risingwave_stream::executor::top_n::top_n_cache

Trait AppendOnlyTopNCacheTrait

Source 
pub trait AppendOnlyTopNCacheTrait {
    // Required method
    fn insert<S: StateStore>(
        &mut self,
        cache_key: (Vec<u8>, Vec<u8>),
        row_ref: RowRef<'_>,
        staging: &mut TopNStaging,
        managed_state: &mut ManagedTopNState<S>,
        row_deserializer: &RowDeserializer,
    ) -> StreamExecutorResult<()>;
}
Expand description

Similar to TopNCacheTrait, but for append-only TopN.

Required Methods§

Source

fn insert<S: StateStore>( &mut self, cache_key: (Vec<u8>, Vec<u8>), row_ref: RowRef<'_>, staging: &mut TopNStaging, managed_state: &mut ManagedTopNState<S>, row_deserializer: &RowDeserializer, ) -> StreamExecutorResult<()>

Insert input row to corresponding cache range according to its order key.

Changes in self.middle is recorded to res_ops and res_rows, which will be used to generate messages to be sent to downstream operators.

managed_state is required because different from normal TopN, append-only TopN doesn’t insert all rows into the state table.

Dyn Compatibility§

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors§