datafusion_sql/expr/
mod.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 arrow::datatypes::{DataType, TimeUnit};
19use datafusion_expr::planner::{
20    PlannerResult, RawBinaryExpr, RawDictionaryExpr, RawFieldAccessExpr,
21};
22use sqlparser::ast::{
23    AccessExpr, BinaryOperator, CastFormat, CastKind, DataType as SQLDataType,
24    DictionaryField, Expr as SQLExpr, ExprWithAlias as SQLExprWithAlias, MapEntry,
25    StructField, Subscript, TrimWhereField, Value,
26};
27
28use datafusion_common::{
29    internal_datafusion_err, internal_err, not_impl_err, plan_err, Column, DFSchema,
30    Result, ScalarValue,
31};
32
33use datafusion_expr::expr::ScalarFunction;
34use datafusion_expr::expr::{InList, WildcardOptions};
35use datafusion_expr::{
36    lit, Between, BinaryExpr, Cast, Expr, ExprSchemable, GetFieldAccess, Like, Literal,
37    Operator, TryCast,
38};
39
40use crate::planner::{ContextProvider, PlannerContext, SqlToRel};
41
42mod binary_op;
43mod function;
44mod grouping_set;
45mod identifier;
46mod order_by;
47mod subquery;
48mod substring;
49mod unary_op;
50mod value;
51
52impl<S: ContextProvider> SqlToRel<'_, S> {
53    pub(crate) fn sql_expr_to_logical_expr_with_alias(
54        &self,
55        sql: SQLExprWithAlias,
56        schema: &DFSchema,
57        planner_context: &mut PlannerContext,
58    ) -> Result<Expr> {
59        let mut expr =
60            self.sql_expr_to_logical_expr(sql.expr, schema, planner_context)?;
61        if let Some(alias) = sql.alias {
62            expr = expr.alias(alias.value);
63        }
64        Ok(expr)
65    }
66    pub(crate) fn sql_expr_to_logical_expr(
67        &self,
68        sql: SQLExpr,
69        schema: &DFSchema,
70        planner_context: &mut PlannerContext,
71    ) -> Result<Expr> {
72        enum StackEntry {
73            SQLExpr(Box<SQLExpr>),
74            Operator(BinaryOperator),
75        }
76
77        // Virtual stack machine to convert SQLExpr to Expr
78        // This allows visiting the expr tree in a depth-first manner which
79        // produces expressions in postfix notations, i.e. `a + b` => `a b +`.
80        // See https://github.com/apache/datafusion/issues/1444
81        let mut stack = vec![StackEntry::SQLExpr(Box::new(sql))];
82        let mut eval_stack = vec![];
83
84        while let Some(entry) = stack.pop() {
85            match entry {
86                StackEntry::SQLExpr(sql_expr) => {
87                    match *sql_expr {
88                        SQLExpr::BinaryOp { left, op, right } => {
89                            // Note the order that we push the entries to the stack
90                            // is important. We want to visit the left node first.
91                            stack.push(StackEntry::Operator(op));
92                            stack.push(StackEntry::SQLExpr(right));
93                            stack.push(StackEntry::SQLExpr(left));
94                        }
95                        _ => {
96                            let expr = self.sql_expr_to_logical_expr_internal(
97                                *sql_expr,
98                                schema,
99                                planner_context,
100                            )?;
101                            eval_stack.push(expr);
102                        }
103                    }
104                }
105                StackEntry::Operator(op) => {
106                    let right = eval_stack.pop().unwrap();
107                    let left = eval_stack.pop().unwrap();
108                    let expr = self.build_logical_expr(op, left, right, schema)?;
109                    eval_stack.push(expr);
110                }
111            }
112        }
113
114        assert_eq!(1, eval_stack.len());
115        let expr = eval_stack.pop().unwrap();
116        Ok(expr)
117    }
118
119    fn build_logical_expr(
120        &self,
121        op: BinaryOperator,
122        left: Expr,
123        right: Expr,
124        schema: &DFSchema,
125    ) -> Result<Expr> {
126        // try extension planers
127        let mut binary_expr = RawBinaryExpr { op, left, right };
128        for planner in self.context_provider.get_expr_planners() {
129            match planner.plan_binary_op(binary_expr, schema)? {
130                PlannerResult::Planned(expr) => {
131                    return Ok(expr);
132                }
133                PlannerResult::Original(expr) => {
134                    binary_expr = expr;
135                }
136            }
137        }
138
139        let RawBinaryExpr { op, left, right } = binary_expr;
140        Ok(Expr::BinaryExpr(BinaryExpr::new(
141            Box::new(left),
142            self.parse_sql_binary_op(op)?,
143            Box::new(right),
144        )))
145    }
146
147    pub fn sql_to_expr_with_alias(
148        &self,
149        sql: SQLExprWithAlias,
150        schema: &DFSchema,
151        planner_context: &mut PlannerContext,
152    ) -> Result<Expr> {
153        let mut expr =
154            self.sql_expr_to_logical_expr_with_alias(sql, schema, planner_context)?;
155        expr = self.rewrite_partial_qualifier(expr, schema);
156        self.validate_schema_satisfies_exprs(schema, &[expr.clone()])?;
157        let (expr, _) = expr.infer_placeholder_types(schema)?;
158        Ok(expr)
159    }
160
161    /// Generate a relational expression from a SQL expression
162    pub fn sql_to_expr(
163        &self,
164        sql: SQLExpr,
165        schema: &DFSchema,
166        planner_context: &mut PlannerContext,
167    ) -> Result<Expr> {
168        // The location of the original SQL expression in the source code
169        let mut expr = self.sql_expr_to_logical_expr(sql, schema, planner_context)?;
170        expr = self.rewrite_partial_qualifier(expr, schema);
171        self.validate_schema_satisfies_exprs(schema, std::slice::from_ref(&expr))?;
172        let (expr, _) = expr.infer_placeholder_types(schema)?;
173        Ok(expr)
174    }
175
176    /// Rewrite aliases which are not-complete (e.g. ones that only include only table qualifier in a schema.table qualified relation)
177    fn rewrite_partial_qualifier(&self, expr: Expr, schema: &DFSchema) -> Expr {
178        match expr {
179            Expr::Column(col) => match &col.relation {
180                Some(q) => {
181                    match schema.iter().find(|(qualifier, field)| match qualifier {
182                        Some(field_q) => {
183                            field.name() == &col.name
184                                && field_q.to_string().ends_with(&format!(".{q}"))
185                        }
186                        _ => false,
187                    }) {
188                        Some((qualifier, df_field)) => Expr::from((qualifier, df_field)),
189                        None => Expr::Column(col),
190                    }
191                }
192                None => Expr::Column(col),
193            },
194            _ => expr,
195        }
196    }
197
198    /// Internal implementation. Use
199    /// [`Self::sql_expr_to_logical_expr`] to plan exprs.
200    #[cfg_attr(feature = "recursive_protection", recursive::recursive)]
201    fn sql_expr_to_logical_expr_internal(
202        &self,
203        sql: SQLExpr,
204        schema: &DFSchema,
205        planner_context: &mut PlannerContext,
206    ) -> Result<Expr> {
207        // NOTE: This function is called recursively, so each match arm body should be as
208        //       small as possible to decrease stack requirement.
209        //       Follow the common pattern of extracting into a separate function for
210        //       non-trivial arms. See https://github.com/apache/datafusion/pull/12384 for
211        //       more context.
212        match sql {
213            SQLExpr::Value(value) => {
214                self.parse_value(value, planner_context.prepare_param_data_types())
215            }
216            SQLExpr::Extract { field, expr, .. } => {
217                let mut extract_args = vec![
218                    Expr::Literal(ScalarValue::from(format!("{field}"))),
219                    self.sql_expr_to_logical_expr(*expr, schema, planner_context)?,
220                ];
221
222                for planner in self.context_provider.get_expr_planners() {
223                    match planner.plan_extract(extract_args)? {
224                        PlannerResult::Planned(expr) => return Ok(expr),
225                        PlannerResult::Original(args) => {
226                            extract_args = args;
227                        }
228                    }
229                }
230
231                not_impl_err!("Extract not supported by ExprPlanner: {extract_args:?}")
232            }
233
234            SQLExpr::Array(arr) => self.sql_array_literal(arr.elem, schema),
235            SQLExpr::Interval(interval) => self.sql_interval_to_expr(false, interval),
236            SQLExpr::Identifier(id) => {
237                self.sql_identifier_to_expr(id, schema, planner_context)
238            }
239
240            // <expr>["foo"], <expr>[4] or <expr>[4:5]
241            SQLExpr::CompoundFieldAccess { root, access_chain } => self
242                .sql_compound_field_access_to_expr(
243                    *root,
244                    access_chain,
245                    schema,
246                    planner_context,
247                ),
248
249            SQLExpr::CompoundIdentifier(ids) => {
250                self.sql_compound_identifier_to_expr(ids, schema, planner_context)
251            }
252
253            SQLExpr::Case {
254                operand,
255                conditions,
256                results,
257                else_result,
258            } => self.sql_case_identifier_to_expr(
259                operand,
260                conditions,
261                results,
262                else_result,
263                schema,
264                planner_context,
265            ),
266
267            SQLExpr::Cast {
268                kind: CastKind::Cast | CastKind::DoubleColon,
269                expr,
270                data_type,
271                format,
272            } => self.sql_cast_to_expr(*expr, data_type, format, schema, planner_context),
273
274            SQLExpr::Cast {
275                kind: CastKind::TryCast | CastKind::SafeCast,
276                expr,
277                data_type,
278                format,
279            } => {
280                if let Some(format) = format {
281                    return not_impl_err!("CAST with format is not supported: {format}");
282                }
283
284                Ok(Expr::TryCast(TryCast::new(
285                    Box::new(self.sql_expr_to_logical_expr(
286                        *expr,
287                        schema,
288                        planner_context,
289                    )?),
290                    self.convert_data_type(&data_type)?,
291                )))
292            }
293
294            SQLExpr::TypedString { data_type, value } => Ok(Expr::Cast(Cast::new(
295                Box::new(lit(value)),
296                self.convert_data_type(&data_type)?,
297            ))),
298
299            SQLExpr::IsNull(expr) => Ok(Expr::IsNull(Box::new(
300                self.sql_expr_to_logical_expr(*expr, schema, planner_context)?,
301            ))),
302
303            SQLExpr::IsNotNull(expr) => Ok(Expr::IsNotNull(Box::new(
304                self.sql_expr_to_logical_expr(*expr, schema, planner_context)?,
305            ))),
306
307            SQLExpr::IsDistinctFrom(left, right) => {
308                Ok(Expr::BinaryExpr(BinaryExpr::new(
309                    Box::new(self.sql_expr_to_logical_expr(
310                        *left,
311                        schema,
312                        planner_context,
313                    )?),
314                    Operator::IsDistinctFrom,
315                    Box::new(self.sql_expr_to_logical_expr(
316                        *right,
317                        schema,
318                        planner_context,
319                    )?),
320                )))
321            }
322
323            SQLExpr::IsNotDistinctFrom(left, right) => {
324                Ok(Expr::BinaryExpr(BinaryExpr::new(
325                    Box::new(self.sql_expr_to_logical_expr(
326                        *left,
327                        schema,
328                        planner_context,
329                    )?),
330                    Operator::IsNotDistinctFrom,
331                    Box::new(self.sql_expr_to_logical_expr(
332                        *right,
333                        schema,
334                        planner_context,
335                    )?),
336                )))
337            }
338
339            SQLExpr::IsTrue(expr) => Ok(Expr::IsTrue(Box::new(
340                self.sql_expr_to_logical_expr(*expr, schema, planner_context)?,
341            ))),
342
343            SQLExpr::IsFalse(expr) => Ok(Expr::IsFalse(Box::new(
344                self.sql_expr_to_logical_expr(*expr, schema, planner_context)?,
345            ))),
346
347            SQLExpr::IsNotTrue(expr) => Ok(Expr::IsNotTrue(Box::new(
348                self.sql_expr_to_logical_expr(*expr, schema, planner_context)?,
349            ))),
350
351            SQLExpr::IsNotFalse(expr) => Ok(Expr::IsNotFalse(Box::new(
352                self.sql_expr_to_logical_expr(*expr, schema, planner_context)?,
353            ))),
354
355            SQLExpr::IsUnknown(expr) => Ok(Expr::IsUnknown(Box::new(
356                self.sql_expr_to_logical_expr(*expr, schema, planner_context)?,
357            ))),
358
359            SQLExpr::IsNotUnknown(expr) => Ok(Expr::IsNotUnknown(Box::new(
360                self.sql_expr_to_logical_expr(*expr, schema, planner_context)?,
361            ))),
362
363            SQLExpr::UnaryOp { op, expr } => {
364                self.parse_sql_unary_op(op, *expr, schema, planner_context)
365            }
366
367            SQLExpr::Between {
368                expr,
369                negated,
370                low,
371                high,
372            } => Ok(Expr::Between(Between::new(
373                Box::new(self.sql_expr_to_logical_expr(
374                    *expr,
375                    schema,
376                    planner_context,
377                )?),
378                negated,
379                Box::new(self.sql_expr_to_logical_expr(*low, schema, planner_context)?),
380                Box::new(self.sql_expr_to_logical_expr(
381                    *high,
382                    schema,
383                    planner_context,
384                )?),
385            ))),
386
387            SQLExpr::InList {
388                expr,
389                list,
390                negated,
391            } => self.sql_in_list_to_expr(*expr, list, negated, schema, planner_context),
392
393            SQLExpr::Like {
394                negated,
395                expr,
396                pattern,
397                escape_char,
398                any,
399            } => self.sql_like_to_expr(
400                negated,
401                *expr,
402                *pattern,
403                escape_char,
404                schema,
405                planner_context,
406                false,
407                any,
408            ),
409
410            SQLExpr::ILike {
411                negated,
412                expr,
413                pattern,
414                escape_char,
415                any,
416            } => self.sql_like_to_expr(
417                negated,
418                *expr,
419                *pattern,
420                escape_char,
421                schema,
422                planner_context,
423                true,
424                any,
425            ),
426
427            SQLExpr::SimilarTo {
428                negated,
429                expr,
430                pattern,
431                escape_char,
432            } => self.sql_similarto_to_expr(
433                negated,
434                *expr,
435                *pattern,
436                escape_char,
437                schema,
438                planner_context,
439            ),
440
441            SQLExpr::BinaryOp { .. } => {
442                internal_err!("binary_op should be handled by sql_expr_to_logical_expr.")
443            }
444
445            #[cfg(feature = "unicode_expressions")]
446            SQLExpr::Substring {
447                expr,
448                substring_from,
449                substring_for,
450                special: _,
451            } => self.sql_substring_to_expr(
452                expr,
453                substring_from,
454                substring_for,
455                schema,
456                planner_context,
457            ),
458
459            #[cfg(not(feature = "unicode_expressions"))]
460            SQLExpr::Substring { .. } => {
461                internal_err!(
462                    "statement substring requires compilation with feature flag: unicode_expressions."
463                )
464            }
465
466            SQLExpr::Trim {
467                expr,
468                trim_where,
469                trim_what,
470                trim_characters,
471            } => self.sql_trim_to_expr(
472                *expr,
473                trim_where,
474                trim_what,
475                trim_characters,
476                schema,
477                planner_context,
478            ),
479
480            SQLExpr::Function(function) => {
481                self.sql_function_to_expr(function, schema, planner_context)
482            }
483
484            SQLExpr::Rollup(exprs) => {
485                self.sql_rollup_to_expr(exprs, schema, planner_context)
486            }
487            SQLExpr::Cube(exprs) => self.sql_cube_to_expr(exprs, schema, planner_context),
488            SQLExpr::GroupingSets(exprs) => {
489                self.sql_grouping_sets_to_expr(exprs, schema, planner_context)
490            }
491
492            SQLExpr::Floor {
493                expr,
494                field: _field,
495            } => self.sql_fn_name_to_expr(*expr, "floor", schema, planner_context),
496            SQLExpr::Ceil {
497                expr,
498                field: _field,
499            } => self.sql_fn_name_to_expr(*expr, "ceil", schema, planner_context),
500            SQLExpr::Overlay {
501                expr,
502                overlay_what,
503                overlay_from,
504                overlay_for,
505            } => self.sql_overlay_to_expr(
506                *expr,
507                *overlay_what,
508                *overlay_from,
509                overlay_for,
510                schema,
511                planner_context,
512            ),
513            SQLExpr::Nested(e) => {
514                self.sql_expr_to_logical_expr(*e, schema, planner_context)
515            }
516
517            SQLExpr::Exists { subquery, negated } => {
518                self.parse_exists_subquery(*subquery, negated, schema, planner_context)
519            }
520            SQLExpr::InSubquery {
521                expr,
522                subquery,
523                negated,
524            } => {
525                self.parse_in_subquery(*expr, *subquery, negated, schema, planner_context)
526            }
527            SQLExpr::Subquery(subquery) => {
528                self.parse_scalar_subquery(*subquery, schema, planner_context)
529            }
530
531            SQLExpr::Struct { values, fields } => {
532                self.parse_struct(schema, planner_context, values, fields)
533            }
534            SQLExpr::Position { expr, r#in } => {
535                self.sql_position_to_expr(*expr, *r#in, schema, planner_context)
536            }
537            SQLExpr::AtTimeZone {
538                timestamp,
539                time_zone,
540            } => Ok(Expr::Cast(Cast::new(
541                Box::new(self.sql_expr_to_logical_expr_internal(
542                    *timestamp,
543                    schema,
544                    planner_context,
545                )?),
546                match *time_zone {
547                    SQLExpr::Value(Value::SingleQuotedString(s)) => {
548                        DataType::Timestamp(TimeUnit::Nanosecond, Some(s.into()))
549                    }
550                    _ => {
551                        return not_impl_err!(
552                            "Unsupported ast node in sqltorel: {time_zone:?}"
553                        )
554                    }
555                },
556            ))),
557            SQLExpr::Dictionary(fields) => {
558                self.try_plan_dictionary_literal(fields, schema, planner_context)
559            }
560            SQLExpr::Map(map) => {
561                self.try_plan_map_literal(map.entries, schema, planner_context)
562            }
563            SQLExpr::AnyOp {
564                left,
565                compare_op,
566                right,
567                // ANY/SOME are equivalent, this field specifies which the user
568                // specified but it doesn't affect the plan so ignore the field
569                is_some: _,
570            } => {
571                let mut binary_expr = RawBinaryExpr {
572                    op: compare_op,
573                    left: self.sql_expr_to_logical_expr(
574                        *left,
575                        schema,
576                        planner_context,
577                    )?,
578                    right: self.sql_expr_to_logical_expr(
579                        *right,
580                        schema,
581                        planner_context,
582                    )?,
583                };
584                for planner in self.context_provider.get_expr_planners() {
585                    match planner.plan_any(binary_expr)? {
586                        PlannerResult::Planned(expr) => {
587                            return Ok(expr);
588                        }
589                        PlannerResult::Original(expr) => {
590                            binary_expr = expr;
591                        }
592                    }
593                }
594                not_impl_err!("AnyOp not supported by ExprPlanner: {binary_expr:?}")
595            }
596            #[expect(deprecated)]
597            SQLExpr::Wildcard(_token) => Ok(Expr::Wildcard {
598                qualifier: None,
599                options: Box::new(WildcardOptions::default()),
600            }),
601            #[expect(deprecated)]
602            SQLExpr::QualifiedWildcard(object_name, _token) => Ok(Expr::Wildcard {
603                qualifier: Some(self.object_name_to_table_reference(object_name)?),
604                options: Box::new(WildcardOptions::default()),
605            }),
606            SQLExpr::Tuple(values) => self.parse_tuple(schema, planner_context, values),
607            _ => not_impl_err!("Unsupported ast node in sqltorel: {sql:?}"),
608        }
609    }
610
611    /// Parses a struct(..) expression and plans it creation
612    fn parse_struct(
613        &self,
614        schema: &DFSchema,
615        planner_context: &mut PlannerContext,
616        values: Vec<SQLExpr>,
617        fields: Vec<StructField>,
618    ) -> Result<Expr> {
619        if !fields.is_empty() {
620            return not_impl_err!("Struct fields are not supported yet");
621        }
622        let is_named_struct = values
623            .iter()
624            .any(|value| matches!(value, SQLExpr::Named { .. }));
625
626        let mut create_struct_args = if is_named_struct {
627            self.create_named_struct_expr(values, schema, planner_context)?
628        } else {
629            self.create_struct_expr(values, schema, planner_context)?
630        };
631
632        for planner in self.context_provider.get_expr_planners() {
633            match planner.plan_struct_literal(create_struct_args, is_named_struct)? {
634                PlannerResult::Planned(expr) => return Ok(expr),
635                PlannerResult::Original(args) => create_struct_args = args,
636            }
637        }
638        not_impl_err!("Struct not supported by ExprPlanner: {create_struct_args:?}")
639    }
640
641    fn parse_tuple(
642        &self,
643        schema: &DFSchema,
644        planner_context: &mut PlannerContext,
645        values: Vec<SQLExpr>,
646    ) -> Result<Expr> {
647        match values.first() {
648            Some(SQLExpr::Identifier(_)) | Some(SQLExpr::Value(_)) => {
649                self.parse_struct(schema, planner_context, values, vec![])
650            }
651            None => not_impl_err!("Empty tuple not supported yet"),
652            _ => {
653                not_impl_err!("Only identifiers and literals are supported in tuples")
654            }
655        }
656    }
657
658    fn sql_position_to_expr(
659        &self,
660        substr_expr: SQLExpr,
661        str_expr: SQLExpr,
662        schema: &DFSchema,
663        planner_context: &mut PlannerContext,
664    ) -> Result<Expr> {
665        let substr =
666            self.sql_expr_to_logical_expr(substr_expr, schema, planner_context)?;
667        let fullstr = self.sql_expr_to_logical_expr(str_expr, schema, planner_context)?;
668        let mut position_args = vec![fullstr, substr];
669        for planner in self.context_provider.get_expr_planners() {
670            match planner.plan_position(position_args)? {
671                PlannerResult::Planned(expr) => return Ok(expr),
672                PlannerResult::Original(args) => {
673                    position_args = args;
674                }
675            }
676        }
677
678        not_impl_err!("Position not supported by ExprPlanner: {position_args:?}")
679    }
680
681    fn try_plan_dictionary_literal(
682        &self,
683        fields: Vec<DictionaryField>,
684        schema: &DFSchema,
685        planner_context: &mut PlannerContext,
686    ) -> Result<Expr> {
687        let mut keys = vec![];
688        let mut values = vec![];
689        for field in fields {
690            let key = lit(field.key.value);
691            let value =
692                self.sql_expr_to_logical_expr(*field.value, schema, planner_context)?;
693            keys.push(key);
694            values.push(value);
695        }
696
697        let mut raw_expr = RawDictionaryExpr { keys, values };
698
699        for planner in self.context_provider.get_expr_planners() {
700            match planner.plan_dictionary_literal(raw_expr, schema)? {
701                PlannerResult::Planned(expr) => {
702                    return Ok(expr);
703                }
704                PlannerResult::Original(expr) => raw_expr = expr,
705            }
706        }
707        not_impl_err!("Dictionary not supported by ExprPlanner: {raw_expr:?}")
708    }
709
710    fn try_plan_map_literal(
711        &self,
712        entries: Vec<MapEntry>,
713        schema: &DFSchema,
714        planner_context: &mut PlannerContext,
715    ) -> Result<Expr> {
716        let mut exprs: Vec<_> = entries
717            .into_iter()
718            .flat_map(|entry| vec![entry.key, entry.value].into_iter())
719            .map(|expr| self.sql_expr_to_logical_expr(*expr, schema, planner_context))
720            .collect::<Result<Vec<_>>>()?;
721        for planner in self.context_provider.get_expr_planners() {
722            match planner.plan_make_map(exprs)? {
723                PlannerResult::Planned(expr) => {
724                    return Ok(expr);
725                }
726                PlannerResult::Original(expr) => exprs = expr,
727            }
728        }
729        not_impl_err!("MAP not supported by ExprPlanner: {exprs:?}")
730    }
731
732    // Handles a call to struct(...) where the arguments are named. For example
733    // `struct (v as foo, v2 as bar)` by creating a call to the `named_struct` function
734    fn create_named_struct_expr(
735        &self,
736        values: Vec<SQLExpr>,
737        input_schema: &DFSchema,
738        planner_context: &mut PlannerContext,
739    ) -> Result<Vec<Expr>> {
740        Ok(values
741            .into_iter()
742            .enumerate()
743            .map(|(i, value)| {
744                let args = if let SQLExpr::Named { expr, name } = value {
745                    [
746                        name.value.lit(),
747                        self.sql_expr_to_logical_expr(
748                            *expr,
749                            input_schema,
750                            planner_context,
751                        )?,
752                    ]
753                } else {
754                    [
755                        format!("c{i}").lit(),
756                        self.sql_expr_to_logical_expr(
757                            value,
758                            input_schema,
759                            planner_context,
760                        )?,
761                    ]
762                };
763
764                Ok(args)
765            })
766            .collect::<Result<Vec<_>>>()?
767            .into_iter()
768            .flatten()
769            .collect())
770    }
771
772    // Handles a call to struct(...) where the arguments are not named. For example
773    // `struct (v, v2)` by creating a call to the `struct` function
774    // which will create a struct with fields named `c0`, `c1`, etc.
775    fn create_struct_expr(
776        &self,
777        values: Vec<SQLExpr>,
778        input_schema: &DFSchema,
779        planner_context: &mut PlannerContext,
780    ) -> Result<Vec<Expr>> {
781        values
782            .into_iter()
783            .map(|value| {
784                self.sql_expr_to_logical_expr(value, input_schema, planner_context)
785            })
786            .collect::<Result<Vec<_>>>()
787    }
788
789    fn sql_in_list_to_expr(
790        &self,
791        expr: SQLExpr,
792        list: Vec<SQLExpr>,
793        negated: bool,
794        schema: &DFSchema,
795        planner_context: &mut PlannerContext,
796    ) -> Result<Expr> {
797        let list_expr = list
798            .into_iter()
799            .map(|e| self.sql_expr_to_logical_expr(e, schema, planner_context))
800            .collect::<Result<Vec<_>>>()?;
801
802        Ok(Expr::InList(InList::new(
803            Box::new(self.sql_expr_to_logical_expr(expr, schema, planner_context)?),
804            list_expr,
805            negated,
806        )))
807    }
808
809    #[allow(clippy::too_many_arguments)]
810    fn sql_like_to_expr(
811        &self,
812        negated: bool,
813        expr: SQLExpr,
814        pattern: SQLExpr,
815        escape_char: Option<String>,
816        schema: &DFSchema,
817        planner_context: &mut PlannerContext,
818        case_insensitive: bool,
819        any: bool,
820    ) -> Result<Expr> {
821        if any {
822            return not_impl_err!("ANY in LIKE expression");
823        }
824        let pattern = self.sql_expr_to_logical_expr(pattern, schema, planner_context)?;
825        let escape_char = if let Some(char) = escape_char {
826            if char.len() != 1 {
827                return plan_err!("Invalid escape character in LIKE expression");
828            }
829            Some(char.chars().next().unwrap())
830        } else {
831            None
832        };
833        Ok(Expr::Like(Like::new(
834            negated,
835            Box::new(self.sql_expr_to_logical_expr(expr, schema, planner_context)?),
836            Box::new(pattern),
837            escape_char,
838            case_insensitive,
839        )))
840    }
841
842    fn sql_similarto_to_expr(
843        &self,
844        negated: bool,
845        expr: SQLExpr,
846        pattern: SQLExpr,
847        escape_char: Option<String>,
848        schema: &DFSchema,
849        planner_context: &mut PlannerContext,
850    ) -> Result<Expr> {
851        let pattern = self.sql_expr_to_logical_expr(pattern, schema, planner_context)?;
852        let pattern_type = pattern.get_type(schema)?;
853        if pattern_type != DataType::Utf8 && pattern_type != DataType::Null {
854            return plan_err!("Invalid pattern in SIMILAR TO expression");
855        }
856        let escape_char = if let Some(char) = escape_char {
857            if char.len() != 1 {
858                return plan_err!("Invalid escape character in SIMILAR TO expression");
859            }
860            Some(char.chars().next().unwrap())
861        } else {
862            None
863        };
864        Ok(Expr::SimilarTo(Like::new(
865            negated,
866            Box::new(self.sql_expr_to_logical_expr(expr, schema, planner_context)?),
867            Box::new(pattern),
868            escape_char,
869            false,
870        )))
871    }
872
873    fn sql_trim_to_expr(
874        &self,
875        expr: SQLExpr,
876        trim_where: Option<TrimWhereField>,
877        trim_what: Option<Box<SQLExpr>>,
878        trim_characters: Option<Vec<SQLExpr>>,
879        schema: &DFSchema,
880        planner_context: &mut PlannerContext,
881    ) -> Result<Expr> {
882        let arg = self.sql_expr_to_logical_expr(expr, schema, planner_context)?;
883        let args = match (trim_what, trim_characters) {
884            (Some(to_trim), None) => {
885                let to_trim =
886                    self.sql_expr_to_logical_expr(*to_trim, schema, planner_context)?;
887                Ok(vec![arg, to_trim])
888            }
889            (None, Some(trim_characters)) => {
890                if let Some(first) = trim_characters.first() {
891                    let to_trim = self.sql_expr_to_logical_expr(
892                        first.clone(),
893                        schema,
894                        planner_context,
895                    )?;
896                    Ok(vec![arg, to_trim])
897                } else {
898                    plan_err!("TRIM CHARACTERS cannot be empty")
899                }
900            }
901            (Some(_), Some(_)) => {
902                plan_err!("Both TRIM and TRIM CHARACTERS cannot be specified")
903            }
904            (None, None) => Ok(vec![arg]),
905        }?;
906
907        let fun_name = match trim_where {
908            Some(TrimWhereField::Leading) => "ltrim",
909            Some(TrimWhereField::Trailing) => "rtrim",
910            Some(TrimWhereField::Both) => "btrim",
911            None => "trim",
912        };
913        let fun = self
914            .context_provider
915            .get_function_meta(fun_name)
916            .ok_or_else(|| {
917                internal_datafusion_err!("Unable to find expected '{fun_name}' function")
918            })?;
919
920        Ok(Expr::ScalarFunction(ScalarFunction::new_udf(fun, args)))
921    }
922
923    fn sql_overlay_to_expr(
924        &self,
925        expr: SQLExpr,
926        overlay_what: SQLExpr,
927        overlay_from: SQLExpr,
928        overlay_for: Option<Box<SQLExpr>>,
929        schema: &DFSchema,
930        planner_context: &mut PlannerContext,
931    ) -> Result<Expr> {
932        let arg = self.sql_expr_to_logical_expr(expr, schema, planner_context)?;
933        let what_arg =
934            self.sql_expr_to_logical_expr(overlay_what, schema, planner_context)?;
935        let from_arg =
936            self.sql_expr_to_logical_expr(overlay_from, schema, planner_context)?;
937        let mut overlay_args = match overlay_for {
938            Some(for_expr) => {
939                let for_expr =
940                    self.sql_expr_to_logical_expr(*for_expr, schema, planner_context)?;
941                vec![arg, what_arg, from_arg, for_expr]
942            }
943            None => vec![arg, what_arg, from_arg],
944        };
945        for planner in self.context_provider.get_expr_planners() {
946            match planner.plan_overlay(overlay_args)? {
947                PlannerResult::Planned(expr) => return Ok(expr),
948                PlannerResult::Original(args) => overlay_args = args,
949            }
950        }
951        not_impl_err!("Overlay not supported by ExprPlanner: {overlay_args:?}")
952    }
953
954    fn sql_cast_to_expr(
955        &self,
956        expr: SQLExpr,
957        data_type: SQLDataType,
958        format: Option<CastFormat>,
959        schema: &DFSchema,
960        planner_context: &mut PlannerContext,
961    ) -> Result<Expr> {
962        if let Some(format) = format {
963            return not_impl_err!("CAST with format is not supported: {format}");
964        }
965
966        let dt = self.convert_data_type(&data_type)?;
967        let expr = self.sql_expr_to_logical_expr(expr, schema, planner_context)?;
968
969        // numeric constants are treated as seconds (rather as nanoseconds)
970        // to align with postgres / duckdb semantics
971        let expr = match &dt {
972            DataType::Timestamp(TimeUnit::Nanosecond, tz)
973                if expr.get_type(schema)? == DataType::Int64 =>
974            {
975                Expr::Cast(Cast::new(
976                    Box::new(expr),
977                    DataType::Timestamp(TimeUnit::Second, tz.clone()),
978                ))
979            }
980            _ => expr,
981        };
982
983        Ok(Expr::Cast(Cast::new(Box::new(expr), dt)))
984    }
985
986    fn sql_compound_field_access_to_expr(
987        &self,
988        root: SQLExpr,
989        access_chain: Vec<AccessExpr>,
990        schema: &DFSchema,
991        planner_context: &mut PlannerContext,
992    ) -> Result<Expr> {
993        let mut root = self.sql_expr_to_logical_expr(root, schema, planner_context)?;
994        let fields = access_chain
995            .into_iter()
996            .map(|field| match field {
997                AccessExpr::Subscript(subscript) => {
998                    match subscript {
999                        Subscript::Index { index } => {
1000                            // index can be a name, in which case it is a named field access
1001                            match index {
1002                                SQLExpr::Value(
1003                                    Value::SingleQuotedString(s)
1004                                    | Value::DoubleQuotedString(s),
1005                                ) => Ok(Some(GetFieldAccess::NamedStructField {
1006                                    name: ScalarValue::from(s),
1007                                })),
1008                                SQLExpr::JsonAccess { .. } => {
1009                                    not_impl_err!("JsonAccess")
1010                                }
1011                                // otherwise treat like a list index
1012                                _ => Ok(Some(GetFieldAccess::ListIndex {
1013                                    key: Box::new(self.sql_expr_to_logical_expr(
1014                                        index,
1015                                        schema,
1016                                        planner_context,
1017                                    )?),
1018                                })),
1019                            }
1020                        }
1021                        Subscript::Slice {
1022                            lower_bound,
1023                            upper_bound,
1024                            stride,
1025                        } => {
1026                            // Means access like [:2]
1027                            let lower_bound = if let Some(lower_bound) = lower_bound {
1028                                self.sql_expr_to_logical_expr(
1029                                    lower_bound,
1030                                    schema,
1031                                    planner_context,
1032                                )
1033                            } else {
1034                                not_impl_err!("Slice subscript requires a lower bound")
1035                            }?;
1036
1037                            // means access like [2:]
1038                            let upper_bound = if let Some(upper_bound) = upper_bound {
1039                                self.sql_expr_to_logical_expr(
1040                                    upper_bound,
1041                                    schema,
1042                                    planner_context,
1043                                )
1044                            } else {
1045                                not_impl_err!("Slice subscript requires an upper bound")
1046                            }?;
1047
1048                            // stride, default to 1
1049                            let stride = if let Some(stride) = stride {
1050                                self.sql_expr_to_logical_expr(
1051                                    stride,
1052                                    schema,
1053                                    planner_context,
1054                                )?
1055                            } else {
1056                                lit(1i64)
1057                            };
1058
1059                            Ok(Some(GetFieldAccess::ListRange {
1060                                start: Box::new(lower_bound),
1061                                stop: Box::new(upper_bound),
1062                                stride: Box::new(stride),
1063                            }))
1064                        }
1065                    }
1066                }
1067                AccessExpr::Dot(expr) => {
1068                    let expr =
1069                        self.sql_expr_to_logical_expr(expr, schema, planner_context)?;
1070                    match expr {
1071                        Expr::Column(Column {
1072                            name,
1073                            relation,
1074                            spans,
1075                        }) => {
1076                            if let Some(relation) = &relation {
1077                                // If the first part of the dot access is a column reference, we should
1078                                // check if the column is from the same table as the root expression.
1079                                // If it is, we should replace the root expression with the column reference.
1080                                // Otherwise, we should treat the dot access as a named field access.
1081                                if relation.table() == root.schema_name().to_string() {
1082                                    root = Expr::Column(Column {
1083                                        name,
1084                                        relation: Some(relation.clone()),
1085                                        spans,
1086                                    });
1087                                    Ok(None)
1088                                } else {
1089                                    plan_err!(
1090                                        "table name mismatch: {} != {}",
1091                                        relation.table(),
1092                                        root.schema_name()
1093                                    )
1094                                }
1095                            } else {
1096                                Ok(Some(GetFieldAccess::NamedStructField {
1097                                    name: ScalarValue::from(name),
1098                                }))
1099                            }
1100                        }
1101                        _ => not_impl_err!(
1102                            "Dot access not supported for non-column expr: {expr:?}"
1103                        ),
1104                    }
1105                }
1106            })
1107            .collect::<Result<Vec<_>>>()?;
1108
1109        fields
1110            .into_iter()
1111            .flatten()
1112            .try_fold(root, |expr, field_access| {
1113                let mut field_access_expr = RawFieldAccessExpr { expr, field_access };
1114                for planner in self.context_provider.get_expr_planners() {
1115                    match planner.plan_field_access(field_access_expr, schema)? {
1116                        PlannerResult::Planned(expr) => return Ok(expr),
1117                        PlannerResult::Original(expr) => {
1118                            field_access_expr = expr;
1119                        }
1120                    }
1121                }
1122                not_impl_err!(
1123                    "GetFieldAccess not supported by ExprPlanner: {field_access_expr:?}"
1124                )
1125            })
1126    }
1127}
1128
1129#[cfg(test)]
1130mod tests {
1131    use std::collections::HashMap;
1132    use std::sync::Arc;
1133
1134    use arrow::datatypes::{Field, Schema};
1135    use sqlparser::dialect::GenericDialect;
1136    use sqlparser::parser::Parser;
1137
1138    use datafusion_common::config::ConfigOptions;
1139    use datafusion_common::TableReference;
1140    use datafusion_expr::logical_plan::builder::LogicalTableSource;
1141    use datafusion_expr::{AggregateUDF, ScalarUDF, TableSource, WindowUDF};
1142
1143    use super::*;
1144
1145    struct TestContextProvider {
1146        options: ConfigOptions,
1147        tables: HashMap<String, Arc<dyn TableSource>>,
1148    }
1149
1150    impl TestContextProvider {
1151        pub fn new() -> Self {
1152            let mut tables = HashMap::new();
1153            tables.insert(
1154                "table1".to_string(),
1155                create_table_source(vec![Field::new(
1156                    "column1".to_string(),
1157                    DataType::Utf8,
1158                    false,
1159                )]),
1160            );
1161
1162            Self {
1163                options: Default::default(),
1164                tables,
1165            }
1166        }
1167    }
1168
1169    impl ContextProvider for TestContextProvider {
1170        fn get_table_source(&self, name: TableReference) -> Result<Arc<dyn TableSource>> {
1171            match self.tables.get(name.table()) {
1172                Some(table) => Ok(Arc::clone(table)),
1173                _ => plan_err!("Table not found: {}", name.table()),
1174            }
1175        }
1176
1177        fn get_function_meta(&self, _name: &str) -> Option<Arc<ScalarUDF>> {
1178            None
1179        }
1180
1181        fn get_aggregate_meta(&self, name: &str) -> Option<Arc<AggregateUDF>> {
1182            match name {
1183                "sum" => Some(datafusion_functions_aggregate::sum::sum_udaf()),
1184                _ => None,
1185            }
1186        }
1187
1188        fn get_variable_type(&self, _variable_names: &[String]) -> Option<DataType> {
1189            None
1190        }
1191
1192        fn options(&self) -> &ConfigOptions {
1193            &self.options
1194        }
1195
1196        fn get_window_meta(&self, _name: &str) -> Option<Arc<WindowUDF>> {
1197            None
1198        }
1199
1200        fn udf_names(&self) -> Vec<String> {
1201            Vec::new()
1202        }
1203
1204        fn udaf_names(&self) -> Vec<String> {
1205            vec!["sum".to_string()]
1206        }
1207
1208        fn udwf_names(&self) -> Vec<String> {
1209            Vec::new()
1210        }
1211    }
1212
1213    fn create_table_source(fields: Vec<Field>) -> Arc<dyn TableSource> {
1214        Arc::new(LogicalTableSource::new(Arc::new(
1215            Schema::new_with_metadata(fields, HashMap::new()),
1216        )))
1217    }
1218
1219    macro_rules! test_stack_overflow {
1220        ($num_expr:expr) => {
1221            paste::item! {
1222                #[test]
1223                fn [<test_stack_overflow_ $num_expr>]() {
1224                    let schema = DFSchema::empty();
1225                    let mut planner_context = PlannerContext::default();
1226
1227                    let expr_str = (0..$num_expr)
1228                        .map(|i| format!("column1 = 'value{:?}'", i))
1229                        .collect::<Vec<String>>()
1230                        .join(" OR ");
1231
1232                    let dialect = GenericDialect{};
1233                    let mut parser = Parser::new(&dialect)
1234                        .try_with_sql(expr_str.as_str())
1235                        .unwrap();
1236                    let sql_expr = parser.parse_expr().unwrap();
1237
1238                    let context_provider = TestContextProvider::new();
1239                    let sql_to_rel = SqlToRel::new(&context_provider);
1240
1241                    // Should not stack overflow
1242                    sql_to_rel.sql_expr_to_logical_expr(
1243                        sql_expr,
1244                        &schema,
1245                        &mut planner_context,
1246                    ).unwrap();
1247                }
1248            }
1249        };
1250    }
1251
1252    test_stack_overflow!(64);
1253    test_stack_overflow!(128);
1254    test_stack_overflow!(256);
1255    test_stack_overflow!(512);
1256    test_stack_overflow!(1024);
1257    test_stack_overflow!(2048);
1258    test_stack_overflow!(4096);
1259    test_stack_overflow!(8192);
1260    #[test]
1261    fn test_sql_to_expr_with_alias() {
1262        let schema = DFSchema::empty();
1263        let mut planner_context = PlannerContext::default();
1264
1265        let expr_str = "SUM(int_col) as sum_int_col";
1266
1267        let dialect = GenericDialect {};
1268        let mut parser = Parser::new(&dialect).try_with_sql(expr_str).unwrap();
1269        // from sqlparser
1270        let sql_expr = parser.parse_expr_with_alias().unwrap();
1271
1272        let context_provider = TestContextProvider::new();
1273        let sql_to_rel = SqlToRel::new(&context_provider);
1274
1275        let expr = sql_to_rel
1276            .sql_expr_to_logical_expr_with_alias(sql_expr, &schema, &mut planner_context)
1277            .unwrap();
1278
1279        assert!(matches!(expr, Expr::Alias(_)));
1280    }
1281}
datafusion_sql/expr/mod.rs

datafusion_sql/expr/
mod.rs
