Buffering functions

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Sink, combine, source — for output that depends on the whole input.

trait TableBufferingFunction

source

pub trait TableBufferingFunction: Send + Sync {
  fn name(&self) -> &str;
  fn metadata(&self) -> FunctionMetadata;
  fn argument_specs(&self) -> Vec<ArgSpec>;
  fn secret_lookups(&self, _params: &BindParams) -> Vec<crate::secrets::SecretLookup> {
      Vec::new()
  }
  fn on_bind(&self, params: &BindParams) -> Result<BindResponse>;
  fn process(
      &self,
      params: &BufferingParams,
      batch: &arrow_array::RecordBatch,
  ) -> Result<Vec<u8>>;
  fn combine(&self, params: &BufferingParams, state_ids: &[Vec<u8>]) -> Result<Vec<Vec<u8>>>;
  fn finalize_producer(
      &self,
      params: &BufferingParams,
      finalize_state_id: Vec<u8>,
  ) -> Result<Box<dyn TableProducer>>;
}

Description

A table buffering (sink+source) function.

struct BufferingParams

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pub struct BufferingParams {
  pub execution_id: Vec<u8>,
  pub storage: Arc<dyn FunctionStorage>,
  pub output_schema: SchemaRef,
  pub arguments: Arguments,
  pub settings: Settings,
  pub secrets: crate::secrets::Secrets,
  pub attach_opaque_data: Option<Vec<u8>>,
  pub batch_index: Option<i64>,
  pub copy_to: Option<crate::protocol::dtos::CopyToContext>,
  pub input_schema: Option<SchemaRef>,
  pub logs: Arc<std::sync::Mutex<Vec<String>>>,
}

Description

Parameters for buffering process / combine / finalize.

Methods

method log

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pub fn log(&self, message: impl Into<String>)

Queue an INFO-level client log line (surfaced under duckdb_logs()).