the information, it is easy for us to compare the information, make analysis and certain decision.
2. Accommodates your data processing and reporting needs.
We can use database management system for making a meaningful report by grouping and sorting data. For example, we can group the information by product name, to see which suppliers can offer a cheaper price, and then we can sort the data from cheapest price to the most expensive. Afterwards, the information we needed can be seen clearly. Database management system is useful for creating these reports to present a big-picture overview, highlighting main facts and trends.
About ME
- Law Siu Yee, Cherry
- I love travelling. I wish I could travel around the world..or at least most of the countries.. I believe you wouldn't learn more by reading than traveling~!!
Hi Cherry, when you wrote - " It is not effective and easy to view and compare the information from two separate tables. " - this is true. However, relational databases store information in separate tables because each table is only supposed to focus on a single subject. When it's time to view the data, the Report Wizard or the Query Wizard can be used to select only the records and fields that are needed, and group/sort them according to the user's preferences.
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