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
use std::any::Any;
use std::sync::Arc;
use crate::error::{ExecutionError, Result};
use crate::physical_plan::{ExecutionPlan, Partitioning};
use arrow::datatypes::SchemaRef;
use arrow::error::Result as ArrowResult;
use arrow::record_batch::{RecordBatch, RecordBatchReader};
use super::SendableRecordBatchReader;
use async_trait::async_trait;
#[derive(Debug)]
pub struct MemoryExec {
partitions: Vec<Vec<RecordBatch>>,
schema: SchemaRef,
projection: Option<Vec<usize>>,
}
#[async_trait]
impl ExecutionPlan for MemoryExec {
fn as_any(&self) -> &dyn Any {
self
}
fn schema(&self) -> SchemaRef {
self.schema.clone()
}
fn children(&self) -> Vec<Arc<dyn ExecutionPlan>> {
vec![]
}
fn output_partitioning(&self) -> Partitioning {
Partitioning::UnknownPartitioning(self.partitions.len())
}
fn with_new_children(
&self,
_: Vec<Arc<dyn ExecutionPlan>>,
) -> Result<Arc<dyn ExecutionPlan>> {
Err(ExecutionError::General(format!(
"Children cannot be replaced in {:?}",
self
)))
}
async fn execute(&self, partition: usize) -> Result<SendableRecordBatchReader> {
Ok(Box::new(MemoryIterator::try_new(
self.partitions[partition].clone(),
self.schema.clone(),
self.projection.clone(),
)?))
}
}
impl MemoryExec {
pub fn try_new(
partitions: &Vec<Vec<RecordBatch>>,
schema: SchemaRef,
projection: Option<Vec<usize>>,
) -> Result<Self> {
Ok(Self {
partitions: partitions.clone(),
schema,
projection,
})
}
}
pub(crate) struct MemoryIterator {
data: Vec<RecordBatch>,
schema: SchemaRef,
projection: Option<Vec<usize>>,
index: usize,
}
impl MemoryIterator {
pub fn try_new(
data: Vec<RecordBatch>,
schema: SchemaRef,
projection: Option<Vec<usize>>,
) -> Result<Self> {
Ok(Self {
data: data.clone(),
schema: schema.clone(),
projection,
index: 0,
})
}
}
impl Iterator for MemoryIterator {
type Item = ArrowResult<RecordBatch>;
fn next(&mut self) -> Option<Self::Item> {
if self.index < self.data.len() {
self.index += 1;
let batch = &self.data[self.index - 1];
match &self.projection {
Some(columns) => Some(RecordBatch::try_new(
self.schema.clone(),
columns.iter().map(|i| batch.column(*i).clone()).collect(),
)),
None => Some(Ok(batch.clone())),
}
} else {
None
}
}
}
impl RecordBatchReader for MemoryIterator {
fn schema(&self) -> SchemaRef {
self.schema.clone()
}
}