risingwave_frontend/optimizer/rule/
apply_over_window_transpose_rule.rs

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 risingwave_pb::plan_common::JoinType;
16
17use super::{BoxedRule, Rule};
18use crate::expr::InputRef;
19use crate::optimizer::PlanRef;
20use crate::optimizer::plan_node::{LogicalApply, LogicalFilter, LogicalOverWindow};
21use crate::utils::Condition;
22
23/// Transpose `LogicalApply` and `LogicalOverWindow`.
24///
25/// Before:
26///
27/// ```text
28///     LogicalApply
29///    /            \
30///  Domain    LogicalOverWindow
31///                  |
32///                Input
33/// ```
34///
35/// After:
36///
37/// ```text
38///    LogicalOverWindow
39///          |
40///     LogicalApply
41///    /            \
42///  Domain        Input
43/// ```
44pub struct ApplyOverWindowTransposeRule {}
45impl Rule for ApplyOverWindowTransposeRule {
46    fn apply(&self, plan: PlanRef) -> Option<PlanRef> {
47        let apply: &LogicalApply = plan.as_logical_apply()?;
48        let (left, right, on, join_type, correlated_id, correlated_indices, max_one_row) =
49            apply.clone().decompose();
50        assert_eq!(join_type, JoinType::Inner);
51        let over_window: &LogicalOverWindow = right.as_logical_over_window()?;
52        let (window_input, mut window_functions) = over_window.clone().decompose();
53
54        if max_one_row {
55            return None;
56        }
57
58        let apply_left_len = left.schema().len();
59        let apply_left_schema = left.schema().clone();
60
61        let new_apply = LogicalApply::create(
62            left,
63            window_input,
64            JoinType::Inner,
65            Condition::true_cond(),
66            correlated_id,
67            correlated_indices,
68            false,
69        );
70
71        let new_over_window = {
72            // Shift index of window functions' `InputRef` with `apply_left_len`.
73            // Add domain
74            window_functions.iter_mut().for_each(|func| {
75                func.args
76                    .iter_mut()
77                    .for_each(|arg| arg.shift_with_offset(apply_left_len as isize));
78                func.order_by
79                    .iter_mut()
80                    .for_each(|c| c.column_index += apply_left_len);
81                func.partition_by
82                    .iter_mut()
83                    .for_each(|x| x.shift_with_offset(apply_left_len as isize));
84                // Add the domain columns to the partition by clauses.
85                func.partition_by = (0..apply_left_len)
86                    .map(|i| InputRef::new(i, apply_left_schema.fields[i].data_type()))
87                    .chain(func.partition_by.drain(..))
88                    .collect();
89            });
90
91            LogicalOverWindow::new(window_functions, new_apply)
92        };
93
94        let filter = LogicalFilter::create(new_over_window.into(), on);
95        Some(filter)
96    }
97}
98
99impl ApplyOverWindowTransposeRule {
100    pub fn create() -> BoxedRule {
101        Box::new(ApplyOverWindowTransposeRule {})
102    }
103}
risingwave_frontend/optimizer/rule/apply_over_window_transpose_rule.rs

risingwave_frontend/optimizer/rule/
apply_over_window_transpose_rule.rs
