arrow_data/transform/
union.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 super::{_MutableArrayData, Extend};
19use crate::ArrayData;
20use arrow_schema::DataType;
21
22pub(super) fn build_extend_sparse(array: &ArrayData) -> Extend<'_> {
23    let type_ids = array.buffer::<i8>(0);
24
25    Box::new(
26        move |mutable: &mut _MutableArrayData, index: usize, start: usize, len: usize| {
27            // extends type_ids
28            mutable
29                .buffer1
30                .extend_from_slice(&type_ids[start..start + len]);
31
32            mutable
33                .child_data
34                .iter_mut()
35                .for_each(|child| child.extend(index, start, start + len))
36        },
37    )
38}
39
40pub(super) fn build_extend_dense(array: &ArrayData) -> Extend<'_> {
41    let type_ids = array.buffer::<i8>(0);
42    let offsets = array.buffer::<i32>(1);
43    let arrow_schema::DataType::Union(src_fields, _) = array.data_type() else {
44        unreachable!();
45    };
46
47    Box::new(
48        move |mutable: &mut _MutableArrayData, index: usize, start: usize, len: usize| {
49            // extends type_ids
50            mutable
51                .buffer1
52                .extend_from_slice(&type_ids[start..start + len]);
53
54            (start..start + len).for_each(|i| {
55                let type_id = type_ids[i];
56                let child_index = src_fields
57                    .iter()
58                    .position(|(r, _)| r == type_id)
59                    .expect("invalid union type ID");
60                let src_offset = offsets[i] as usize;
61                let child_data = &mut mutable.child_data[child_index];
62                let dst_offset = child_data.len();
63
64                // Extend offsets
65                mutable.buffer2.push(dst_offset as i32);
66                mutable.child_data[child_index].extend(index, src_offset, src_offset + 1)
67            })
68        },
69    )
70}
71
72pub(super) fn extend_nulls_dense(mutable: &mut _MutableArrayData, len: usize) {
73    let DataType::Union(fields, _) = &mutable.data_type else {
74        unreachable!()
75    };
76    let first_type_id = fields
77        .iter()
78        .next()
79        .expect("union must have at least one field")
80        .0;
81
82    // Extend type_ids buffer
83    mutable.buffer1.extend_from_slice(&vec![first_type_id; len]);
84
85    // Dense: extend offsets pointing into the first child, then extend nulls in that child
86    let child_offset = mutable.child_data[0].len();
87    let (start, end) = (child_offset as i32, (child_offset + len) as i32);
88    mutable.buffer2.extend(start..end);
89    mutable.child_data[0].extend_nulls(len);
90}
91
92pub(super) fn extend_nulls_sparse(mutable: &mut _MutableArrayData, len: usize) {
93    let DataType::Union(fields, _) = &mutable.data_type else {
94        unreachable!()
95    };
96    let first_type_id = fields
97        .iter()
98        .next()
99        .expect("union must have at least one field")
100        .0;
101
102    // Extend type_ids buffer
103    mutable.buffer1.extend_from_slice(&vec![first_type_id; len]);
104
105    // Sparse: extend nulls in ALL children
106    mutable
107        .child_data
108        .iter_mut()
109        .for_each(|child| child.extend_nulls(len));
110}
arrow_data/transform/union.rs

arrow_data/transform/
union.rs
