Name : Leung Chuk Kwan

Student ID : 98518901

Course : GEO 2105 Geographic Information System

Lecturer : Prof. Hui Lin

Tutor : Mr. Joshua Hui

There are several qualitative criteria that we commonly use to determine the fitness of data. They are reliable and accurate, current, relevant, timeliness, complete and precise. It means that data must be in a format that ensure the handling of data, no matter maintenance, transmission, classification, resampling, retrieving, and updating should be in convenient way. Also, it is better if the metadata, the data of the data was kept, for the users to retrieve, and determine their suitability for a certain purpose.

The data quality is largely based on the three generic measures of quality, namely accuracy, precision and error, and the concept of uncertainty that is associated with using data of unknown quality. Of course there are a certain elements for each of the three measures, however, this assignment aimed on the discussion of importance of data quality and database management system. It is common known that the more accurate the primary data, the more reliable result would come out. Therefore, the importance of data quality is well known. But one may not realize that some error may produce during the operation of data, therefore, the way of managing data is important as well.

On the other hand, database management needs consistent checking to prevent misuse and degradation of information. The objectives of database management system are to permits various methods of access, to store data independent of application, control access to data, to facilitate data modification, and to minimize data redundancy. In short, it should provide security, integrity, synchronization, physical data independence, and the minimization of redundancy.

Therefore, the way of organizing, processing of data has a significant effect on the corresponding result. It should produce a physically independent database, which can be used by different projects. Otherwise redundancy of data would just waste storage space. Updating and modification of data would ensure the data integrity. One can foresee that the relevant database management system is definitely influential in producing a useful and accurate result.

Considering the functions of a database management system, it is obvious to see that the software application performed might directly influence the outcoming result of a research. However, one should not deny the quality of inputted data, "Garbage in, Garbage out", the accurate data input would certainly produce relatively accurate result. But therefore it is difficult to determine which one is important than the other, the statement is not valid enough.