Chapter 4
How a database differs from a spreadsheet
-more powerful and complex than a spreadsheet, with the ability to handle multiple types of data and link them together. A database has defined field types. A database uses a standardized query language (such as SQL). Can hold much larger amounts of data.
Why is it important to define the data type of a field when designing a relational database?
A data type tells the database what functions can be performed with the data. To define the data type is so that the proper amount of storage space is allocated for the data.
Explain in your own words how the data component relates to the hardware and software components of information systems.
Data is processed by the hardware via software. A database is software that runs on the hardware. Hardware stores the data, software processes the data.
What is data mining?
Data mining is the process of analyzing data to find previously unknown trends, patterns, and associations in order to make decisions.
What are the characteristics of a relational database?
Database in which data is organized into one or more tables. Each table has a set of fields, which define the nature of the data stored in the table. A record is one instance of a set of fields in a table. All the tables are related by one or more fields in common.
What is metadata?
Metadata is data about data. It refers to the data used to describe other data, such as the length of a song in iTunes, which describes the music file.
Name a database you interact with frequently. What would some of the field names be?
The student can choose any sort of system that they interact with, such as Amazon or their school's online systems. The fields would be the names of data being collected, such as "first name", or "address".
When would using a personal DBMS make sense?
When working on a smaller database for personal use, or when disconnected from the network.
Describe what the term normalization means.
1) reduces duplication of data between tables and 2) gives the table as much flexibility as possible.
Data
Data are the raw bits and pieces of facts and statistics with no context. Data can be quantitative or qualitative.
Information
Information is data that has been given context.
Knowledge
Knowledge is information that has been aggregated and analyzed and can be used for making decisions.
What is the difference between quantitative data and qualitative data? In what situations could the number 42 be considered qualitative data?
Quantitative data is numeric, the result of a measurement, count, or some other mathematical calculation. Qualitative data is descriptive. The number 42 could be qualitative if it is a designation instead of a measurement, count, or calculation. For example: that player's jersey has number 42 on it.
Name three advantages of using a data warehouse.
i. The process of developing a data warehouse forces an organization to better understand the data that it is currently collecting and, equally important, what data is not being collected. ii. A data warehouse provides a centralized view of all data being collected across the enterprise and provides a means of determining data that is inconsistent. iii. Once all data is identified as consistent, an organization can generate one version of the truth. This is important when the company wants to report consistent statistics about itself, such as revenue or number of employees. iv. By having a data warehouse, snapshots of data can be taken over time. This creates a historical record of data, which allows for an analysis of trends. v. A data warehouse provides tools to combine data, which can provide new information and analysis.
