Databases Flashcards
SQL Server, Oracle, MySQL, PostgreSQL, MariaDB and Amazon Aurora are examples of what database type?
RDS (Relational Database Service)
______ databases are best for OLTP (Online Transition Processing) Workloads like processing lots of small transactions like customer orders, banking transactions, payments, and bookkeeping systems.
RDS (Relational Database Service)
True or False. RDS is most suitable for OLAP (Online Analysis Processing).
False.
______ is most suitable for OLAP tasks, like analyzing large amounts of data, reporting and sales forecasting.
Redshift
True or False. Read replicas are primarily used for scaling, and disaster recovery.
Read Replicas are not suitable for disaster recovery
________ a read-only copy of your primary database in the same availability zone, cross-AS or cross-region that is used to increase or scale read performance.
Read Replicas
______ is an exact copy of your production database in another availability zone and is only used for disaster recovery.
RDS Multi-AZ
If you can’t, for some reason, create a read replica of your primary database, what is a likely cause?
You haven’t turned on automatic backups.
Amazon’s proprietary database.
It’s compatible with MySQL as well as PostgreSQL.
Aurora
_________ provides a relatively simple, cost-effective serverless database option for infrequent, intermittent, or unpredictable workloads.
Aurora Serverless
Aurora maintains ____ copies of your data in each Availability zone, with a minimum of 3 availability zones: so _____ copies of your data.
2, 3, 6
True or false? You can share Aurora snapshots with other AWS accounts.
True
3 types of replicas available with Aurora
Aurora Replicas, MySQL Replicas, PostgreSQL replicas.
True or False. Automated failover is only available with Aurora replicas.
True
Dynamo DB is stored on what type of storage?
SSD
DynamoDB is spread across how may geographically distinct data centers?
3
___________ reads means that consistency across all copies of data within DynamoDB is usually reached within about a second, and repeating a read after a short time should return the updated data. And this gives you the best read performance.
Eventually consistent
If your application needs to automatically get
any changes to the data within DynamoDB, you want to turn on ___________ reads. This will return a result that reflects all writes that have received a successful response prior to the read.
strongly consistent
____________ provides developers
with atomicity, consistency, isolation, and durability (ACID) across one or more tables within a AWS account or AWS region.
DynamoDB transactions
If you see something about ACID requirements
with DynamoDB, you need to use DynamoDB transactions. This is basically means
you’ve got all-or-nothing transactions. So you either need to add an item to all the tables in one transaction, but if one of those tables fails for whatever reason, you don’t want one item going into one table, not into another table,
because that wouldn’t have ACID consistency.
So you need to make sure you’ve got DynamoDB transactions turned on, and that way, either the write will happen or it won’t.
True or False? DynamoDB On-Demand Backup and Restore provides full backups at any time; backups older than 360 days are deleted by default.
False. DynamoDB On-Demand Backup and Restore provides
- full backups at any time consistent within seconds and retained until deleted.
True or False. DynamoDB On-Demand Backup and Restore operates within the same region as the source table.
True
Select the features that correct describe DynamoDB Point-in-Time Recovery (PITR)
a. Protects against accident writes or deletes
b. Restore to any point in the last 60 days
c. Differential Backups
d. Not enabled by default
e. Latest restorable: 5 minutes in the past
a. Correct
b. Incorrect. Correct answer is restore to any point in the last 35 days.
c. Incorrect. Correct answer is incremental Backups
d. Correct
e. Correct
DynamoDB _______ allows you to maintain First-In-First-Out records of your data. So as you go and add transactions, basically it’s given a sequence number. These sequences are stored in a stream, and the data’s broken up into shards. So it’s just time-ordered sequences of item-level changes in a table.
DynamoDB streams.
As you go and add transactions, basically it’s given a sequence number. These sequences are stored in a stream, and the data’s broken up into shards. So it’s just time-ordered sequences of item-level changes in a table.
DynamoDB _______ allows you to maintain First-In-First-Out records of your data. So as you go and add transactions, basically it’s given a sequence number. These sequences are stored in a stream, and the data’s broken up into shards. So it’s just time-ordered sequences of item-level changes in a table.
DynamoDB streams.
As you go and add transactions, basically it’s given a sequence number. These sequences are stored in a stream, and the data’s broken up into shards. So it’s just time-ordered sequences of item-level changes in a table.
