flow/expr/
relation.rs

1// Copyright 2023 Greptime Team
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//     http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15//! Describes an aggregation function and it's input expression.
16
17pub(crate) use accum::{Accum, Accumulator};
18pub(crate) use func::AggregateFunc;
19
20use crate::expr::ScalarExpr;
21
22mod accum;
23mod func;
24
25/// Describes an aggregation expression.
26#[derive(Clone, Debug, Eq, PartialEq, Ord, PartialOrd)]
27pub struct AggregateExpr {
28    /// Names the aggregation function.
29    pub func: AggregateFunc,
30    /// An expression which extracts from each row the input to `func`.
31    /// TODO(discord9): currently unused in render phase(because AccumulablePlan remember each Aggr Expr's input/output column),
32    /// so it only used in generate KeyValPlan from AggregateExpr
33    pub expr: ScalarExpr,
34    /// Should the aggregation be applied only to distinct results in each group.
35    pub distinct: bool,
36}
flow/expr/relation.rs

flow/expr/
relation.rs
