Databases Flashcards
1
Q
In a relational database, what language is used to perform queries or lookups?
A
SQL
2
Q
What type of database does NoSQL reflect?
A
Non relational database
3
Q
In regards to database, what is meant by “schema”?
A
Basically, the shape of the data
4
Q
What type of database offers a flexible schema?
A
non relational
5
Q
The following are examples of what type of database?
Key-value, document, graph, in-memory, search databases
A
non relational
6
Q
the following is an example of what type of database?
flexible (easy to evolve data model)
scalable - designed to scale out by using distributed clusters
high-performance - optimized for a specific data model
highly-functional - optimized for the data model
A
non relational
7
Q
what does JSON stand for?
A
java script object notation
8
Q
In the Shared Responsibility model, who is responsible for patching OS and database patching?
A
AWS
9
Q
In the Shared Responsibility model, who is responsible for automated backup and restore, operations, and upgrades?
A
AWS
10
Q
In the Shared Responsibility model, who is responsible for monitoring and alerts?
A
AWS
11
Q
For RDS services, how is the storage managed?
A
EBS (gp2 or ioL)
12
Q
Can you SSH into an RDS instance?
A
No
13
Q
What are the two services you can utilize to create relational databases in AWS?
A
RDS or Aurora
14
Q
This type of database is OLAP (analytics & data warehousing)
A
Redshift
15
Q
What type of database is based on PostgreSQL but doesn’t use OLTP
A
Redshift
16
Q
How often does Redshift load data?
A
every hour
17
Q
Is RDS a single or multi-AZ service, and why?
A
multi-AZ, for data reliability (disaster recovery)
18
Q
What type of replicas are provided for RDS, “read/write” or “read”?
A
read
19
Q
what two types of query languages are supported by Amazon Aurora?
A
PostgreSQL and and MySQL
20
Q
Aurora is ____ optimized
A
cloud
21
Q
Aurora claims _x performance in PostgreSQL over RDS and _x performance in MySQL over RDS
A
3x and 5x
22
Q
Aurora storage is adjusted
a. automatically
b. manually
A
a. automatically
23
Q
Aurora storage is automatically incremented by __ GB up to a maximum of __ TB
A
10GB, 128TB
24
Q
Which is more expensive, Aurora or Amazon RDS?
A
Aurora
25
How much more expensive is Aurora over Amazon RDS?
20%
26
Aurora storage (Is/Is Not) in the free tier?
Is not
27
Amazon RDS can have a maximum of how many "read" replicas?
5
28
With Amazon RDS, data is only written to where?
the main DB
29
Amazon RDS, how many AZs can be utilized as a fail-over?
1
30
Which type of managed relational database is going to be more cloud native? which one will work more with the technologies you're probably already familiar with?
Aurora / RDS
31
When starting a new database from the RDS service, which database options are available to choose from?
PostgreSQL (Aurora)
PostgreSQL
MySQL (Aurora)
MySQL
MariaDB
Oracle
SQL Server
32
In a failover DB (multi-AZ) where is the data written to and read from?
the main DB only
33
The failover database is considered to be (passive/active)?
passive
34
When is the failover DB accessible?
only after a failure to the main DB
35
If you want to copy your database to another region, what is a method you can use?
Create a snapshot into another region
36
What would be two reasons to setup a multi-region DB deployment, where data is written to and read from one main DB but replicas are created in other regions?
one - disaster recovery if there's an issue with a given region
less latency - the application is reading data from a "read replica" that's in a region closer to where the application is located
37
Anytime you hear "in-memory databases with high performance and low latency" what should you think of?
ElastiCache
38
This is an example of what "helps reduce load off databases for read intensive workloads"
ElastiCache
39
DynamoDB replicates across how many AZs?
three
40
What type of database is this referring to:
"scales to massive workloads, distributed "serverless" database, millions of requests per seconds, trillions of rows, 100s of TB storage, single digit millisecond latency, low latency retrieval
Dynamo DB
41
If the certification exam refers to "single digit millisecond latency" and/or "low latency retrieval" - what type of database is it likely referring to?
Dynamo DB
42
True or False:
Dynamo DB has low cost and auto scaling capabilities?
True
43
What type of S3 storage class is offered by Dynamo DB?
standard and IA
44
the name for a fully managed, in-memory cache for DynamoDB
DynamoDB Accelerator - DAX
45
DynamoDB Accelerator DAX offers a __x performance improvement
10x
46
Theoretically, can ElastiCache be used as an in-memory DB for DynamoDB?
It could, but it's recommended to use Dynamo Accelerator DAX instead as that is formulated for use with Dynamo
47
DynamoDB replication is an (active/passive) replication?
active
48
DynamoDB region replication is referring to as G_____ T_____.
global tables
49
With DynamoDB replication, read/writes are performed on which databases?
all
50
Redshift is used with what type of inquiry programming?
PostgreSQL
51
If an exam question refers to "warehouse" and "data analytics" and/or columnar data storage, you would think of this type of database.
Redshift
52
Redshift store data in a (columnar/row) format
columnar
53
Redshift payment is:
- Pay per column of data
- Reserve storage for 1 or 3 years
- Pay as you go
- paid with a valpak coupon
pay as you go
54
This type of database has Massively Parallel Query Execution (MPP) and is highly available
Redshift
55
Redshift uses a S__ interface to perform the queries
SQL
56
This database is integrated with BI (Business Intelligence) tools such as AWS Quicksight or Tableau
Redshift
57
AWS Quicksight or Tableau are considered B_______ I___________ tools
Business Intelligence
58
Amazon EMR stands for El___ Ma_ Red___
Elastic Map Reduce
59
What database is utilized in creation of Hadoop clusters (big data) to analyze and process vast amounts of data
Amazon EMR (Elastic Map Reduce)
60
Amazon EMR (Elastic MapReduce) is utilized to create Ha_o__ clusters
hadoop
61
what type of cluster is used to analyze and process vast amounts of data?
hadoop cluster
62
hadoop is an op__ so__ technology
open source
63
When using EMR, you can make a cluster of how many EC2 instances?
hundreds
64
EMR also supports Apa___ Sp_r_, HBase, Presto, and Flink
Apache Spark
65
Amazon EMR has auto_s______ and integrated with S___ instances
auto scaling, spot instances
66
use cases for EMR include d___ p____, m___ l____, w___ i___, big data
data processing, machine learning, web indexing, big data
67
From an exam perspective, anytime you see "hadoop cluster" the answer should be ...
EMR
68
a serverless query service to perform analytics against S3 objects
Athena
69
what type of query language is used by Athena
SQL
70
The pricing for Athena is about $_ per _B of data scanned
$5 for TB of data scanned
71
from exam perspective, if you see "analyze data in S3 using serverless SQL" .. what type of database service should you think of?
Athena
72
In Athena, use com___ or col___ data for cost-savings
compressed or columnar
73
this service creates interactive dashboards
QuickSight
74
If you want to create dashboards based on your databases to help customers visualize the data, what service should be utilized?
QuickSight
75
D_DB is an AWS-implementation of MongoDB similar to how Aurora is an AWS implementation of PostgreSQL and MySQL
DocumentDB
76
M_DB is used to store, query, and index JSON data
MongoDB
77
MongoDB is used to store, query and index what kind of data?
JSON data
78
DocumentsDB is replicated across _ AZs
three
79
Document DB storage grows in increments of __GB up to a maximum of __TB
10 GB, 64 TB
80
DocumentDB can scale to m____s of workloads per second
millions
81
This database resonates with a planet and God of the Sea is a graph database service
Neptune
82
A so____ ne___ is an example of a graph dataset.
a social network
83
Neptune has replication across _ AZs and can have up to __ read replicas
3, 15
84
from an exam perspective, when you see "graph dataset" think ....
Neptune
85
What does Amazon QLDB stand for?
Quantum Ledger Database
86
Amazon QLDB is a ledger of f___ transactions
financial
87
Amazon QLDB has replication across _ AZs
3
88
This service is used to review history of all the changes made to your application data over time?
QLDB (quantum ledger database)
89
QLDB is a (mutable/immutable) system for which entries (can/cannot) be modified (useful for financial ledgers).
immutable / cannot
90
QLDB provides _x-_x better performance than common ledge blockchain frameworks
2 - 3
91
QLDB can manipulate data using S___
SQL
92
____ has a central authority component whereas Amazon M____ B____ has no decentralized component
QLDB, Amazon Managed Blockchain
93
Anytime you see "financial transactions" and "ledger" think....
QLDB
94
Managed Blockchain is considered to be (centralized/decentralized)
decentralized
95
_____ makes it possible to build applications where multiple parties can execute transactions without the need for a trusted, central authority
Managed Blockchain
96
from an exam perspective, if you see anything related to blockchains, Hyperledger Fabric or Ethereum, think ...
Amazon Managed Blockchain
97
Managed extract, transform, and load (ETL) service
AWS Glue
98
what does ETL stand for (ex_, tra_, and l__d)
extract, transform, and load
99
How do you migrate data from one database to another?
Database migration service
100
When running the AWS Data Migration, the source database (is temporarily unavailable/remains available)
remains available
101
what is a homogeneous migration?
when the source and target DB are both the same type of DB (ie Oracle to Oracle)
102
what is a heterogeneous migration?
when the source and target DB are both different (ie SQL Server to Aurora)
103
What database?
Warehouse
OLAP (onilne analytic processing) / Redshift (SQL)
104
What database?
In memory
ElastiCache
105
What kind of database?
Key/Value database?
Dynamo and, for cache of Dynamo Accelerator DAX
106
What kind of database?
hadoop cluster
EMR
107
What kind of database?
query data on Amazon S3 (serverless & SQL)
Athena
108
What kind of database?
Serverless, Dashboards on your data
QuickSight
109
What kind of database?
"Aurora for MondoDB" (JSON - NoSQL database)
DocumentDB
110
What kind of database?
Financial ledger
Immutable journal
cryptographically verifiable
Amazon QLDB (Quantum Ledger database)
111
What kind of database?
managed Hyperledger Fabric
Etherneum
blockchains
Amazon Managed BlockChain
112
What kind of database?
Managed ETL (extract, transform, load)
catalog services
Glue Managed ETL
113
What kind of database?
migration
Data Migration Service
114
What kind of database?
graph
Neptune
115
Dynamo utilized what type of query language?
NoSQL
116
What is the the main purpose for RDS "read replicas"
scalability
117
What is the main purpose for multi-AZ deployments?
high availability
118
What is covered under the free tier for RDS? Dynamo?
RDS - 750 hours of usage / month
Dynamo - 25GB storage (S3 standard or IA) / usage is not free
119
Amazon RDS - how many instance classes are there?
three
120
Amazon RDS - which are actual instance classes to choose from (select three):
Standard
Memory Optimized
Compute
Database Max
Burstable performance
Standard
Memory Optimized
Burstable performance
121
1 - Eventually Consistent Reads
2 - Strongly Consistent Reads
A - When you read data from a DynamoDB table, the response might not reflect the results of a recently completed write operation. The response might include some stale data. If you repeat your read request after a short time, the response should return the latest data.
B - DynamoDB returns a response with the most up-to-date data, reflecting the updates from all prior write operations that were successful. However, this consistency comes with some disadvantages:
1A
2B
