12B revew midterms

What does ERD stand for in database design?

• Entity Relationship Data

• Entity Relationship Diagram

• Entity Reference Diagram

• Enhanced Relational Database

In an ERD, what do rectangles represent?

• Relationships

• Attributes

• Entities

• Primary Keys

What is the purpose of a primary key in a database table?

• To link tables together

• To allow duplicate values in a table

• To uniquely identify each record

• To store large amounts of text

Which SQL command is used to create a new table in SQLite?

• INSERT INTO

• CREATE TABLE

• NEW TABLE

• ADD TABLE

What type of relationship exists when one record in Table A relates to many records in Table B?

• One-to-One

• One-to-Many

• Many-to-Many

• None of the above

What is the SQL syntax to define a foreign key in SQLite?

• FOREIGN KEY (column_name) REFERENCES table_name(column_name)

• SET FOREIGN KEY (column_name) IN table_name(column_name)

• ADD FOREIGN KEY (column_name) TO table_name(column_name)

• LINK FOREIGN KEY (column_name) WITH table_name(column_name)

Which of the following best describes a one-to-one relationship?

• One student can enroll in multiple courses

• A country has multiple cities

• Each passport belongs to exactly one person

• A book can be borrowed by multiple students

In an ERD, what symbol is typically used to represent a many-to-many relationship?

• A solid line

• A crow’s foot

• A double circle

• A triangle

What happens if you try to insert a duplicate value into a primary key column?

• SQLite will allow it

• SQLite will generate a warning but insert the data

• SQLite will reject the insertion with an error

• SQLite will replace the existing record

What are the three main components of an ERD?

• Classes, Methods, Objects
• Tables, Columns, Rows
• Nodes, Edges, Weights
• Entities, Relationships, Attributes