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::prelude::*;
22use pyo3::IntoPyObjectExt;
23
24use crate::common::df_schema::PyDFSchema;
25use crate::expr::logical_node::LogicalNode;
26use crate::sql::logical::PyLogicalPlan;
27
28#[pyclass(frozen, name = "Limit", module = "datafusion.expr", subclass)]
29#[derive(Clone)]
30pub struct PyLimit {
31    limit: Limit,
32}
33
34impl From<Limit> for PyLimit {
35    fn from(limit: Limit) -> PyLimit {
36        PyLimit { limit }
37    }
38}
39
40impl From<PyLimit> for Limit {
41    fn from(limit: PyLimit) -> Self {
42        limit.limit
43    }
44}
45
46impl Display for PyLimit {
47    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
48        write!(
49            f,
50            "Limit
51            Skip: {:?}
52            Fetch: {:?}
53            Input: {:?}",
54            &self.limit.skip, &self.limit.fetch, &self.limit.input
55        )
56    }
57}
58
59#[pymethods]
60impl PyLimit {
61    // NOTE: Upstream now has expressions for skip and fetch
62    // TODO: Do we still want to expose these?
63    // REF: https://github.com/apache/datafusion/pull/12836
64
65    // /// Retrieves the skip value for this `Limit`
66    // fn skip(&self) -> usize {
67    //     self.limit.skip
68    // }
69
70    // /// Retrieves the fetch value for this `Limit`
71    // fn fetch(&self) -> Option<usize> {
72    //     self.limit.fetch
73    // }
74
75    /// Retrieves the input `LogicalPlan` to this `Limit` node
76    fn input(&self) -> PyResult<Vec<PyLogicalPlan>> {
77        Ok(Self::inputs(self))
78    }
79
80    /// Resulting Schema for this `Limit` node instance
81    fn schema(&self) -> PyResult<PyDFSchema> {
82        Ok(self.limit.input.schema().as_ref().clone().into())
83    }
84
85    fn __repr__(&self) -> PyResult<String> {
86        Ok(format!("Limit({self})"))
87    }
88}
89
90impl LogicalNode for PyLimit {
91    fn inputs(&self) -> Vec<PyLogicalPlan> {
92        vec![PyLogicalPlan::from((*self.limit.input).clone())]
93    }
94
95    fn to_variant<'py>(&self, py: Python<'py>) -> PyResult<Bound<'py, PyAny>> {
96        self.clone().into_bound_py_any(py)
97    }
98}
datafusion_python/expr/limit.rs

datafusion_python/expr/
limit.rs
