COMMERCE 2KA3 Chapter Notes - Chapter 6: Data Dictionary, Relational Model, Data Element

• School: McMaster University
• Department: Commerce
• Course: COMMERCE 2KA3
• Professor: Ali Montazemi

Document Summary

Problems of managing data resources in a traditional file environment. Effective systems provides with accurate, timely, relevant and complete information. Bit: smallest unit of data a computer can handle. Represents a single character (letter, #, another symbol) Field: grouping of characters into a word, a group of words, or a complete number. Record: a group of related fields. file: a group of records. Entity: person, place, thing, or event on which we store and maintain information. Encourages each functional area in a firm to develop specialized applications. Each application requires a data file that is likely to be a subset of the master file. This in turn leads to redundancy, inconsistency, processing inflexibility and wasted storage resources. Program data dependence: coupling of data stored in files and the specific programs required to update and maintain those files such that any changes in programs requires changes to the data.