Why database choice impacts architecture in HLD - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to select the type of database based on data structure.

HLD

if data_is_structured:
    database_type = '[1]'
else:
    database_type = 'NoSQL'

Drag options to blanks, or click blank then click option'

AKey-Value

BGraph

CRelational

DDocument

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing NoSQL for structured data

Confusing document and relational databases

Structured data is best handled by relational databases because they organize data in tables with fixed schemas.

2fill in blank

medium

Complete the code to choose a database type that supports flexible schema.

HLD

if need_flexible_schema:
    database_type = '[1]'
else:
    database_type = 'Relational'

Drag options to blanks, or click blank then click option'

ARelational

BNoSQL

CGraph

DTime-Series

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing relational databases for flexible schema

Confusing graph and time-series databases

NoSQL databases allow flexible schemas, making them suitable for evolving or unstructured data.

3fill in blank

hard

Fix the error in the code that selects database based on query type.

HLD

if query_type == 'relationship-heavy':
    database = '[1]'
else:
    database = 'Relational'

Drag options to blanks, or click blank then click option'

AGraph

BNoSQL

CKey-Value

DDocument

Attempts:

3 left

💡 Hint

Common Mistakes

Using relational databases for relationship-heavy queries

Choosing key-value stores incorrectly

Graph databases are optimized for queries involving complex relationships between data.

4fill in blank

hard

Fill both blanks to complete the code that estimates database impact on system design.

HLD

if database_type == '[1]':
    scaling_strategy = '[2]'
else:
    scaling_strategy = 'Vertical Scaling'

Drag options to blanks, or click blank then click option'

ANoSQL

BHorizontal Scaling

CRelational

DSharding

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing relational for horizontal scaling

Confusing sharding with scaling strategy

NoSQL databases often use horizontal scaling to handle large volumes of data by adding more servers.

5fill in blank

hard

Fill all three blanks to complete the code that decides consistency model based on database type.

HLD

if database_type == '[1]':
    consistency = '[2]'
else:
    consistency = '[3]'

Drag options to blanks, or click blank then click option'

ARelational

BStrong Consistency

CEventual Consistency

DNoSQL

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up consistency models

Assigning eventual consistency to relational databases

Relational databases usually provide strong consistency, while many NoSQL databases offer eventual consistency for better availability.