Struct JoinExecutor 

pub struct JoinExecutor {}

Modern streaming join executor.

Uses Volcano-style operators for efficient join execution with:

• Streaming probe side (no full materialization)
• Early termination for LIMIT
• Residual filter application during iteration

Implementations

impl JoinExecutor

pub fn new() -> Self

Create a new join executor.

pub fn execute(&self, request: JoinRequest<'_>) -> Result<JoinResult>

Execute a join operation.

This is the main entry point that:

1. Analyzes the join condition
2. Uses provided algorithm hint or selects optimal algorithm
3. Executes with streaming
4. Applies early termination

pub fn execute_streaming( &self, request: StreamingJoinRequest<'_>, ) -> Result<JoinResult>

Execute a streaming hash join where probe side streams from an operator.

This is the optimized path for LIMIT queries:

• Build side is materialized (required for hash table)
• Probe side streams row-by-row (O(1) memory)
• Early termination stops probe scan immediately when LIMIT is reached

Performance

For SELECT ... JOIN ... LIMIT 10:

• Old path: Materialize 10M + 10M rows, then return 10
• This path: Materialize 10M rows, stream until 10 matches

Memory usage is halved, and early termination actually stops work.

pub fn execute_streaming_result( &self, request: StreamingJoinRequest<'_>, ) -> Result<StreamingJoinResult>

Return a pull cursor over one hash edge without collecting its output. The cursor itself enforces LIMIT and closes the whole child pipeline on EOF, cancellation, error, early limit, or drop.

Trait Implementations

impl Default for JoinExecutor

fn default() -> Self

Returns the “default value” for a type.