CIS 2010 EXAM 3 Flashcards
What is an Entity in relational databases?
A table that stores multiple fields that describe something like an object or a place.
Define Attributes in the context of a database.
A field or column in a table that contains one characteristic of an entity.
What are Records in a relational database?
A collection of fields that describe a single instance of the entity.
What does Cardinality refer to in relational databases?
The type of relationships that are possible between entities (data tables).
True or False: Relational databases store all data in a single table.
False.
What is the purpose of separating entities into different tables?
To reduce redundant data.
What is Normalizing in the context of databases?
The process of separating entities and removing redundant data to as few copies as possible.
What is the consequence of redundant data in a database?
It creates a data quality challenge, as changes need to be made in every redundant copy.
What does SQL stand for?
Structured Query Language.
What is the main use of SQL?
To access and manipulate databases.
What are the two main logical sections of a basic SQL SELECT statement?
- What should we retrieve?
- From what database and table should we retrieve it?
What is the purpose of a WHERE clause in SQL?
To restrict the visible data based on a criteria.
Fill in the blank: In SQL, the command used to retrieve data is called _______.
SELECT.
What is a table in a relational database?
A structure that contains fields (attributes) organized into rows and columns.
What does each row in a student record table represent?
A new record for each instance of a student.
List three attributes that might be found in a student record.
- Student ID
- First Name
- Last Name
How is the table name specified in a SQL SELECT statement?
By providing the table name after the word FROM.
True or False: SQL commands are only used by programmers.
False.
