Exploring AWS !!

Day 46:

Amazon DynamoDB - Part 2

DynamoDB Streams: Capture data modification events, the data about these events appear in stream in near real time and in order that events occur. Stream records have 24 hours lifetime.
Example:Consider customer table that contains customer information for a company. Suppose sending mail enable stream on that table and then associate stream with lambda function. Lambda would run whenever a new stream record appears, but only process new items added to customer's table. For any item having EmailAddress attribute, lambda would invoke SES to send an email to address.

Control Plane: Create Table, DescribeTable, ListTable, UpdateTable, DeleteTable - lets you manage and create DynamoDB tables.
Data Plane: operation lets you create, read, update and delete (CRUD) actions on tab.

You can use PartiQL-SQL compatible query language to perform CRUD
Creating data: PutItem, BatchWriteItem, - up to 25 items
Reading data: BatchItem, GetItem, Query, Scan
Updating Item: UpdateItem
Deleting Item: DeleteItem, BatchWriteItem
Transaction provide ACID (atomicity, consistency, isolation, durability)
Data types for attributes: scalar, document, set

Read consistency: Eventually consistent read, strongly consistent read
Eventually consistent read: responses may not reflect results recently completed write operation, but if we repeat read request after sometime it returns more recent ones.
Strongly consistent read: GetItem, scan and query provide consistent read parameters, if set to true returns most recent up-to-date data.