Interview Questions.

Question 1. Explain What Is Dynamodb?

Answer :

It is a NoSQL database carrier that's superintendent and affords rapid and inevitable performance with seamless scalability.
It also enables the users to dump the operating and scaling disbursed databases to AWS.
So that the customers don’t ought to worry about setup and configuration, hardware provisions, replication, throughput potential making plans, cluster scaling or software patching.
Question 2. List Some Benefits Of Using Amazon Dynamodb?

Answer :

Here is the listing of some of the benefits of the usage of Amazon DynamoDB:

It is a managed service where there is no need to lease the experts or worry about set up, setup, cluster and so forth.,
It is scalable.
It presents the customers excessive throughput at very low latency.
It is durable and pretty available.
It is flexible and permits dynamic tables advent that consists of multi-valued attributes.
It is cost-effective.
RDBMS Interview Questions
Question 3. What Are The Non-relational Databases?

Answer :

The Non-Relational databases are NoSQL databases.

These databases are labeled into 4 businesses. 

They are:

Key-fee shops
Graph shops
Column shops
Document shops 
Question four. Is Dynamodb Free For Use?

Answer :

In Amazon DynamoDB you only pay for the resources you provision.
Get started out with free tier limits of DynamoDB on which many packages perform.
In want of sources, the pricing consistent with month varies depending on ?which sort of resources you require.
MySQL Tutorial
Question five. Explain What Is Dynamodb Mapper Class?

Answer :

It is the access point to DynamoDB.The DynamoDB Mapper magnificence gives access to a DynamoDB endpoint and allows the user to get entry to to their records in diverse tables, execute queries and test towards tables, and carry out CRUD operations on items.

Oracle Interview Questions
Question 6. List The Data Types Supported By Dynamodb?

Answer :

DynamoDB supports four scalar statistics sorts, and they may be:

Number
String
Binary
Boolean
 DynamoDB supports collection records sorts consisting of:

Number Set
String Set
Binary Set
Heterogeneous List
Heterogeneous Map
DynamoDB also supports Null values.

Question 7. Does Dynamodb Support In-place Atomic Updates?

Answer :

Amazon DynamoDB supports brief in-location atomic updates, had been the numeric attributes increment and decrement can be completed in arrow the usage of just one API name or further, you can add or cast off units, lists, or maps.

CouchDB Tutorial MySQL Interview Questions
Question eight. What Kind Of Query Functionality Does Dynamodb Support?

Answer :

It supports GET/PUT operation the use of the user-described primary key.
It provides bendy querying by means of letting query a non-primary key characteristic the use of neighborhood secondary indexes and Global secondary indexes.
It permits quick reads and writes records for an object related to unmarried attribute partition number one key.
It permits you to use the Query API to retrieve all of the gadgets for a single composite partition-kind key throughout a number kind keys.
Question nine. Does Amazon Dynamodb Support Conditional Operations?

Answer :

For an operation to be finished on an object, you have to specify a condition.You can define a ConditionExpression that can be constituted of the following:

Boolean features:

ATTRIBUTE_EXIST, CONTAINS, and BEGINS_WITH

Comparison operators:

=, <>, <, >, <=, >=, BETWEEN, and IN
Logical operators:

NOT, AND, and OR.            

You can also assemble a free-shape conditional expression that combines multiple conditional clauses which additionally consists of nested clauses.

Amazon Web Services (AWS) Interview Questions
Question 10. List Some Difference Between Amazon Dynamodb And Amazon Simpledb?

Answer :

Amazon DynamoDB :

It is a fast and scalable NoSQL Database Service this is designed for internet scale applications, to maintain predictably excessive overall performance and to be quite fee-powerful for workloads of any scale, at the pinnacle of all it is particularly recommended.

Amazon SimpleDB :

It has scaling barriers and is a great in shape for smaller workloads that calls for question flexibility.It automatically indexes all object attributes and supports question flexibility on the cost of overall performance and scale.

Question 11. List The Apis Provided By Amazon Dynamodb?

Answer :

UpdateTable
DeleteTable
DescribeTable
ListTables            
PutItem
BatchWriteItem
UpdateItem
DeleteItem
GetItem
BatchGetItem.
Query
Scan
NoSQL Interview Questions
Question 12. What Amazon Dynamodb Batchwriteitem Api Does?

Answer :

The Amazon DynamoDB BatchWriteItem inserts, deletes and replaces a couple of gadgets throughout a couple of tables in just one request, however now not in a single transaction.
With maximum general request length of sixteen MB, it helps batches of up to twenty-five items to insert or delete.
RDBMS Interview Questions
Question thirteen. Explain Key-fee Store?

Answer :

It is a database service that offers and helps storing, updating and querying the gadgets which can be recognized using key and values that constitutes the real content material this is being saved.

Question 14. What Is Dynamodb Auto Scaling?

Answer :

DynamoDB is a superintendent feature that scales up and down the read and write potential of a DynamoDB or a global secondary index automatically.

Question 15. What Are Global Secondary Indexes?

Answer :

An index with a unique partition and partition-and-kind key from those at the table is known as international Secondary index.
It is taken into consideration to be “worldwide” in the experience that queries on the index can span all of the objects in a table across, all the walls.
CouchDB Interview Questions
Question 16. List Types Of Secondary Indexes Supported By Amazons Dynamodb?

Answer :

Two types of indexes are supported by Amazon DynamoDB.

They are:

Global Secondary index :

It is an index with a partition or a partition type key this is specific from those at the table. The international secondary index is considered to be international due to the fact queries on the index can span all the items in a table, throughout all of the partitions.

Local secondary index :

An index that has the same partition key as that of the table however specific sort key. It is considered to be “local” due to the fact every partition of the index is scoped to a desk partition that has the identical partition key.

Question 17. How Many Numbers Of Global Secondary Indexes Do You Create Per Table?

Answer :

You are allowed to create a maximum of 5 international secondary indexes according to desk.

Amazon Cloud Computing Interview Questions
Question 18. What Are Api Calls Supported By A Global Secondary Index?

Answer :

“Query” and “Scan” are the API calls that are supported through Global Secondary Index.

Oracle Interview Questions
Question 19. How To Delete A Global Secondary Index In Amazon Dynamodb?

Answer :

A Global secondary index may be deleted from the console or through an API call.
Select the desk from that you want to delete the Global Secondary index at the console, pick the “indexes” tab underneath “Table gadgets” after which click on on the “Delete” button that is subsequent to the delete index.
A Global Secondary Index can also be deleted using the Update Table API name.
Question 20. What Are Local Secondary Indexes?

Answer :

An index with the equal partition key because the table but special sort secret is known as nearby secondary index.
A local secondary index is considered to be “nearby” because every partition of a neighborhood secondary index is scaled to a desk partition which incorporates the identical partition key.
Aws Cloudwatch Interview Questions
Question 21. What Are Projections?

Answer :

Projections are the set of attributes which might be copied or projected from the desk to an index.
They are further to the index key attributes and primary key attributes which might be routinely projected.
Whenever you outline a nearby secondary index, it's miles required to specify the attributes which might be projected into the index.
Each index includes not less than 3 attributes.

 They are:

Table partition key fee
Attribute to function the index type key
Table sort key fee
Question 22. How To Create Local Secondary Indexes?

Answer :

A Local secondary index desires to be created at the time of creating a desk which can’t be brought currently.

So, later whilst you create a neighborhood secondary index, try specifying the following two parameters.

Indexed Sort Key :

The characteristic on which indexing and querying are done.

Projected Attributes :

It is the listing of attributes from the table that may without delay be copied into the local secondary index. Without projected attributes, the local secondary index consists of best number one keys and secondary keys.

Question 23. Can I Add Local Secondary Indexes To An Existing Table?

Answer :

When you create a desk with local secondary indexes, you may create a local secondary index to apply it in future by defining a sort key element which isn't always used presently.
So, presently it is probably not feasible to add nearby secondary indexes within the current desk.
AWS Database Interview Questions
Question 24. How Many Local Secondary Indexes Can Be Created On One Table?

Answer :

Each desk can represent as much as 5 local secondary indexes.

MySQL Interview Questions
Question 25. Can I Delete Local Secondary Indexes?

Answer :

Currently, the Amazon DynamoDB is incapable of doing away with the nearby secondary indexes from the desk once they may be created, however it is viable to delete the complete desk.