risingwave_frontend/optimizer/plan_node/
batch_max_one_row.rs

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1// Copyright 2025 RisingWave Labs
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
15use pretty_xmlish::XmlNode;
16use risingwave_pb::batch_plan::MaxOneRowNode;
17use risingwave_pb::batch_plan::plan_node::NodeBody;
18
19use super::batch::prelude::*;
20use super::generic::DistillUnit;
21use super::utils::Distill;
22use super::{
23    ExprRewritable, PlanBase, PlanRef, PlanTreeNodeUnary, ToBatchPb, ToDistributedBatch, generic,
24};
25use crate::error::Result;
26use crate::optimizer::plan_node::ToLocalBatch;
27use crate::optimizer::plan_node::expr_visitable::ExprVisitable;
28use crate::optimizer::property::{Order, RequiredDist};
29
30/// [`BatchMaxOneRow`] fetches up to one row from the input, returning an error
31/// if the input contains more than one row at runtime.
32#[derive(Debug, Clone, PartialEq, Eq, Hash)]
33pub struct BatchMaxOneRow {
34    pub base: PlanBase<Batch>,
35    core: generic::MaxOneRow<PlanRef>,
36}
37
38impl BatchMaxOneRow {
39    pub fn new(core: generic::MaxOneRow<PlanRef>) -> Self {
40        let base = PlanBase::new_batch_with_core(
41            &core,
42            core.input.distribution().clone(),
43            core.input.order().clone(),
44        );
45        BatchMaxOneRow { base, core }
46    }
47}
48
49impl PlanTreeNodeUnary for BatchMaxOneRow {
50    fn input(&self) -> PlanRef {
51        self.core.input.clone()
52    }
53
54    fn clone_with_input(&self, input: PlanRef) -> Self {
55        let core = generic::MaxOneRow { input };
56
57        Self::new(core)
58    }
59}
60impl_plan_tree_node_for_unary! {BatchMaxOneRow}
61
62impl Distill for BatchMaxOneRow {
63    fn distill<'a>(&self) -> XmlNode<'a> {
64        self.core.distill_with_name("BatchMaxOneRow")
65    }
66}
67
68impl ToDistributedBatch for BatchMaxOneRow {
69    fn to_distributed(&self) -> Result<PlanRef> {
70        let new_input = RequiredDist::single()
71            .enforce_if_not_satisfies(self.input().to_distributed()?, &Order::any())?;
72        Ok(self.clone_with_input(new_input).into())
73    }
74}
75
76impl ToBatchPb for BatchMaxOneRow {
77    fn to_batch_prost_body(&self) -> NodeBody {
78        NodeBody::MaxOneRow(MaxOneRowNode {})
79    }
80}
81
82impl ToLocalBatch for BatchMaxOneRow {
83    fn to_local(&self) -> Result<PlanRef> {
84        let new_input = RequiredDist::single()
85            .enforce_if_not_satisfies(self.input().to_local()?, &Order::any())?;
86        Ok(self.clone_with_input(new_input).into())
87    }
88}
89
90impl ExprRewritable for BatchMaxOneRow {}
91
92impl ExprVisitable for BatchMaxOneRow {}
risingwave_frontend/optimizer/plan_node/batch_max_one_row.rs

risingwave_frontend/optimizer/plan_node/
batch_max_one_row.rs
