Questions Unit 2 Pt2520
Unit 2
Homework Questions
Alvaro Ojeda
PT 2520
Instructor
Mrs. Hubbard 1. What is a database requirement?
* The requirements for a logical and physical database vary by size and design parameters. A logical database must be able to access and identify all files within the storage system to operate correctly, whereas a physical database manages a much smaller field of information. Sometimes, a physical database stores only a single file with one value or word in it.
2. What is the primary purpose of a report?
* A document used to display summarized or formatted data.
3. What is the primary purpose of a form?
* A document that is used to gather data.
4. What is the domain of a database?
* This is the focus of the database.
5. What is work shadowing?
* It means following and observing persons as they go through their work routine.
6. What is a candidate key?
* A Candidate Key can be any column or a combination of columns that can qualify as unique key in database. There can be multiple Candidate Keys in one table. Each Candidate Key can qualify as Primary Key.
7. What is a composite key?
* A key that consist of more than one attribute.
8. What is a natural key?
* A key made from one or more of an entity’s “natural” attributes.
9. What are the advantages of a natural key?
* Natural keys prevent duplicate rows, because the attributes are part of the primary key. Any duplicate set of data will be rejected from being inserted by plain primary key logic (unique and not null). This dramatically increases the overall data quality compared to artificial keys.
10. What is a surrogate key?
* An artificially created key, often just auto-incremented numbers
11. What is a stakeholder?
* Anyone with a “stake” in the final product. Anyone who will use or be affected by the database.
12. What is an exception (with regard to a database)?
Homework Questions
Alvaro Ojeda
PT 2520
Instructor
Mrs. Hubbard 1. What is a database requirement?
* The requirements for a logical and physical database vary by size and design parameters. A logical database must be able to access and identify all files within the storage system to operate correctly, whereas a physical database manages a much smaller field of information. Sometimes, a physical database stores only a single file with one value or word in it.
2. What is the primary purpose of a report?
* A document used to display summarized or formatted data.
3. What is the primary purpose of a form?
* A document that is used to gather data.
4. What is the domain of a database?
* This is the focus of the database.
5. What is work shadowing?
* It means following and observing persons as they go through their work routine.
6. What is a candidate key?
* A Candidate Key can be any column or a combination of columns that can qualify as unique key in database. There can be multiple Candidate Keys in one table. Each Candidate Key can qualify as Primary Key.
7. What is a composite key?
* A key that consist of more than one attribute.
8. What is a natural key?
* A key made from one or more of an entity’s “natural” attributes.
9. What are the advantages of a natural key?
* Natural keys prevent duplicate rows, because the attributes are part of the primary key. Any duplicate set of data will be rejected from being inserted by plain primary key logic (unique and not null). This dramatically increases the overall data quality compared to artificial keys.
10. What is a surrogate key?
* An artificially created key, often just auto-incremented numbers
11. What is a stakeholder?
* Anyone with a “stake” in the final product. Anyone who will use or be affected by the database.
12. What is an exception (with regard to a database)?
References: * Hands-On Database -Steve Cogner2012 Pearson Education Inc. * Logical and Physical Database Requirements by Jonathan Lister , Demand Media http://smallbusiness.chron.com. * Surrogate Keys or Natural Keys? By Craig S. Mullins - Posted Sep 11, 2012 - September 2012 Issue http://www.dbta.com/Articles/Columns/DBA-Corner/Surrogate-Keys-or-Natural-Keys-84892.aspx