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Documentation
Using the Documentation
Pipeline development lifecycle
Beam programming guide
- Overview
- Pipelines
- PCollections
  - Creating a PCollection
  - PCollection characteristics
- Transforms
  - Applying transforms
  - Core Beam transforms
    - ParDo
    - GroupByKey
    - CoGroupByKey
    - Combine
    - Flatten
    - Partition
  - Requirements for user code
  - Side inputs
  - Additional outputs
  - Composite transforms
- Pipeline I/O
  - Using I/O transforms
  - Built-in I/O connectors
  - Developing new I/O connectors
  - Testing I/O transforms
- Data encoding and type safety
- Windowing
- Triggers
- Metrics
Transform catalog
- Python
  - Overview
  - Element-wise
    - Filter
    - FlatMap
    - Keys
    - KvSwap
    - Map
    - ParDo
    - Partition
    - Regex
    - Reify
    - ToString
    - Values
    - WithTimestamps
  - Aggregation
    - CoGroupByKey
    - CombineGlobally
    - Count
    - Distinct
    - GroupByKey
    - Mean
    - Sample
    - Top
  - Other
    - Create
    - Flatten
    - Reshuffle
    - WindowInto
- Java
  - Overview
  - Element-wise
    - Filter
    - FlatMapElements
    - Keys
    - KvSwap
    - MapElements
    - ParDo
    - Partition
    - Regex
    - Reify
    - Values
    - ToString
    - WithKeys
    - WithTimestamps
  - Aggregation
    - ApproximateQuantiles
    - ApproximateUnique
    - CoGroupByKey
    - Combine
    - CombineWithContext
    - Count
    - Distinct
    - GroupByKey
    - GroupIntoBatches
    - HllCount
    - Latest
    - Max
    - Mean
    - Min
    - Sample
    - Sum
    - Top
  - Other
    - Create
    - Flatten
    - PAssert
    - View
    - Window
Common pipeline patterns
Runtime systems
Learning resources
Beam Wiki

Examples
Related transforms

Distinct

Produces a collection containing distinct elements of the input collection.

Examples

See BEAM-7390 for updates.

Related transforms

Count counts the number of elements within each aggregation.

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