---
title: Apache Flink Documentation 
type: docs
bookToc: false
aliases:
  - /examples/index.html
  - /getting-started/examples/index.html
  - /dev/execution_plans.html
  - /docs/dev/execution/execution_plans/
---
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# Apache Flink Documentation

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**Apache Flink** is a framework and distributed processing engine for stateful computations over *unbounded* and *bounded* data streams. Flink has been designed to run in *all common cluster environments*, perform computations at *in-memory* speed and at *any scale*.
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### Try Flink

If you're interested in playing around with Flink, try one of our tutorials:

* [Flink SQL Tutorial]({{< ref "docs/getting-started/quickstart-sql" >}}) - Interactive queries with the SQL Client
* [Table API Tutorial]({{< ref "docs/getting-started/table_api" >}}) - Declarative streaming with a relational API
* [DataStream API Tutorial]({{< ref "docs/getting-started/datastream" >}}) - Imperative, event-driven stream processing
* [Operations Playground]({{< ref "docs/getting-started/flink-operations-playground" >}}) - Explore Flink in Docker

### Learn Flink

* To dive in deeper, the [Hands-on Training]({{< ref "docs/learn-flink/overview" >}}) includes a set of lessons and exercises that provide a step-by-step introduction to Flink.

* The [Concepts]({{< ref "docs/concepts/overview" >}}) section explains what you need to know about Flink before exploring the reference documentation.

### Get Help with Flink

If you get stuck, check out our [community support resources](https://flink.apache.org/community.html). In particular, Apache Flink’s user mailing list is consistently ranked as one of the most active of any Apache project, and is a great way to get help quickly.

<--->

### Explore Flink

The reference documentation covers all the details. Some starting points:

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* [Flink SQL]({{< ref "docs/sql/overview" >}})
* [Table API]({{< ref "docs/dev/table/overview" >}})
* [DataStream API]({{< ref "docs/dev/datastream/overview" >}})
* [DataStream API (V2)]({{< ref "docs/dev/datastream-v2/overview" >}})

<--->

* [Configuration]({{< ref "docs/deployment/config" >}})
* [REST API]({{< ref "docs/ops/rest_api" >}})
* [CLI]({{< ref "docs/deployment/cli" >}})
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### Deploy Flink

Before putting your Flink job into production, read the [Production Readiness Checklist]({{< ref "docs/ops/production_ready" >}}).
For an overview of possible deployment targets, see [Clusters and Deployments]({{< ref "docs/deployment/overview" >}}).

### Upgrade Flink

Release notes cover important changes between Flink versions. Please read them carefully if you plan to upgrade your Flink setup.

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For some reason Hugo will only allow linking to the 
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See the release notes for
[Flink 2.2]({{< ref "/release-notes/flink-2.2.md" >}}),
[Flink 2.1]({{< ref "/release-notes/flink-2.1.md" >}}),
[Flink 2.0]({{< ref "/release-notes/flink-2.0.md" >}}),
[Flink 1.20]({{< ref "/release-notes/flink-1.20.md" >}}),
[Flink 1.19]({{< ref "/release-notes/flink-1.19.md" >}}),
[Flink 1.18]({{< ref "/release-notes/flink-1.18.md" >}}),
[Flink 1.17]({{< ref "/release-notes/flink-1.17.md" >}}),
[Flink 1.16]({{< ref "/release-notes/flink-1.16.md" >}}), 
[Flink 1.15]({{< ref "/release-notes/flink-1.15.md" >}}), 
[Flink 1.14]({{< ref "/release-notes/flink-1.14.md" >}}), 
[Flink 1.13]({{< ref "/release-notes/flink-1.13.md" >}}), 
[Flink 1.12]({{< ref "/release-notes/flink-1.12.md" >}}), 
[Flink 1.11]({{< ref "/release-notes/flink-1.11.md" >}}), 
[Flink 1.10]({{< ref "/release-notes/flink-1.10.md" >}}), 
[Flink 1.9]({{< ref "/release-notes/flink-1.9.md" >}}), 
[Flink 1.8]({{< ref "/release-notes/flink-1.8.md" >}}), or 
[Flink 1.7]({{< ref "/release-notes/flink-1.7.md" >}}).

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