PT2520 Unit7Labs Tramil
Mekao Tramil
PT2520
Unit 7 Labs
Lab 7.1
Lab 7.2
Lab 7.3
1. What does redundancy refer to? Redundancy refers to repeating the same data more than once; It occurs in a number of ways such as the data could be repeated over and over again in the same file.
2. What is a primary key? Each table usually has one column designated as a primary key . This key uniquely identifies each row in the table.
3. What is a foreign key? This primary key becomes a foreign key when it is repeated in another table to create a link between the tables.
4. What is SQL language? The programming language used to manipulate data and data objects in a relational database.
5. What are entities? An entity is something that the database is concerned with, about which data can be stored, and which can have relationships with other entities.
6. What are database requirements? This is something a database must do. For instance, it must keep track of tutors and the classes for which they can tutor.
7. What is data integrity? The accuracy and quality of the data.
8. What is a form? What is a report? A form is a document, paper or electronic, that is used to gather data. A report is a document, paper or electronic, used to display summarized or formatted data
9. What is the domain of a database? The focus of the database. If the database is about the tutoring program, its domain is “tutoring.”
10. What is work shadowing? Following and observing persons as they go through their work routine.
11. What are candidate keys? Attributes that could possibly be used as identifying attributes.
12. What is a composite key? A key that consists of more than one attribute.
13. What is referential integrity? Exists when every foreign key relates to an existing primary key. There are no orphan records in child tables that have no reference in a parent table.
PT2520
Unit 7 Labs
Lab 7.1
Lab 7.2
Lab 7.3
1. What does redundancy refer to? Redundancy refers to repeating the same data more than once; It occurs in a number of ways such as the data could be repeated over and over again in the same file.
2. What is a primary key? Each table usually has one column designated as a primary key . This key uniquely identifies each row in the table.
3. What is a foreign key? This primary key becomes a foreign key when it is repeated in another table to create a link between the tables.
4. What is SQL language? The programming language used to manipulate data and data objects in a relational database.
5. What are entities? An entity is something that the database is concerned with, about which data can be stored, and which can have relationships with other entities.
6. What are database requirements? This is something a database must do. For instance, it must keep track of tutors and the classes for which they can tutor.
7. What is data integrity? The accuracy and quality of the data.
8. What is a form? What is a report? A form is a document, paper or electronic, that is used to gather data. A report is a document, paper or electronic, used to display summarized or formatted data
9. What is the domain of a database? The focus of the database. If the database is about the tutoring program, its domain is “tutoring.”
10. What is work shadowing? Following and observing persons as they go through their work routine.
11. What are candidate keys? Attributes that could possibly be used as identifying attributes.
12. What is a composite key? A key that consists of more than one attribute.
13. What is referential integrity? Exists when every foreign key relates to an existing primary key. There are no orphan records in child tables that have no reference in a parent table.