Module datafusion::physical_optimizer::join_selection

The JoinSelection rule tries to modify a given plan so that it can accommodate infinite sources and utilize statistical information (if there is any) to obtain more performant plans. To achieve the first goal, it tries to transform a non-runnable query (with the given infinite sources) into a runnable query by replacing pipeline-breaking join operations with pipeline-friendly ones. To achieve the second goal, it selects the proper PartitionMode and the build side using the available statistics for hash joins.

Structs

• JoinSelection
  The JoinSelection rule tries to modify a given plan so that it can accommodate infinite sources and optimize joins in the plan according to available statistical information, if there is any.

Functions

• swap_hash_join
  This function swaps the inputs of the given join operator. This function is public so other downstream projects can use it to construct HashJoinExec with right side as the build side.

Type Aliases

• PipelineFixerSubrule
  Pipeline-fixing join selection subrule.