Struct tidb_query_executors::stream_aggr_executor::BatchStreamAggregationImpl

pub struct BatchStreamAggregationImpl {
    group_by_exps: Vec<RpnExpression>,
    group_by_exps_types: Vec<EvalType>,
    group_by_field_type: Vec<FieldType>,
    keys: Vec<ScalarValue>,
    states: Vec<Box<dyn AggrFunctionState>>,
    group_by_results_unsafe: Vec<RpnStackNode<'static>>,
    aggr_expr_results_unsafe: Vec<RpnStackNode<'static>>,
}

Fields

group_by_exps: Vec<RpnExpression>

group_by_exps_types: Vec<EvalType>

used in the iterate_each_group_for_aggregation method

group_by_field_type: Vec<FieldType>

keys: Vec<ScalarValue>

Stores all group keys for the current result partial. The last group_by_exps.len() elements are the keys of the last group.

states: Vec<Box<dyn AggrFunctionState>>

Stores all group states for the current result partial. The last each_aggr_fn.len() elements are the states of the last group.

group_by_results_unsafe: Vec<RpnStackNode<'static>>

Stores evaluation results of group by expressions. It is just used to reduce allocations. The lifetime is not really ’static. The elements are only valid in the same batch where they are added.

aggr_expr_results_unsafe: Vec<RpnStackNode<'static>>

Stores evaluation results of aggregate expressions. It is just used to reduce allocations. The lifetime is not really ’static. The elements are only valid in the same batch where they are added.

Trait Implementations

impl<Src: BatchExecutor> AggregationExecutorImpl<Src> for BatchStreamAggregationImpl

fn prepare_entities(&mut self, entities: &mut Entities<Src>)

Accepts entities without any group by columns and modifies them optionally.

fn process_batch_input(
    &mut self,
    entities: &mut Entities<Src>,
    input_physical_columns: LazyBatchColumnVec,
    input_logical_rows: &[usize]
) -> Result<()>

Processes a set of columns which are emitted from the underlying executor.

fn groups_len(&self) -> usize

Note that the partial group is in count.

fn iterate_available_groups(
    &mut self,
    entities: &mut Entities<Src>,
    src_is_drained: bool,
    iteratee: impl FnMut(&mut Entities<Src>, &[Box<dyn AggrFunctionState>]) -> Result<()>
) -> Result<Vec<LazyBatchColumn>>

Iterates aggregate function states for each available group.

fn is_partial_results_ready(&self) -> bool

We cannot ensure the last group is complete, so we can output partial results only if group count >= 2.