datafusion_python/
expr.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::collections::HashMap;
19use std::convert::{From, Into};
20use std::sync::Arc;
21
22use datafusion::arrow::datatypes::{DataType, Field};
23use datafusion::arrow::pyarrow::PyArrowType;
24use datafusion::functions::core::expr_ext::FieldAccessor;
25use datafusion::logical_expr::expr::{
26    AggregateFunction, AggregateFunctionParams, FieldMetadata, InList, InSubquery, ScalarFunction,
27    WindowFunction,
28};
29use datafusion::logical_expr::utils::exprlist_to_fields;
30use datafusion::logical_expr::{
31    Between, BinaryExpr, Case, Cast, Expr, ExprFuncBuilder, ExprFunctionExt, Like, LogicalPlan,
32    Operator, TryCast, WindowFunctionDefinition, col, lit, lit_with_metadata,
33};
34use pyo3::IntoPyObjectExt;
35use pyo3::basic::CompareOp;
36use pyo3::prelude::*;
37use window::PyWindowFrame;
38
39use self::alias::PyAlias;
40use self::bool_expr::{
41    PyIsFalse, PyIsNotFalse, PyIsNotNull, PyIsNotTrue, PyIsNotUnknown, PyIsNull, PyIsTrue,
42    PyIsUnknown, PyNegative, PyNot,
43};
44use self::like::{PyILike, PyLike, PySimilarTo};
45use self::scalar_variable::PyScalarVariable;
46use crate::common::data_type::{DataTypeMap, NullTreatment, PyScalarValue, RexType};
47use crate::errors::{PyDataFusionResult, py_runtime_err, py_type_err, py_unsupported_variant_err};
48use crate::expr::aggregate_expr::PyAggregateFunction;
49use crate::expr::binary_expr::PyBinaryExpr;
50use crate::expr::column::PyColumn;
51use crate::expr::literal::PyLiteral;
52use crate::functions::add_builder_fns_to_window;
53use crate::pyarrow_util::scalar_to_pyarrow;
54use crate::sql::logical::PyLogicalPlan;
55
56pub mod aggregate;
57pub mod aggregate_expr;
58pub mod alias;
59pub mod analyze;
60pub mod between;
61pub mod binary_expr;
62pub mod bool_expr;
63pub mod case;
64pub mod cast;
65pub mod column;
66pub mod conditional_expr;
67pub mod copy_to;
68pub mod create_catalog;
69pub mod create_catalog_schema;
70pub mod create_external_table;
71pub mod create_function;
72pub mod create_index;
73pub mod create_memory_table;
74pub mod create_view;
75pub mod describe_table;
76pub mod distinct;
77pub mod dml;
78pub mod drop_catalog_schema;
79pub mod drop_function;
80pub mod drop_table;
81pub mod drop_view;
82pub mod empty_relation;
83pub mod exists;
84pub mod explain;
85pub mod extension;
86pub mod filter;
87pub mod grouping_set;
88pub mod in_list;
89pub mod in_subquery;
90pub mod join;
91pub mod like;
92pub mod limit;
93pub mod literal;
94pub mod logical_node;
95pub mod placeholder;
96pub mod projection;
97pub mod recursive_query;
98pub mod repartition;
99pub mod scalar_subquery;
100pub mod scalar_variable;
101pub mod signature;
102pub mod sort;
103pub mod sort_expr;
104pub mod statement;
105pub mod subquery;
106pub mod subquery_alias;
107pub mod table_scan;
108pub mod union;
109pub mod unnest;
110pub mod unnest_expr;
111pub mod values;
112pub mod window;
113
114use sort_expr::{PySortExpr, to_sort_expressions};
115
116/// A PyExpr that can be used on a DataFrame
117#[pyclass(frozen, name = "RawExpr", module = "datafusion.expr", subclass)]
118#[derive(Debug, Clone)]
119pub struct PyExpr {
120    pub expr: Expr,
121}
122
123impl From<PyExpr> for Expr {
124    fn from(expr: PyExpr) -> Expr {
125        expr.expr
126    }
127}
128
129impl From<Expr> for PyExpr {
130    fn from(expr: Expr) -> PyExpr {
131        PyExpr { expr }
132    }
133}
134
135/// Convert a list of DataFusion Expr to PyExpr
136pub fn py_expr_list(expr: &[Expr]) -> PyResult<Vec<PyExpr>> {
137    Ok(expr.iter().map(|e| PyExpr::from(e.clone())).collect())
138}
139
140#[pymethods]
141impl PyExpr {
142    /// Return the specific expression
143    fn to_variant<'py>(&self, py: Python<'py>) -> PyResult<Bound<'py, PyAny>> {
144        Python::attach(|_| match &self.expr {
145            Expr::Alias(alias) => Ok(PyAlias::from(alias.clone()).into_bound_py_any(py)?),
146            Expr::Column(col) => Ok(PyColumn::from(col.clone()).into_bound_py_any(py)?),
147            Expr::ScalarVariable(field, variables) => {
148                Ok(PyScalarVariable::new(field, variables).into_bound_py_any(py)?)
149            }
150            Expr::Like(value) => Ok(PyLike::from(value.clone()).into_bound_py_any(py)?),
151            Expr::Literal(value, metadata) => Ok(PyLiteral::new_with_metadata(
152                value.clone(),
153                metadata.clone(),
154            )
155            .into_bound_py_any(py)?),
156            Expr::BinaryExpr(expr) => Ok(PyBinaryExpr::from(expr.clone()).into_bound_py_any(py)?),
157            Expr::Not(expr) => Ok(PyNot::new(*expr.clone()).into_bound_py_any(py)?),
158            Expr::IsNotNull(expr) => Ok(PyIsNotNull::new(*expr.clone()).into_bound_py_any(py)?),
159            Expr::IsNull(expr) => Ok(PyIsNull::new(*expr.clone()).into_bound_py_any(py)?),
160            Expr::IsTrue(expr) => Ok(PyIsTrue::new(*expr.clone()).into_bound_py_any(py)?),
161            Expr::IsFalse(expr) => Ok(PyIsFalse::new(*expr.clone()).into_bound_py_any(py)?),
162            Expr::IsUnknown(expr) => Ok(PyIsUnknown::new(*expr.clone()).into_bound_py_any(py)?),
163            Expr::IsNotTrue(expr) => Ok(PyIsNotTrue::new(*expr.clone()).into_bound_py_any(py)?),
164            Expr::IsNotFalse(expr) => Ok(PyIsNotFalse::new(*expr.clone()).into_bound_py_any(py)?),
165            Expr::IsNotUnknown(expr) => {
166                Ok(PyIsNotUnknown::new(*expr.clone()).into_bound_py_any(py)?)
167            }
168            Expr::Negative(expr) => Ok(PyNegative::new(*expr.clone()).into_bound_py_any(py)?),
169            Expr::AggregateFunction(expr) => {
170                Ok(PyAggregateFunction::from(expr.clone()).into_bound_py_any(py)?)
171            }
172            Expr::SimilarTo(value) => Ok(PySimilarTo::from(value.clone()).into_bound_py_any(py)?),
173            Expr::Between(value) => {
174                Ok(between::PyBetween::from(value.clone()).into_bound_py_any(py)?)
175            }
176            Expr::Case(value) => Ok(case::PyCase::from(value.clone()).into_bound_py_any(py)?),
177            Expr::Cast(value) => Ok(cast::PyCast::from(value.clone()).into_bound_py_any(py)?),
178            Expr::TryCast(value) => Ok(cast::PyTryCast::from(value.clone()).into_bound_py_any(py)?),
179            Expr::ScalarFunction(value) => Err(py_unsupported_variant_err(format!(
180                "Converting Expr::ScalarFunction to a Python object is not implemented: {value:?}"
181            ))),
182            Expr::WindowFunction(value) => Err(py_unsupported_variant_err(format!(
183                "Converting Expr::WindowFunction to a Python object is not implemented: {value:?}"
184            ))),
185            Expr::InList(value) => {
186                Ok(in_list::PyInList::from(value.clone()).into_bound_py_any(py)?)
187            }
188            Expr::Exists(value) => Ok(exists::PyExists::from(value.clone()).into_bound_py_any(py)?),
189            Expr::InSubquery(value) => {
190                Ok(in_subquery::PyInSubquery::from(value.clone()).into_bound_py_any(py)?)
191            }
192            Expr::ScalarSubquery(value) => {
193                Ok(scalar_subquery::PyScalarSubquery::from(value.clone()).into_bound_py_any(py)?)
194            }
195            #[allow(deprecated)]
196            Expr::Wildcard { qualifier, options } => Err(py_unsupported_variant_err(format!(
197                "Converting Expr::Wildcard to a Python object is not implemented : {qualifier:?} {options:?}"
198            ))),
199            Expr::GroupingSet(value) => {
200                Ok(grouping_set::PyGroupingSet::from(value.clone()).into_bound_py_any(py)?)
201            }
202            Expr::Placeholder(value) => {
203                Ok(placeholder::PyPlaceholder::from(value.clone()).into_bound_py_any(py)?)
204            }
205            Expr::OuterReferenceColumn(data_type, column) => {
206                Err(py_unsupported_variant_err(format!(
207                    "Converting Expr::OuterReferenceColumn to a Python object is not implemented: {data_type:?} - {column:?}"
208                )))
209            }
210            Expr::Unnest(value) => {
211                Ok(unnest_expr::PyUnnestExpr::from(value.clone()).into_bound_py_any(py)?)
212            }
213        })
214    }
215
216    /// Returns the name of this expression as it should appear in a schema. This name
217    /// will not include any CAST expressions.
218    fn schema_name(&self) -> PyResult<String> {
219        Ok(format!("{}", self.expr.schema_name()))
220    }
221
222    /// Returns a full and complete string representation of this expression.
223    fn canonical_name(&self) -> PyResult<String> {
224        Ok(format!("{}", self.expr))
225    }
226
227    /// Returns the name of the Expr variant.
228    /// Ex: 'IsNotNull', 'Literal', 'BinaryExpr', etc
229    fn variant_name(&self) -> PyResult<&str> {
230        Ok(self.expr.variant_name())
231    }
232
233    fn __richcmp__(&self, other: PyExpr, op: CompareOp) -> PyExpr {
234        let expr = match op {
235            CompareOp::Lt => self.expr.clone().lt(other.expr),
236            CompareOp::Le => self.expr.clone().lt_eq(other.expr),
237            CompareOp::Eq => self.expr.clone().eq(other.expr),
238            CompareOp::Ne => self.expr.clone().not_eq(other.expr),
239            CompareOp::Gt => self.expr.clone().gt(other.expr),
240            CompareOp::Ge => self.expr.clone().gt_eq(other.expr),
241        };
242        expr.into()
243    }
244
245    fn __repr__(&self) -> PyResult<String> {
246        Ok(format!("Expr({})", self.expr))
247    }
248
249    fn __add__(&self, rhs: PyExpr) -> PyResult<PyExpr> {
250        Ok((self.expr.clone() + rhs.expr).into())
251    }
252
253    fn __sub__(&self, rhs: PyExpr) -> PyResult<PyExpr> {
254        Ok((self.expr.clone() - rhs.expr).into())
255    }
256
257    fn __truediv__(&self, rhs: PyExpr) -> PyResult<PyExpr> {
258        Ok((self.expr.clone() / rhs.expr).into())
259    }
260
261    fn __mul__(&self, rhs: PyExpr) -> PyResult<PyExpr> {
262        Ok((self.expr.clone() * rhs.expr).into())
263    }
264
265    fn __mod__(&self, rhs: PyExpr) -> PyResult<PyExpr> {
266        let expr = self.expr.clone() % rhs.expr;
267        Ok(expr.into())
268    }
269
270    fn __and__(&self, rhs: PyExpr) -> PyResult<PyExpr> {
271        Ok(self.expr.clone().and(rhs.expr).into())
272    }
273
274    fn __or__(&self, rhs: PyExpr) -> PyResult<PyExpr> {
275        Ok(self.expr.clone().or(rhs.expr).into())
276    }
277
278    fn __invert__(&self) -> PyResult<PyExpr> {
279        let expr = !self.expr.clone();
280        Ok(expr.into())
281    }
282
283    fn __getitem__(&self, key: &str) -> PyResult<PyExpr> {
284        Ok(self.expr.clone().field(key).into())
285    }
286
287    #[staticmethod]
288    pub fn literal(value: PyScalarValue) -> PyExpr {
289        lit(value.0).into()
290    }
291
292    #[staticmethod]
293    pub fn literal_with_metadata(
294        value: PyScalarValue,
295        metadata: HashMap<String, String>,
296    ) -> PyExpr {
297        let metadata = FieldMetadata::new(metadata.into_iter().collect());
298        lit_with_metadata(value.0, Some(metadata)).into()
299    }
300
301    #[staticmethod]
302    pub fn column(value: &str) -> PyExpr {
303        col(value).into()
304    }
305
306    /// assign a name to the PyExpr
307    #[pyo3(signature = (name, metadata=None))]
308    pub fn alias(&self, name: &str, metadata: Option<HashMap<String, String>>) -> PyExpr {
309        let metadata = metadata.map(|m| FieldMetadata::new(m.into_iter().collect()));
310        self.expr.clone().alias_with_metadata(name, metadata).into()
311    }
312
313    /// Create a sort PyExpr from an existing PyExpr.
314    #[pyo3(signature = (ascending=true, nulls_first=true))]
315    pub fn sort(&self, ascending: bool, nulls_first: bool) -> PySortExpr {
316        self.expr.clone().sort(ascending, nulls_first).into()
317    }
318
319    pub fn is_null(&self) -> PyExpr {
320        self.expr.clone().is_null().into()
321    }
322
323    pub fn is_not_null(&self) -> PyExpr {
324        self.expr.clone().is_not_null().into()
325    }
326
327    pub fn cast(&self, to: PyArrowType<DataType>) -> PyExpr {
328        // self.expr.cast_to() requires DFSchema to validate that the cast
329        // is supported, omit that for now
330        let expr = Expr::Cast(Cast::new(Box::new(self.expr.clone()), to.0));
331        expr.into()
332    }
333
334    #[pyo3(signature = (low, high, negated=false))]
335    pub fn between(&self, low: PyExpr, high: PyExpr, negated: bool) -> PyExpr {
336        let expr = Expr::Between(Between::new(
337            Box::new(self.expr.clone()),
338            negated,
339            Box::new(low.into()),
340            Box::new(high.into()),
341        ));
342        expr.into()
343    }
344
345    /// A Rex (Row Expression) specifies a single row of data. That specification
346    /// could include user defined functions or types. RexType identifies the row
347    /// as one of the possible valid `RexTypes`.
348    pub fn rex_type(&self) -> PyResult<RexType> {
349        Ok(match self.expr {
350            Expr::Alias(..) => RexType::Alias,
351            Expr::Column(..) => RexType::Reference,
352            Expr::ScalarVariable(..) | Expr::Literal(..) => RexType::Literal,
353            Expr::BinaryExpr { .. }
354            | Expr::Not(..)
355            | Expr::IsNotNull(..)
356            | Expr::Negative(..)
357            | Expr::IsNull(..)
358            | Expr::Like { .. }
359            | Expr::SimilarTo { .. }
360            | Expr::Between { .. }
361            | Expr::Case { .. }
362            | Expr::Cast { .. }
363            | Expr::TryCast { .. }
364            | Expr::ScalarFunction { .. }
365            | Expr::AggregateFunction { .. }
366            | Expr::WindowFunction { .. }
367            | Expr::InList { .. }
368            | Expr::Exists { .. }
369            | Expr::InSubquery { .. }
370            | Expr::GroupingSet(..)
371            | Expr::IsTrue(..)
372            | Expr::IsFalse(..)
373            | Expr::IsUnknown(_)
374            | Expr::IsNotTrue(..)
375            | Expr::IsNotFalse(..)
376            | Expr::Placeholder { .. }
377            | Expr::OuterReferenceColumn(_, _)
378            | Expr::Unnest(_)
379            | Expr::IsNotUnknown(_) => RexType::Call,
380            Expr::ScalarSubquery(..) => RexType::ScalarSubquery,
381            #[allow(deprecated)]
382            Expr::Wildcard { .. } => {
383                return Err(py_unsupported_variant_err("Expr::Wildcard is unsupported"));
384            }
385        })
386    }
387
388    /// Given the current `Expr` return the DataTypeMap which represents the
389    /// PythonType, Arrow DataType, and SqlType Enum which represents
390    pub fn types(&self) -> PyResult<DataTypeMap> {
391        Self::_types(&self.expr)
392    }
393
394    /// Extracts the Expr value into a Py<PyAny> that can be shared with Python
395    pub fn python_value<'py>(&self, py: Python<'py>) -> PyResult<Bound<'py, PyAny>> {
396        match &self.expr {
397            Expr::Literal(scalar_value, _) => scalar_to_pyarrow(scalar_value, py),
398            _ => Err(py_type_err(format!(
399                "Non Expr::Literal encountered in types: {:?}",
400                &self.expr
401            ))),
402        }
403    }
404
405    /// Row expressions, Rex(s), operate on the concept of operands. Different variants of Expressions, Expr(s),
406    /// store those operands in different datastructures. This function examines the Expr variant and returns
407    /// the operands to the calling logic as a Vec of PyExpr instances.
408    pub fn rex_call_operands(&self) -> PyResult<Vec<PyExpr>> {
409        match &self.expr {
410            // Expr variants that are themselves the operand to return
411            Expr::Column(..) | Expr::ScalarVariable(..) | Expr::Literal(..) => {
412                Ok(vec![PyExpr::from(self.expr.clone())])
413            }
414
415            Expr::Alias(alias) => Ok(vec![PyExpr::from(*alias.expr.clone())]),
416
417            // Expr(s) that house the Expr instance to return in their bounded params
418            Expr::Not(expr)
419            | Expr::IsNull(expr)
420            | Expr::IsNotNull(expr)
421            | Expr::IsTrue(expr)
422            | Expr::IsFalse(expr)
423            | Expr::IsUnknown(expr)
424            | Expr::IsNotTrue(expr)
425            | Expr::IsNotFalse(expr)
426            | Expr::IsNotUnknown(expr)
427            | Expr::Negative(expr)
428            | Expr::Cast(Cast { expr, .. })
429            | Expr::TryCast(TryCast { expr, .. })
430            | Expr::InSubquery(InSubquery { expr, .. }) => Ok(vec![PyExpr::from(*expr.clone())]),
431
432            // Expr variants containing a collection of Expr(s) for operands
433            Expr::AggregateFunction(AggregateFunction {
434                params: AggregateFunctionParams { args, .. },
435                ..
436            })
437            | Expr::ScalarFunction(ScalarFunction { args, .. }) => {
438                Ok(args.iter().map(|arg| PyExpr::from(arg.clone())).collect())
439            }
440            Expr::WindowFunction(boxed_window_fn) => {
441                let args = &boxed_window_fn.params.args;
442                Ok(args.iter().map(|arg| PyExpr::from(arg.clone())).collect())
443            }
444
445            // Expr(s) that require more specific processing
446            Expr::Case(Case {
447                expr,
448                when_then_expr,
449                else_expr,
450            }) => {
451                let mut operands: Vec<PyExpr> = Vec::new();
452
453                if let Some(e) = expr {
454                    for (when, then) in when_then_expr {
455                        operands.push(PyExpr::from(Expr::BinaryExpr(BinaryExpr::new(
456                            Box::new(*e.clone()),
457                            Operator::Eq,
458                            Box::new(*when.clone()),
459                        ))));
460                        operands.push(PyExpr::from(*then.clone()));
461                    }
462                } else {
463                    for (when, then) in when_then_expr {
464                        operands.push(PyExpr::from(*when.clone()));
465                        operands.push(PyExpr::from(*then.clone()));
466                    }
467                };
468
469                if let Some(e) = else_expr {
470                    operands.push(PyExpr::from(*e.clone()));
471                };
472
473                Ok(operands)
474            }
475            Expr::InList(InList { expr, list, .. }) => {
476                let mut operands: Vec<PyExpr> = vec![PyExpr::from(*expr.clone())];
477                for list_elem in list {
478                    operands.push(PyExpr::from(list_elem.clone()));
479                }
480
481                Ok(operands)
482            }
483            Expr::BinaryExpr(BinaryExpr { left, right, .. }) => Ok(vec![
484                PyExpr::from(*left.clone()),
485                PyExpr::from(*right.clone()),
486            ]),
487            Expr::Like(Like { expr, pattern, .. }) => Ok(vec![
488                PyExpr::from(*expr.clone()),
489                PyExpr::from(*pattern.clone()),
490            ]),
491            Expr::SimilarTo(Like { expr, pattern, .. }) => Ok(vec![
492                PyExpr::from(*expr.clone()),
493                PyExpr::from(*pattern.clone()),
494            ]),
495            Expr::Between(Between {
496                expr,
497                negated: _,
498                low,
499                high,
500            }) => Ok(vec![
501                PyExpr::from(*expr.clone()),
502                PyExpr::from(*low.clone()),
503                PyExpr::from(*high.clone()),
504            ]),
505
506            // Currently un-support/implemented Expr types for Rex Call operations
507            Expr::GroupingSet(..)
508            | Expr::Unnest(_)
509            | Expr::OuterReferenceColumn(_, _)
510            | Expr::ScalarSubquery(..)
511            | Expr::Placeholder { .. }
512            | Expr::Exists { .. } => Err(py_runtime_err(format!(
513                "Unimplemented Expr type: {}",
514                self.expr
515            ))),
516
517            #[allow(deprecated)]
518            Expr::Wildcard { .. } => {
519                Err(py_unsupported_variant_err("Expr::Wildcard is unsupported"))
520            }
521        }
522    }
523
524    /// Extracts the operator associated with a RexType::Call
525    pub fn rex_call_operator(&self) -> PyResult<String> {
526        Ok(match &self.expr {
527            Expr::BinaryExpr(BinaryExpr {
528                left: _,
529                op,
530                right: _,
531            }) => format!("{op}"),
532            Expr::ScalarFunction(ScalarFunction { func, args: _ }) => func.name().to_string(),
533            Expr::Cast { .. } => "cast".to_string(),
534            Expr::Between { .. } => "between".to_string(),
535            Expr::Case { .. } => "case".to_string(),
536            Expr::IsNull(..) => "is null".to_string(),
537            Expr::IsNotNull(..) => "is not null".to_string(),
538            Expr::IsTrue(_) => "is true".to_string(),
539            Expr::IsFalse(_) => "is false".to_string(),
540            Expr::IsUnknown(_) => "is unknown".to_string(),
541            Expr::IsNotTrue(_) => "is not true".to_string(),
542            Expr::IsNotFalse(_) => "is not false".to_string(),
543            Expr::IsNotUnknown(_) => "is not unknown".to_string(),
544            Expr::InList { .. } => "in list".to_string(),
545            Expr::Negative(..) => "negative".to_string(),
546            Expr::Not(..) => "not".to_string(),
547            Expr::Like(Like {
548                negated,
549                case_insensitive,
550                ..
551            }) => {
552                let name = if *case_insensitive { "ilike" } else { "like" };
553                if *negated {
554                    format!("not {name}")
555                } else {
556                    name.to_string()
557                }
558            }
559            Expr::SimilarTo(Like { negated, .. }) => {
560                if *negated {
561                    "not similar to".to_string()
562                } else {
563                    "similar to".to_string()
564                }
565            }
566            _ => {
567                return Err(py_type_err(format!(
568                    "Catch all triggered in get_operator_name: {:?}",
569                    &self.expr
570                )));
571            }
572        })
573    }
574
575    pub fn column_name(&self, plan: PyLogicalPlan) -> PyResult<String> {
576        self._column_name(&plan.plan()).map_err(py_runtime_err)
577    }
578
579    // Expression Function Builder functions
580
581    pub fn order_by(&self, order_by: Vec<PySortExpr>) -> PyExprFuncBuilder {
582        self.expr
583            .clone()
584            .order_by(to_sort_expressions(order_by))
585            .into()
586    }
587
588    pub fn filter(&self, filter: PyExpr) -> PyExprFuncBuilder {
589        self.expr.clone().filter(filter.expr.clone()).into()
590    }
591
592    pub fn distinct(&self) -> PyExprFuncBuilder {
593        self.expr.clone().distinct().into()
594    }
595
596    pub fn null_treatment(&self, null_treatment: NullTreatment) -> PyExprFuncBuilder {
597        self.expr
598            .clone()
599            .null_treatment(Some(null_treatment.into()))
600            .into()
601    }
602
603    pub fn partition_by(&self, partition_by: Vec<PyExpr>) -> PyExprFuncBuilder {
604        let partition_by = partition_by.iter().map(|e| e.expr.clone()).collect();
605        self.expr.clone().partition_by(partition_by).into()
606    }
607
608    pub fn window_frame(&self, window_frame: PyWindowFrame) -> PyExprFuncBuilder {
609        self.expr.clone().window_frame(window_frame.into()).into()
610    }
611
612    #[pyo3(signature = (partition_by=None, window_frame=None, order_by=None, null_treatment=None))]
613    pub fn over(
614        &self,
615        partition_by: Option<Vec<PyExpr>>,
616        window_frame: Option<PyWindowFrame>,
617        order_by: Option<Vec<PySortExpr>>,
618        null_treatment: Option<NullTreatment>,
619    ) -> PyDataFusionResult<PyExpr> {
620        match &self.expr {
621            Expr::AggregateFunction(agg_fn) => {
622                let window_fn = Expr::WindowFunction(Box::new(WindowFunction::new(
623                    WindowFunctionDefinition::AggregateUDF(agg_fn.func.clone()),
624                    agg_fn.params.args.clone(),
625                )));
626
627                add_builder_fns_to_window(
628                    window_fn,
629                    partition_by,
630                    window_frame,
631                    order_by,
632                    null_treatment,
633                )
634            }
635            Expr::WindowFunction(_) => add_builder_fns_to_window(
636                self.expr.clone(),
637                partition_by,
638                window_frame,
639                order_by,
640                null_treatment,
641            ),
642            _ => Err(datafusion::error::DataFusionError::Plan(format!(
643                "Using {} with `over` is not allowed. Must use an aggregate or window function.",
644                self.expr.variant_name()
645            ))
646            .into()),
647        }
648    }
649}
650
651#[pyclass(frozen, name = "ExprFuncBuilder", module = "datafusion.expr", subclass)]
652#[derive(Debug, Clone)]
653pub struct PyExprFuncBuilder {
654    pub builder: ExprFuncBuilder,
655}
656
657impl From<ExprFuncBuilder> for PyExprFuncBuilder {
658    fn from(builder: ExprFuncBuilder) -> Self {
659        Self { builder }
660    }
661}
662
663#[pymethods]
664impl PyExprFuncBuilder {
665    pub fn order_by(&self, order_by: Vec<PySortExpr>) -> PyExprFuncBuilder {
666        self.builder
667            .clone()
668            .order_by(to_sort_expressions(order_by))
669            .into()
670    }
671
672    pub fn filter(&self, filter: PyExpr) -> PyExprFuncBuilder {
673        self.builder.clone().filter(filter.expr.clone()).into()
674    }
675
676    pub fn distinct(&self) -> PyExprFuncBuilder {
677        self.builder.clone().distinct().into()
678    }
679
680    pub fn null_treatment(&self, null_treatment: NullTreatment) -> PyExprFuncBuilder {
681        self.builder
682            .clone()
683            .null_treatment(Some(null_treatment.into()))
684            .into()
685    }
686
687    pub fn partition_by(&self, partition_by: Vec<PyExpr>) -> PyExprFuncBuilder {
688        let partition_by = partition_by.iter().map(|e| e.expr.clone()).collect();
689        self.builder.clone().partition_by(partition_by).into()
690    }
691
692    pub fn window_frame(&self, window_frame: PyWindowFrame) -> PyExprFuncBuilder {
693        self.builder
694            .clone()
695            .window_frame(window_frame.into())
696            .into()
697    }
698
699    pub fn build(&self) -> PyDataFusionResult<PyExpr> {
700        Ok(self.builder.clone().build().map(|expr| expr.into())?)
701    }
702}
703
704impl PyExpr {
705    pub fn _column_name(&self, plan: &LogicalPlan) -> PyDataFusionResult<String> {
706        let field = Self::expr_to_field(&self.expr, plan)?;
707        Ok(field.name().to_owned())
708    }
709
710    /// Create a [Field] representing an [Expr], given an input [LogicalPlan] to resolve against
711    pub fn expr_to_field(expr: &Expr, input_plan: &LogicalPlan) -> PyDataFusionResult<Arc<Field>> {
712        let fields = exprlist_to_fields(std::slice::from_ref(expr), input_plan)?;
713        Ok(fields[0].1.clone())
714    }
715    fn _types(expr: &Expr) -> PyResult<DataTypeMap> {
716        match expr {
717            Expr::BinaryExpr(BinaryExpr {
718                left: _,
719                op,
720                right: _,
721            }) => match op {
722                Operator::Eq
723                | Operator::NotEq
724                | Operator::Lt
725                | Operator::LtEq
726                | Operator::Gt
727                | Operator::GtEq
728                | Operator::And
729                | Operator::Or
730                | Operator::IsDistinctFrom
731                | Operator::IsNotDistinctFrom
732                | Operator::RegexMatch
733                | Operator::RegexIMatch
734                | Operator::RegexNotMatch
735                | Operator::RegexNotIMatch
736                | Operator::LikeMatch
737                | Operator::ILikeMatch
738                | Operator::NotLikeMatch
739                | Operator::NotILikeMatch => DataTypeMap::map_from_arrow_type(&DataType::Boolean),
740                Operator::Plus | Operator::Minus | Operator::Multiply | Operator::Modulo => {
741                    DataTypeMap::map_from_arrow_type(&DataType::Int64)
742                }
743                Operator::Divide => DataTypeMap::map_from_arrow_type(&DataType::Float64),
744                Operator::StringConcat => DataTypeMap::map_from_arrow_type(&DataType::Utf8),
745                Operator::BitwiseShiftLeft
746                | Operator::BitwiseShiftRight
747                | Operator::BitwiseXor
748                | Operator::BitwiseAnd
749                | Operator::BitwiseOr => DataTypeMap::map_from_arrow_type(&DataType::Binary),
750                Operator::AtArrow
751                | Operator::ArrowAt
752                | Operator::Arrow
753                | Operator::LongArrow
754                | Operator::HashArrow
755                | Operator::HashLongArrow
756                | Operator::AtAt
757                | Operator::IntegerDivide
758                | Operator::HashMinus
759                | Operator::AtQuestion
760                | Operator::Question
761                | Operator::QuestionAnd
762                | Operator::QuestionPipe => Err(py_type_err(format!("Unsupported expr: ${op}"))),
763            },
764            Expr::Cast(Cast { expr: _, data_type }) => DataTypeMap::map_from_arrow_type(data_type),
765            Expr::Literal(scalar_value, _) => DataTypeMap::map_from_scalar_value(scalar_value),
766            _ => Err(py_type_err(format!(
767                "Non Expr::Literal encountered in types: {expr:?}"
768            ))),
769        }
770    }
771}
772
773/// Initializes the `expr` module to match the pattern of `datafusion-expr` https://docs.rs/datafusion-expr/latest/datafusion_expr/
774pub(crate) fn init_module(m: &Bound<'_, PyModule>) -> PyResult<()> {
775    m.add_class::<PyExpr>()?;
776    m.add_class::<PyColumn>()?;
777    m.add_class::<PyLiteral>()?;
778    m.add_class::<PyBinaryExpr>()?;
779    m.add_class::<PyLiteral>()?;
780    m.add_class::<PyAggregateFunction>()?;
781    m.add_class::<PyNot>()?;
782    m.add_class::<PyIsNotNull>()?;
783    m.add_class::<PyIsNull>()?;
784    m.add_class::<PyIsTrue>()?;
785    m.add_class::<PyIsFalse>()?;
786    m.add_class::<PyIsUnknown>()?;
787    m.add_class::<PyIsNotTrue>()?;
788    m.add_class::<PyIsNotFalse>()?;
789    m.add_class::<PyIsNotUnknown>()?;
790    m.add_class::<PyNegative>()?;
791    m.add_class::<PyLike>()?;
792    m.add_class::<PyILike>()?;
793    m.add_class::<PySimilarTo>()?;
794    m.add_class::<PyScalarVariable>()?;
795    m.add_class::<alias::PyAlias>()?;
796    m.add_class::<in_list::PyInList>()?;
797    m.add_class::<exists::PyExists>()?;
798    m.add_class::<subquery::PySubquery>()?;
799    m.add_class::<in_subquery::PyInSubquery>()?;
800    m.add_class::<scalar_subquery::PyScalarSubquery>()?;
801    m.add_class::<placeholder::PyPlaceholder>()?;
802    m.add_class::<grouping_set::PyGroupingSet>()?;
803    m.add_class::<case::PyCase>()?;
804    m.add_class::<conditional_expr::PyCaseBuilder>()?;
805    m.add_class::<cast::PyCast>()?;
806    m.add_class::<cast::PyTryCast>()?;
807    m.add_class::<between::PyBetween>()?;
808    m.add_class::<explain::PyExplain>()?;
809    m.add_class::<limit::PyLimit>()?;
810    m.add_class::<aggregate::PyAggregate>()?;
811    m.add_class::<sort::PySort>()?;
812    m.add_class::<analyze::PyAnalyze>()?;
813    m.add_class::<empty_relation::PyEmptyRelation>()?;
814    m.add_class::<join::PyJoin>()?;
815    m.add_class::<join::PyJoinType>()?;
816    m.add_class::<join::PyJoinConstraint>()?;
817    m.add_class::<union::PyUnion>()?;
818    m.add_class::<unnest::PyUnnest>()?;
819    m.add_class::<unnest_expr::PyUnnestExpr>()?;
820    m.add_class::<extension::PyExtension>()?;
821    m.add_class::<filter::PyFilter>()?;
822    m.add_class::<projection::PyProjection>()?;
823    m.add_class::<table_scan::PyTableScan>()?;
824    m.add_class::<create_memory_table::PyCreateMemoryTable>()?;
825    m.add_class::<create_view::PyCreateView>()?;
826    m.add_class::<distinct::PyDistinct>()?;
827    m.add_class::<sort_expr::PySortExpr>()?;
828    m.add_class::<subquery_alias::PySubqueryAlias>()?;
829    m.add_class::<drop_table::PyDropTable>()?;
830    m.add_class::<repartition::PyPartitioning>()?;
831    m.add_class::<repartition::PyRepartition>()?;
832    m.add_class::<window::PyWindowExpr>()?;
833    m.add_class::<window::PyWindowFrame>()?;
834    m.add_class::<window::PyWindowFrameBound>()?;
835    m.add_class::<copy_to::PyCopyTo>()?;
836    m.add_class::<copy_to::PyFileType>()?;
837    m.add_class::<create_catalog::PyCreateCatalog>()?;
838    m.add_class::<create_catalog_schema::PyCreateCatalogSchema>()?;
839    m.add_class::<create_external_table::PyCreateExternalTable>()?;
840    m.add_class::<create_function::PyCreateFunction>()?;
841    m.add_class::<create_function::PyOperateFunctionArg>()?;
842    m.add_class::<create_function::PyCreateFunctionBody>()?;
843    m.add_class::<create_index::PyCreateIndex>()?;
844    m.add_class::<describe_table::PyDescribeTable>()?;
845    m.add_class::<dml::PyDmlStatement>()?;
846    m.add_class::<drop_catalog_schema::PyDropCatalogSchema>()?;
847    m.add_class::<drop_function::PyDropFunction>()?;
848    m.add_class::<drop_view::PyDropView>()?;
849    m.add_class::<recursive_query::PyRecursiveQuery>()?;
850
851    m.add_class::<statement::PyTransactionStart>()?;
852    m.add_class::<statement::PyTransactionEnd>()?;
853    m.add_class::<statement::PySetVariable>()?;
854    m.add_class::<statement::PyPrepare>()?;
855    m.add_class::<statement::PyExecute>()?;
856    m.add_class::<statement::PyDeallocate>()?;
857    m.add_class::<values::PyValues>()?;
858    m.add_class::<statement::PyTransactionAccessMode>()?;
859    m.add_class::<statement::PyTransactionConclusion>()?;
860    m.add_class::<statement::PyTransactionIsolationLevel>()?;
861
862    Ok(())
863}
datafusion_python/expr.rs

datafusion_python/
expr.rs
