Connecting Databases to Web Applications: A Comprehensive Guide for Web Developers

Question 1

When optimizing database queries for web applications, which technique should be prioritized first to improve query performance?

Accepted Answer

Query caching

Answer

Data denormalization

Answer

Table fragmentation

Answer

Ignoring indexing

Question 2

Which of the following is **NOT** a step involved in connecting a database to a web application?

Accepted Answer

Parsing the database response

Answer

Establishing a database connection

Answer

Executing queries

Answer

Retrieving data from the database

Question 3

Which programming language is **commonly used** for server-side web development and database interaction?

Accepted Answer

Python

Answer

HTML

Answer

CSS

Answer

JavaScript

Question 4

What is the **primary purpose** of a database connection pool?

Accepted Answer

To improve performance by reusing existing database connections

Answer

To limit the number of simultaneous database connections

Answer

To encrypt data during transmission

Answer

To manage database transactions

Question 5

Which of the following is a **widely used** database query language?

Accepted Answer

SQL

Answer

NoSQL

Answer

XML

Answer

JSON

Question 6

What is the **main role** of a database schema in web development?

Accepted Answer

To define the structure and relationships of data in the database

Answer

To store the actual data in the database

Answer

To manage user access to the database

Answer

To optimize database performance

Question 7

Which of the following is a **key benefit** of using an object-relational mapping (ORM) framework?

Accepted Answer

Simplifies database interaction by providing an object-oriented interface

Answer

Improves database performance by optimizing queries

Answer

Enhances data security by encrypting database connections

Answer

Reduces the need for database-specific knowledge

Question 8

What is the **primary reason** prepared statements are preferred over dynamic queries?

Accepted Answer

Prepared statements prevent SQL injection attacks, while dynamic queries do not

Answer

Dynamic queries are more efficient than prepared statements

Answer

Prepared statements are always preferable to dynamic queries

Answer

There is no significant difference between prepared statements and dynamic queries

Question 9

What is the **main purpose** of using a database transaction?

Accepted Answer

To ensure the atomicity, consistency, isolation, and durability (ACID) of database operations

Answer

To improve database performance by batching multiple queries

Answer

To prevent data loss in case of system failures

Answer

To manage user access to the database

Question 10

In the context of database-driven web applications, what is data integrity and why is it crucial?

Accepted Answer

Data integrity ensures data accuracy and consistency, preventing corruption and enhancing reliability.

Answer

Data integrity solely prevents unauthorized data access in web applications.

Answer

Data integrity is irrelevant in web applications due to constant data changes.

Answer

Data integrity is only essential for massive databases with millions of records.

Question 11

Which of the following is the primary server-side language used to connect databases to web applications?

Accepted Answer

PHP

Answer

JavaScript

Answer

CSS

Answer

HTML

Question 12

What is the primary purpose of a database connection object?

Accepted Answer

Establish and manage a connection to a database

Answer

Execute queries on the database

Answer

Validate user input

Answer

Store data retrieved from the database

Question 13

Which of the following syntax is valid for establishing a database connection using PHP?

Accepted Answer

$conn = mysqli_connect("localhost", "root", "password", "database_name");

Answer

$conn = mysql_connect("localhost", "root", "password", "database_name");

Question 14

What is the key difference between a SELECT statement and an INSERT statement in SQL?

Accepted Answer

SELECT retrieves existing data, while INSERT adds new data

Answer

They both perform the same function

Answer

SELECT adds new data, while INSERT retrieves existing data

Answer

SELECT updates data, while INSERT deletes data

Question 15

How do you retrieve data from a database using PHP?

Accepted Answer

Use the mysqli_query() function to execute a SELECT query and store the result in a result object

Answer

Use the PDO (PHP Data Objects) library to retrieve data

Answer

Use the mysql_fetch_array() function to directly access data from the database

Question 16

What is the primary role of a parameterised query in preventing SQL injection attacks?

Accepted Answer

It prevents malicious user input from being directly executed as part of the SQL statement

Answer

It encrypts user input before executing it

Answer

It validates user input against a predefined set of values

Question 17

Which of the following is a key advantage of using a web application framework for database connectivity?

Accepted Answer

Provides pre-built database connectivity components, reducing development time

Answer

Reduces the risk of security vulnerabilities

Answer

Improves the performance of database operations

Question 18

What is the primary difference between the mysqli_fetch_assoc() and mysqli_fetch_array() functions in PHP?

Accepted Answer

mysqli_fetch_assoc() returns an associative array, while mysqli_fetch_array() returns both a numeric and associative array

Answer

mysqli_fetch_assoc() returns a numeric array, while mysqli_fetch_array() returns an associative array

Question 19

What is the primary purpose of using a WHERE clause in a SQL statement?

Accepted Answer

To filter data based on specified conditions

Answer

To insert new data into a table

Answer

To sort data in a specific order

Answer

To group data into categories

Question 20

Which of the following is NOT a commonly used database connectivity method in web applications?

Accepted Answer

SOAP

Answer

ADO.NET

Answer

ORM

Answer

JDBC

Question 21

What is the primary purpose of using a connection pool in a web application?

Accepted Answer

To enhance performance and scalability by reusing existing database connections.

Answer

To secure database access by managing user credentials.

Answer

To simplify database query execution by providing pre-defined templates.

Question 22

Which of the following is a commonly used server-side scripting language for connecting to databases in web applications?

Accepted Answer

PHP

Answer

CSS

Answer

HTML

Answer

JavaScript

Question 23

What is a key advantage of using a data access object (DAO) in web development?

Accepted Answer

It promotes code reusability and simplifies database access logic.

Answer

It enhances database security by encrypting data.

Answer

It improves database performance by optimizing queries.

Question 24

What is the main purpose of implementing SQL injection prevention techniques in web applications?

Accepted Answer

To protect against malicious database attacks by filtering user input.

Answer

To ensure data integrity by validating user input.

Answer

To optimize database performance by caching query results.

Question 25

Which of the following is NOT a best practice for connecting databases to web applications?

Accepted Answer

Storing database credentials in plain text files.

Answer

Validating user input before executing database queries.

Answer

Using parameterized queries to prevent SQL injection.

Answer

Establishing secure database connections using SSL/TLS.

Question 26

What is the primary benefit of using an object-relational mapping (ORM) tool in web development?

Accepted Answer

It simplifies the interaction between objects and relational databases.

Answer

It enhances data security by encrypting database tables.

Answer

It improves database performance by optimizing queries.

Question 27

What is a key advantage of using a database transaction in a web application?

Accepted Answer

It ensures data integrity by ensuring that a series of database operations are either all completed successfully or all rolled back.

Answer

It improves database performance by reducing the number of database connections