SQL Knowledge Quiz2

Which of the following is NOT a type of SQL statement?

• Data Definition Language (DDL)

• Data Manipulation Language (DML)

• Data Transaction Language (DTL)

• Data Control Language (DCL)

Why are SQL constraints used?

• To improve database performance

• To enforce data integrity rules

• To speed up data retrieval

• To define indexes on columns

Which of the following is NOT a constraint in SQL?

• PRIMARY KEY

• FOREIGN KEY

• NOT NULL

• UNIQUE INDEX

Which of the following is NOT an aggregate function in SQL?

• COUNT

• SUM

• AVG

• SELECT

What is an Index in SQL?

• A method of limiting access to sensitive data

• A performance optimization tool for faster data retrieval

• A constraint for ensuring data integrity

• A way to store data in multiple tables

Which of the following is NOT a type of index in SQL?

• Clustered Index

• Non-clustered Index

• Unique Index

• Referential Index

What is SQL Injection?

• A type of performance issue in SQL queries

• A method of injecting additional rows into a table

• A security vulnerability allowing attackers to manipulate SQL queries

• A technique for optimizing SQL queries

Which of the following is a key difference between a "Primary Key" and a "Unique Key"?

• A Primary Key can have NULL values, whereas a Unique Key cannot.

• A Primary Key uniquely identifies each record in a table, whereas a Unique Key allows one NULL value.

• A Primary Key is optional, whereas a Unique Key is mandatory.

• There is no difference between them.

What is a Cursor in SQL?

• A method for filtering data in SELECT queries

• A pointer that allows iteration over a set of rows

• A function to join tables

• A type of index used to optimize query performance

How can you change the database name in SQL Server?

• By using the `ALTER DATABASE` statement

• By renaming the file directly on the disk

• By using `UPDATE DATABASE` statement

• It is not possible to change the database name in SQL Server