What is the purpose of a referential integrity constraint in a relational database?
To enforce relationships between tables by ensuring that related data exists
To prevent unauthorized access to sensitive data
To ensure that all data in a table is unique
To speed up data retrieval queries
Which of the following is NOT a characteristic of a table in First Normal Form (1NF)?
The table contains a foreign key referencing another table
A primary key uniquely identifies each row
Each column contains atomic values
There are no repeating groups of columns
Which statement is TRUE regarding the different normal forms?
1NF is the most desirable normal form for all databases
Normalization guarantees perfect database design
A table in 3NF is also automatically in 2NF and 1NF
2NF automatically implies 3NF
What SQL statement is used to add a new column to an existing table?
MODIFY TABLE
ADD COLUMN
ALTER TABLE
UPDATE TABLE
Which type of dependency does Third Normal Form (3NF) aim to eliminate?
Multi-valued dependency
Transitive dependency
Partial dependency
Join dependency
Which of the following is NOT a common SQL data type?
ARRAY
VARCHAR
BOOLEAN
INTEGER
Which data validation technique prevents invalid data from being entered into the database by checking it against predefined rules?
Data Masking
Check Constraints
Data Transformation
Data Scrubbing
In a normalized database, what is the typical relationship between tables?
Tables are completely independent
One table contains all the data, while others are empty
Tables are organized alphabetically
Tables are connected through foreign keys
A Foreign Key in a database is used to...
Define a new data type for a column.
Establish a link between two tables based on a common column.
Create a primary key for a related table.
Enforce data validation rules on a column.
What element in an ER diagram describes the properties or characteristics of an entity?
Cardinality
Entity
Attribute
Relationship