datafusion_python/expr/
limit.rs

1// Licensed to the Apache Software Foundation (ASF) under one
2// or more contributor license agreements.  See the NOTICE file
3// distributed with this work for additional information
4// regarding copyright ownership.  The ASF licenses this file
5// to you under the Apache License, Version 2.0 (the
6// "License"); you may not use this file except in compliance
7// with the License.  You may obtain a copy of the License at
8//
9//   http://www.apache.org/licenses/LICENSE-2.0
10//
11// Unless required by applicable law or agreed to in writing,
12// software distributed under the License is distributed on an
13// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
14// KIND, either express or implied.  See the License for the
15// specific language governing permissions and limitations
16// under the License.
17
18use std::fmt::{self, Display, Formatter};
19
20use datafusion::logical_expr::logical_plan::Limit;
21use pyo3::IntoPyObjectExt;
22use pyo3::prelude::*;
23
24use crate::common::df_schema::PyDFSchema;
25use crate::expr::logical_node::LogicalNode;
26use crate::sql::logical::PyLogicalPlan;
27
28#[pyclass(
29    from_py_object,
30    frozen,
31    name = "Limit",
32    module = "datafusion.expr",
33    subclass
34)]
35#[derive(Clone)]
36pub struct PyLimit {
37    limit: Limit,
38}
39
40impl From<Limit> for PyLimit {
41    fn from(limit: Limit) -> PyLimit {
42        PyLimit { limit }
43    }
44}
45
46impl From<PyLimit> for Limit {
47    fn from(limit: PyLimit) -> Self {
48        limit.limit
49    }
50}
51
52impl Display for PyLimit {
53    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
54        write!(
55            f,
56            "Limit
57            Skip: {:?}
58            Fetch: {:?}
59            Input: {:?}",
60            &self.limit.skip, &self.limit.fetch, &self.limit.input
61        )
62    }
63}
64
65#[pymethods]
66impl PyLimit {
67    // NOTE: Upstream now has expressions for skip and fetch
68    // TODO: Do we still want to expose these?
69    // REF: https://github.com/apache/datafusion/pull/12836
70
71    // /// Retrieves the skip value for this `Limit`
72    // fn skip(&self) -> usize {
73    //     self.limit.skip
74    // }
75
76    // /// Retrieves the fetch value for this `Limit`
77    // fn fetch(&self) -> Option<usize> {
78    //     self.limit.fetch
79    // }
80
81    /// Retrieves the input `LogicalPlan` to this `Limit` node
82    fn input(&self) -> PyResult<Vec<PyLogicalPlan>> {
83        Ok(Self::inputs(self))
84    }
85
86    /// Resulting Schema for this `Limit` node instance
87    fn schema(&self) -> PyResult<PyDFSchema> {
88        Ok(self.limit.input.schema().as_ref().clone().into())
89    }
90
91    fn __repr__(&self) -> PyResult<String> {
92        Ok(format!("Limit({self})"))
93    }
94}
95
96impl LogicalNode for PyLimit {
97    fn inputs(&self) -> Vec<PyLogicalPlan> {
98        vec![PyLogicalPlan::from((*self.limit.input).clone())]
99    }
100
101    fn to_variant<'py>(&self, py: Python<'py>) -> PyResult<Bound<'py, PyAny>> {
102        self.clone().into_bound_py_any(py)
103    }
104}
datafusion_python/expr/limit.rs

datafusion_python/expr/
limit.rs
