MySQL

• Which of the following is described graphically using an E-R diagram?

Làm lại

• Data flows between processes

• Data source and destination

• Entities and relationships between entities

• Hierarchical data structure

• SQL query and modification commands make up a(n)

• XML

• DML

• HTML

• DDL

• A/an _________ is a piece of information that in some way describes an entity. It is a property of the entity and it quantifies, qualifies, classifies or specifies the entity.

• Table

• Process

• ERD

• Attribute

• What is the purpose of a Unique Constraint?

• To uniquely determine a table and columns within that table.

• To identify a specific row within a table, using one or more columns and/or foreign keys.

• Create an entity that is unlike any other entity aside from itself.

• To identify one unique instance of an entity, by using one or more attributes and/or relationships.

• Which of the following entities most likely contains invalid attributes?

• Entity: Home. Attributes: Number of Bedrooms, Owner, Address, Date Built

• Entity: Mother. Attributes: Name, Birthdate, Occupation, Salary

• Entity: Car. Attributes: Owner Occupation, Owner Salary, Speed

• Entity: Pet. Attributes: Name, Birthdate, Owner

• In a 1:N relationship, the foreign key is placed in:

• either table without specifying parent and child tables

• the parent table

• the child table

• either the parent table or the child table

• You are building a new database for a company with 10 departments. Each department contains multiple employees. In addition, each employee might work for several departments. How should you logically model the relationship between the department entity? 

• Create a mandatory one-to-many relationship between department and employee.

• Create an optional one-to-many relationship between department and employee.

• Create a new entry, create a one-to-many relationship from the employee to the new entry, and create a one-to-many relationship from the department entry to the new entry.

• Create a new entry, create a one-to-many relationship from the new entry to the employee entry, and then create a one-to-many relationship from the entry to the department entry.

• In a 1:1 relationship, the foreign key is placed in:

• either table without specifying parent and child tables

• the child table

• either the parent table or the child table

• the parent table

• In which of the following can many entity instances of one type be related to many entity instances of another type?

• One-to-One Relationship

• Many-to-Many Relationship

• One-to-Many Relationship

• Composite Relationship

• What data type is “Distance from home to school ”should be?

• Decimal

• Text

• Bigint

• Int