Struct QueryResultOperator 

pub struct QueryResultOperator { /* private fields */ }

Operator that streams rows from a QueryResult.

This adapter allows existing QueryResult (from table scans, etc.) to be used in the streaming operator pipeline. Unlike MaterializedOperator, this does NOT load all rows upfront - it streams them on demand.

Benefits

• Memory efficient: Only one row in memory at a time
• Early termination: LIMIT stops reading immediately
• Streaming pipeline: Fits into Volcano execution model

Implementations

impl QueryResultOperator

pub fn new(result: Box<dyn StorageQueryResult>, columns: Vec<String>) -> Self

Create a new streaming operator from a QueryResult.

Trait Implementations

impl Operator for QueryResultOperator

fn open(&mut self) -> Result<()>

Initialize the operator.

fn next(&mut self) -> Result<Option<RowRef>>

Get the next row from this operator.

fn close(&mut self) -> Result<()>

Close the operator and release resources.

fn schema(&self) -> &[ColumnInfo]

Get the schema (column information) for this operator’s output.

fn estimated_rows(&self) -> Option<usize>

Get an estimate of the number of rows this operator will produce.

fn ordering(&self) -> OrderingProperty

Physical ordering guaranteed by this operator’s output.

fn name(&self) -> &str

Get a descriptive name for this operator (for EXPLAIN).