risingwave_frontend/expr/
order_by_expr.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 std::fmt::Display;
16
17use itertools::Itertools;
18use risingwave_common::util::sort_util::OrderType;
19
20use crate::expr::{ExprImpl, ExprMutator, ExprRewriter, ExprVisitor};
21
22/// A sort expression in the `ORDER BY` clause.
23///
24/// See also [`bind_order_by_expr`](`crate::binder::Binder::bind_order_by_expr`).
25#[derive(Clone, Eq, PartialEq, Hash, Debug)]
26pub struct OrderByExpr {
27    pub expr: ExprImpl,
28    pub order_type: OrderType,
29}
30
31impl Display for OrderByExpr {
32    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
33        write!(f, "{:?} {}", self.expr, self.order_type)?;
34        Ok(())
35    }
36}
37
38/// See [`OrderByExpr`].
39#[derive(Clone, Eq, PartialEq, Hash, Debug)]
40pub struct OrderBy {
41    pub sort_exprs: Vec<OrderByExpr>,
42}
43
44impl Display for OrderBy {
45    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
46        write!(f, "ORDER BY {}", self.sort_exprs.iter().format(", "))
47    }
48}
49
50impl OrderBy {
51    pub fn any() -> Self {
52        Self {
53            sort_exprs: Vec::new(),
54        }
55    }
56
57    pub fn new(sort_exprs: Vec<OrderByExpr>) -> Self {
58        Self { sort_exprs }
59    }
60
61    pub fn rewrite_expr(self, rewriter: &mut (impl ExprRewriter + ?Sized)) -> Self {
62        Self {
63            sort_exprs: self
64                .sort_exprs
65                .into_iter()
66                .map(|e| OrderByExpr {
67                    expr: rewriter.rewrite_expr(e.expr),
68                    order_type: e.order_type,
69                })
70                .collect(),
71        }
72    }
73
74    pub fn visit_expr<V: ExprVisitor + ?Sized>(&self, visitor: &mut V) {
75        self.sort_exprs
76            .iter()
77            .for_each(|expr| visitor.visit_expr(&expr.expr));
78    }
79
80    pub fn visit_expr_mut(&mut self, mutator: &mut (impl ExprMutator + ?Sized)) {
81        self.sort_exprs
82            .iter_mut()
83            .for_each(|expr| mutator.visit_expr(&mut expr.expr))
84    }
85}
risingwave_frontend/expr/order_by_expr.rs

risingwave_frontend/expr/
order_by_expr.rs
