CloudAcademy: Knowledge Check: Databases (SAA-C03) 1 of 2 Flashcards
Each of the following is a use case for Amazon ElastiCache except which choice?
A. improving read access performance
B. caches using secure, network-attached RAM
C. persistent data storage
D. in-memory data storage
C. persistent data storage
Explanation:
ElastiCache should never be used to store your only version of data records, since a cache is designed to be a temporary data store. So when data persistence is necessary, such as when we are working with primary data records, or when we need write performance rather than read performance, a persistent data store should be used instead of an ElastiCache.
When using Provisioned Capacity mode, how are you charged for Amazon DynamoDB?
A. by the total amount of storage space used by your data
B. by the amount of time your database is up and running
C. by the total amount of throughput that you configure for your tables plus the total amount of storage space used by your data
D. by the total amount of throughput that you configure for your tables
C. by the total amount of throughput that you configure for your tables plus the total amount of storage space used by your data
Explanation:
You are charged for the total amount of throughput that you configure for your tables plus the total amount of storage space used by your data.
How does the Amazon RDS multi-AZmodel work?
A. A second, standby database is deployed and maintained in a different availability zone from the master using asynchronous replication.
B. A second, standby database is deployed and maintained in a different region from the master using asynchronous replication.
C. A second, standby database is deployed and maintained in a different region from the master using synchronous replication.
D. A second, standby database is deployed and maintained in a different availability zone from the master, using synchronous replication.
A. A second, standby database is deployed and maintained in a different availability zone from the master using asynchronous replication.
Explanation:
In a Multi-AZ deployment, Amazon RDS automatically provisions and maintains a synchronous standby replica in a different Availability Zone.
Which Amazon RDS storage option does AWS provideonly to support backwardcompatibility?
A. General Purpose SSD
B. Provisioned IOPS (SSD)
C. Shared Cluster
D. Magnetic
D. Magnetic
Explanation:
Shared Cluster storage is available only for Amazon Aurora. General Purpose SSD is a good option for a wide range of use cases. Provisioned IOPS is ideal for workloads that require a high I/O. Magnetic storage is only recommended to supportbackward compatibility.
How does in-memory caching provided by ElastiCache improve the performance of applications?
A. It improves application performance by storing frequently-accesseddata in memory for low-latency access.
B. It improves application performance by deleting the requests that do not contain frequently accessed data.
C. It improves application performance by implementing good database indexing strategies.
D. It improves application performance by using a part of instance RAM for caching important data.
A. It improves application performance by storing frequently-accesseddata in memory for low-latency access.
Explanation:
In Amazon ElastiCache, in-memory caching improves application performance by storing critical pieces of data in memory for low-latency access. Cached information may include the results of I/O-intensive database queries or the results of computationally intensive calculations.
Which of the following statements about backups in Amazon RDS is true?
A. Neither manual nor automated backups are supported.
B. Only manual backups are supported.
C. Only automated backups are supported.
D. Both manual and automated backups are supported.
D. Both manual and automated backups are supported.
Explanation:
From a backup perspective, by default, Amazon RDS provides an automatic feature. You can also perform manual backups, which are known as snapshots, any time you need to.
An in-memory cache is generally used to improve _____.
A. both read and write performance
B. read-only performance
C. write-only performance
D. the space efficiency of your database
B. read-only performance
Explanation:
A common scenario is to have a web application that reads and writes data to persistent storage–for example, to a relational database such as RDS or a NoSQL database such as DynamoDB. This is where an in-memory cache is useful. It’s generally used to improve read-only performance.
Which of the following statements about read replicas in Amazon RDS is false?
A. Read replicas help to alleviate the bottleneck on your primary database.
B. A read replica allows its users to read and write data.
C. If at any time your primary database goes down, you have the ability to promote a read replica into a new primary database.
D. A read replica is kept in sync with the primary database.
B. A read replica allows its users to read and write data.
Explanation:
A read replica is a copy of your database that gives the user another access point to retrieve data from. This helps to alleviate the bottleneck on your primary database. The read replica is kept in sync with the primary database and only allows its users to read data. If at any time your primary database happens to go down or become corrupted in some fashion, you have the ability to promote your read replica into a new primary database. Your traffic can migrate over to this copy using Route 53 failover routing and health checks.
Which Amazon RDS DB engine uses the BYOL DB instance purchase option?
A. MariaDB
B. PostgreSQL
C. SQL Server
D. Oracle
D. Oracle
Explanation:
The different payment options within RDS include on-demand instances, on-demand instances (BYOL), reserved instances, reserved instances (BYOL), and serverless.
Currently, only the Oracle database engine uses the BYOL purchase options, all other DB engines only use on-demand instances and reserved instances, with the added exception of Aurora also using serverless as an additional purchasing option.
Which of the following is not a typical use case for Neptune graph databases?
A. online games
B. fraud detection
C. social networking
D. recommendation engines
A. online games
Explanation:
Before I continue, let me run through some of the use cases to help you understand when and where you might use Amazon Neptune as a graph database to solidify the importance of being able to query complex relationships. Graph databases are a powerful asset when used within a social networking environment. Fraud detection: Security should always be a number-one priority in any cloud deployment solution, and using Amazon Neptune can help you from a security standpoint, using its high performance capabilities. Recommendation engines are widely used across many different websites, largely eCommerce sites that recommend products based upon your search and purchase histories.
What is an endpoint on Amazon Neptune?
A. A virtual database cluster volume that contains the data across all instances within the cluster
B. A fixed-sized chunk of secure, network-attached RAM
C. A URL address and a port that points to your components
D. A replica instance that scales read-only operations
C. A URL address and a port that points to your components
Explanation:
An endpoint is simply a URL address and a port that points to your components.
What is an Elasticache cache node?
A. a group of at least90 Redis shards
B. a parameter group that contains configurational settings about your engine
C. a fixed-sized chunk of secure, network-attached RAM
D. a group of at least 60 Memcached shards
C. a fixed-sized chunk of secure, network-attached RAM
Explanation:
A cache node is a fixed-sized chunk of secure, network-attached RAM, essentially the building block of the ElastiCache service, and supports a clustered configuration.
Which of the following is a type of Amazon Neptune endpoint?
A. A cluster
B. An instance
C. All of these are Neptune endpoints.
D. A reader
C. All of these are Neptune endpoints.
Explanation:
There are three different types of Amazon Neptune endpoints: cluster endpoint, reader endpoint, and instance endpoint.
Amazon ElastiCache allows you to retrieve information from _____.
A. different web servers in the cloud
B. NoSQL databases
C. relational databases
D. in-memory data stores
D. in-memory data stores
Explanation:
Amazon ElastiCache is a service that makes it easy to deploy, operate, and scale open-source, in-memory data stores in the cloud. This service improves performance through caching, where web applications allow you to retrieve information from fast, managed, in-memory data stores instead of relying entirely on slower disk-based solutions.
When managing your RDS DB instances, what are two important aspects of database engine upgrades you should always keep in mind? (Choose 2 answers)
A. Storage capacity
B. whether the upgrade is major or minor
C. backward compatibility
D. Instance licensing requirements
C. backward compatibility
B. whether the upgrade is major or minor
Explanation:
The first thing to consider is whether a DB engine upgrade is a major or minor update. This will indicate the extent of changes to the database. One way to determine this is to review the DB engine version numbers. For example, for a MySQL DB instance in Amazon RDS, version numbers like X.Y.Z are organized as follows:
MySQL version = X.Y.Z
X = Major version
Y = Release level
Z = Version number within release series.
If a release is minor, it is more likely your application need little to no testing before being released an updated instance. If a release is major, AWS recommends testing your application on the new DB engine version before deploying it in a production environment or updating any existing DB instances to the version. This is especially important because while minor updates are usually backward compatible, major updates often include changes that are not.
