NoSQL

Question 1

What is NoSQL translated as?

Answer 1

Not Only SQL

Question 2

What is meant by “horizontally scalable”?

Answer 2

A horizontally scalable system is one that increase capacity by adding more computers.

Question 3

What is the main goal of NoSQL?

Answer 3

NoSQL is the answer to the need for more horizontally scalable systems.
* It is used when the three Vs arise

Question 4

What are the three V’s of Big Data?

Answer 4

Volume, variety and velocity.

Question 5

In the three V’s…

What does Volume mean?

Answer 5

A huge amount of data, sometimes data quality is compromised in order to cope.

Question 6

In the three V’s…

What is meant by Variety?

Answer 6

Data can arise in various, unpredictable formats.

Question 7

In the three V’s…

What is meant by Velocity?

Answer 7

Refers to the high speed of data flows. Speed is prioritised, so avoid storing data across multiple tables.

Question 8

What are ACID properties?

Answer 8

• A - Atomicity: The entire transaction happens all at once, or not at all.
• C - Consistency: The database must be consistent before and after the transation.
• I - Isolation: Multiple transactions occur independently without interference.
• D - Durability: The changes of a successful transaction occur even if the system failure occurs.

Question 9

What are the BASE model properties?

Answer 9

• BA - Basically Available: Distribute across storage systems through replication rather than a single large data store.
• S - Soft State: State changes over time with developers responsible for handling data consistency.
• E - Eventually Consistent: Consistency across several data servers at once.

Question 10

Where might the BASE model be used?

Answer 10

Social Media
* Loads of users generating data
* Stores a huge amount of data
* Can sort of be accessed offline, so it has a local cache.