# flink_notes

**Repository Path**: aidysun/flink_notes

## Basic Information

- **Project Name**: flink_notes
- **Description**: No description available
- **Primary Language**: Unknown
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 1
- **Forks**: 0
- **Created**: 2019-07-31
- **Last Updated**: 2020-12-19

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# flink

* Definition
  * It's a **framework** and **distributed** processing engine for **stateful** computations over **unbounded and bounded data streams**.

<!-- MarkdownTOC autolink=true levels=1,2,3 -->

- [Flink Application](#flink-application)
	- [Streams](#streams)
	- [State](#state)
	- [Time](#time)
	- [API](#api)
- [Flink Architecture](#flink-architecture)
	- [unbounded and bounded data stream](#unbounded-and-bounded-data-stream)
	- [flexible deployment](#flexible-deployment)
	- [scalability](#scalability)
	- [high performance](#high-performance)
- [Flink Scenario](#flink-scenario)

<!-- /MarkdownTOC -->

## Flink Application  

### Streams
  * unbounded
  * bounded

### State
  * stateful computations
  * state is a first-class citizen in Flink
  * exactly-once

### Time
  * Event time      - event/data created time
  * Ingestion time  - the time when an event enters the Flink dataflow
  * Processing time - local time at each operator that performs an operation

### API
  * SQL/Table API (dynamic tables)
    * Analytics API
  * DataStream API (streams, windows)
    * Stream & batch data processing
  * ProcessFunction (event, state, time)
    * Stateful event-driven applications

## Flink Architecture

### unbounded and bounded data stream

### flexible deployment
* Yam, K8S

### scalability
* 1.7 billion/s

### high performance
* local state, less network IO
  * persistent to remote store regularly

## Flink Scenario

* Data Pipeline
  * ETL (extract-transform-load) in Kafaka
  * real-time data storage
* Data Analytics 
  * realtime 
* Data Driven
  * risk control - rules