Package org.apache.flink.table.connector

Interface ParallelismProvider

All Known Subinterfaces:
InputFormatProvider, OutputFormatProvider, SinkV2Provider, SourceProvider
@PublicEvolving public interface ParallelismProvider
Parallelism provider for other connector providers. It allows to express a custom parallelism for the connector runtime implementation. Otherwise, the parallelism is determined by the planner.

  • Method Summary

    Modifier and Type
    Method
    Description
    default Optional<Integer>
    getParallelism()
    Returns the parallelism for this instance.

  • Method Details

    • getParallelism

      default Optional<Integer> getParallelism()
      Returns the parallelism for this instance.

      The parallelism denotes how many parallel instances of a source or sink will be spawned during the execution.

      Enforcing a different parallelism for sources/sinks might mess up the changelog if the output/input is not ChangelogMode.insertOnly(). Therefore, a primary key is required by which the output/input will be shuffled after/before records leave/enter the ScanTableSource.ScanRuntimeProvider/DynamicTableSink.SinkRuntimeProvider implementation.

      Returns:
      empty if the connector does not provide a custom parallelism, then the planner will decide the number of parallel instances by itself.