vortex_expr/
lib.rs

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
use std::any::Any;
use std::fmt::{Debug, Display};
use std::sync::Arc;

use dyn_hash::DynHash;

mod binary;
mod column;
pub mod datafusion;
pub mod forms;
mod get_item;
mod identity;
mod like;
mod literal;
mod not;
mod operators;
mod pack;
mod project;
pub mod pruning;
mod row_filter;
mod select;
#[allow(dead_code)]
mod traversal;

pub use binary::*;
pub use column::*;
pub use get_item::*;
pub use identity::*;
pub use like::*;
pub use literal::*;
pub use not::*;
pub use operators::*;
pub use pack::*;
pub use project::*;
pub use row_filter::*;
pub use select::*;
use vortex_array::aliases::hash_set::HashSet;
use vortex_array::ArrayData;
use vortex_dtype::Field;
use vortex_error::{VortexResult, VortexUnwrap};

use crate::traversal::{Node, ReferenceCollector};

pub type ExprRef = Arc<dyn VortexExpr>;

/// Represents logical operation on [`ArrayData`]s
pub trait VortexExpr: Debug + Send + Sync + DynEq + DynHash + Display {
    /// Convert expression reference to reference of [`Any`] type
    fn as_any(&self) -> &dyn Any;

    /// Compute result of expression on given batch producing a new batch
    fn evaluate(&self, batch: &ArrayData) -> VortexResult<ArrayData>;

    fn children(&self) -> Vec<&ExprRef>;

    fn replacing_children(self: Arc<Self>, children: Vec<ExprRef>) -> ExprRef;
}

pub trait VortexExprExt {
    /// Accumulate all field references from this expression and its children in a set
    fn references(&self) -> HashSet<&Field>;
}

impl VortexExprExt for ExprRef {
    fn references(&self) -> HashSet<&Field> {
        let mut collector = ReferenceCollector::new();
        // The collector is infallible, so we can unwrap the result
        self.accept(&mut collector).vortex_unwrap();
        collector.into_fields()
    }
}

/// Splits top level and operations into separate expressions
pub fn split_conjunction(expr: &ExprRef) -> Vec<ExprRef> {
    let mut conjunctions = vec![];
    split_inner(expr, &mut conjunctions);
    conjunctions
}

fn split_inner(expr: &ExprRef, exprs: &mut Vec<ExprRef>) {
    match expr.as_any().downcast_ref::<BinaryExpr>() {
        Some(bexp) if bexp.op() == Operator::And => {
            split_inner(bexp.lhs(), exprs);
            split_inner(bexp.rhs(), exprs);
        }
        Some(_) | None => {
            exprs.push(expr.clone());
        }
    }
}

// Adapted from apache/datafusion https://github.com/apache/datafusion/blob/f31ca5b927c040ce03f6a3c8c8dc3d7f4ef5be34/datafusion/physical-expr-common/src/physical_expr.rs#L156
/// [`VortexExpr`] can't be constrained by [`Eq`] directly because it must remain object
/// safe. To ease implementation blanket implementation is provided for [`Eq`] types.
pub trait DynEq {
    fn dyn_eq(&self, other: &dyn Any) -> bool;
}

impl<T: Eq + Any> DynEq for T {
    fn dyn_eq(&self, other: &dyn Any) -> bool {
        other.downcast_ref::<Self>() == Some(self)
    }
}

impl PartialEq for dyn VortexExpr {
    fn eq(&self, other: &Self) -> bool {
        self.dyn_eq(other.as_any())
    }
}

impl Eq for dyn VortexExpr {}

dyn_hash::hash_trait_object!(VortexExpr);

#[cfg(test)]
mod tests {
    use vortex_dtype::{DType, Field, Nullability, PType, StructDType};
    use vortex_scalar::Scalar;

    use super::*;

    #[test]
    fn basic_expr_split_test() {
        let lhs = col("a");
        let rhs = lit(1);
        let expr = eq(lhs, rhs);
        let conjunction = split_conjunction(&expr);
        assert_eq!(conjunction.len(), 1);
    }

    #[test]
    fn basic_conjunction_split_test() {
        let lhs = col("a");
        let rhs = lit(1);
        let expr = and(lhs, rhs);
        let conjunction = split_conjunction(&expr);
        assert_eq!(conjunction.len(), 2, "Conjunction is {conjunction:?}");
    }

    #[test]
    fn expr_display() {
        assert_eq!(col("a").to_string(), "$a");
        assert_eq!(col(1).to_string(), "[1]");
        assert_eq!(Identity.to_string(), "[]");
        assert_eq!(Identity.to_string(), "[]");

        let col1: Arc<dyn VortexExpr> = col("col1");
        let col2: Arc<dyn VortexExpr> = col("col2");
        assert_eq!(
            and(col1.clone(), col2.clone()).to_string(),
            "($col1 and $col2)"
        );
        assert_eq!(
            or(col1.clone(), col2.clone()).to_string(),
            "($col1 or $col2)"
        );
        assert_eq!(
            eq(col1.clone(), col2.clone()).to_string(),
            "($col1 = $col2)"
        );
        assert_eq!(
            not_eq(col1.clone(), col2.clone()).to_string(),
            "($col1 != $col2)"
        );
        assert_eq!(
            gt(col1.clone(), col2.clone()).to_string(),
            "($col1 > $col2)"
        );
        assert_eq!(
            gt_eq(col1.clone(), col2.clone()).to_string(),
            "($col1 >= $col2)"
        );
        assert_eq!(
            lt(col1.clone(), col2.clone()).to_string(),
            "($col1 < $col2)"
        );
        assert_eq!(
            lt_eq(col1.clone(), col2.clone()).to_string(),
            "($col1 <= $col2)"
        );

        assert_eq!(
            or(
                lt(col1.clone(), col2.clone()),
                not_eq(col1.clone(), col2.clone()),
            )
            .to_string(),
            "(($col1 < $col2) or ($col1 != $col2))"
        );

        assert_eq!(not(col1.clone()).to_string(), "!$col1");

        assert_eq!(
            Select::include_expr(vec![Field::from("col1")], ident()).to_string(),
            "select +($col1) []"
        );
        assert_eq!(
            Select::include_expr(vec![Field::from("col1"), Field::from("col2")], ident())
                .to_string(),
            "select +($col1,$col2) []"
        );
        assert_eq!(
            Select::exclude_expr(
                vec![Field::from("col1"), Field::from("col2"), Field::Index(1),],
                ident()
            )
            .to_string(),
            "select -($col1,$col2,[1]) []"
        );

        assert_eq!(lit(Scalar::from(0_u8)).to_string(), "0_u8");
        assert_eq!(lit(Scalar::from(0.0_f32)).to_string(), "0_f32");
        assert_eq!(
            lit(Scalar::from(i64::MAX)).to_string(),
            "9223372036854775807_i64"
        );
        assert_eq!(lit(Scalar::from(true)).to_string(), "true");
        assert_eq!(
            lit(Scalar::null(DType::Bool(Nullability::Nullable))).to_string(),
            "null"
        );

        assert_eq!(
            lit(Scalar::struct_(
                DType::Struct(
                    StructDType::new(
                        Arc::from([Arc::from("dog"), Arc::from("cat")]),
                        vec![
                            DType::Primitive(PType::U32, Nullability::NonNullable),
                            DType::Utf8(Nullability::NonNullable)
                        ],
                    ),
                    Nullability::NonNullable
                ),
                vec![Scalar::from(32_u32), Scalar::from("rufus".to_string())]
            ))
            .to_string(),
            "{dog:32_u32,cat:rufus}"
        );
    }
}