Question $1$

Which of the following is true about a VARCHAR?

$1$ point

The denotation of its maximum length is in brackets after the type name, such as VARCHAR $(10).$

It is a string of variable length.

It has a fixed length.

It uses the same amount of space in the database irrespective of the length of the actual data stored in it$.$

$2.$

Question $2$

The surge in popularity of cloud databases over the past decade results from which cloud service model?

$1$ point

Platform as a Service $($PaaS$)$

Infrastructure as a Service $($IaaS$)$

Commercial databases

Software$-$as$-$a$-$Service $($SaaS$)$

$3.$

Question $3$

In a $2-$tier environment, the server$$s DBMS comprises various layers. Which of these layers is commonly known as the persistence layer?

$1$ point

Database Engine layer

Transmission layer

Database Storage layer

Data Access layer

$4.$

Question $4$

Which NoSQL functionality does PostgreSQL use to store non$-$hierarchical data?

$1$ point

JSON

Replication

Functions

HSTORE

$5.$

Question $5$

What is the purpose of the Entity Relationship Diagram $($ERD$)$ model?

$1$ point

The ERD model helps you map data types to existing columns and rows.

The ERD model helps you to define entities and their attributes, map them to tables, and identify the relationships between the tables.

The ERD model helps you define the data in each table row.

The ERD model helps you to design a database with a single table.

$6.$

Question $6$

Which data source is NOT compatible with the Db$2$ Web Console for data loading?

$1$ point

S$3$ object storage $($AWS$)$

Python code

Cloud Object Storage $($IBM$)$

Delimited text files $($local computer$)$

$7.$

Question $7$

When creating a foreign key, how can you define an action to take if a parent table row is updated?

$1$ point

Use the rule clause

Use the CREATE TABLE command

Use the ON DELETE CASCADE clause

Use the ALTER TABLE command

$8.$

Question $8$

In the given options, the situation best suited for indexing is:

$1$ point

When the database contains unstructured data

When you need to delete the data

With a table that often has rows inserted or updated

When a table is regularly accessed using a SELECT statement, but rows insert$/$update$/$delete scenarios are rare.

$9.$

Question $9$

Which constraint specifies the permissible values for a given attribute?

$1$ point

Unique constraint

Domain constraint

Semantic integrity constraint

Entity integrity constraint

$10.$

Question $10$

What is the difference between system schemas and user schemas?

$1$ point

System schemas store configuration information and metadata

Neither schema contains database objects

System schemas contain partitions, and user schemas contain metadata

Both schemas contain the same objects

$11.$

Question $11$

What statement best describes phpMyAdmin?

$1$ point

It is an admin tool that manages users and their access permissions

It is a cloud$-$based tool used to access MySQL

It is a graphical user interface $($GUI$)$ to interact with MySQL

It is a command$-$line interface

$12.$

Question $12$

Which command do you use to show the structure of a table?

$1$ point

DESCRIBE

SHOW

REPRESENT

DISPLAY

$13.$

Question $13$

What does the $-$u root$$ option in this command do$?$

mysqldump $-$u root employees $>$ employeebackup.sql

$1$ point

Uses the root directory to back up the database on the server

Lists users who have access to the root directory

Uses the root directory to find the database file that is to be backed up

Specifies the username $$root$$ when connecting to the server

$14.$

Question $14$

What open$-$source graphical user interface $($GUI$)$ can you utilize to connect to a Postgres database?

$1$ point

pgAdmin

Navicat

phpAdmin

PostgreSQL

$15.$

Question $15$

Why are views useful?

$1$ point

They help determine information system requirements throughout an organization

They limit access to sensitive data

They help identify data you want to work with

They make it easier to join data in tables