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::{ArrowError, 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            for child in mutable.child_data.iter_mut() {
33                child.try_extend(index, start, start + len)?;
34            }
35            Ok(())
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            for i in start..start + len {
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].try_extend(index, src_offset, src_offset + 1)?;
67            }
68            Ok(())
69        },
70    )
71}
72
73pub(super) fn extend_nulls_dense(
74    mutable: &mut _MutableArrayData,
75    len: usize,
76) -> Result<(), ArrowError> {
77    let DataType::Union(fields, _) = &mutable.data_type else {
78        unreachable!()
79    };
80    let first_type_id = fields
81        .iter()
82        .next()
83        .expect("union must have at least one field")
84        .0;
85
86    // Extend type_ids buffer
87    mutable.buffer1.extend_from_slice(&vec![first_type_id; len]);
88
89    // Dense: extend offsets pointing into the first child, then extend nulls in that child
90    let child_offset = mutable.child_data[0].len();
91    let (start, end) = (child_offset as i32, (child_offset + len) as i32);
92    mutable.buffer2.extend(start..end);
93    mutable.child_data[0].try_extend_nulls(len)?;
94    Ok(())
95}
96
97pub(super) fn extend_nulls_sparse(
98    mutable: &mut _MutableArrayData,
99    len: usize,
100) -> Result<(), ArrowError> {
101    let DataType::Union(fields, _) = &mutable.data_type else {
102        unreachable!()
103    };
104    let first_type_id = fields
105        .iter()
106        .next()
107        .expect("union must have at least one field")
108        .0;
109
110    // Extend type_ids buffer
111    mutable.buffer1.extend_from_slice(&vec![first_type_id; len]);
112
113    // Sparse: extend nulls in ALL children
114    for child in mutable.child_data.iter_mut() {
115        child.try_extend_nulls(len)?;
116    }
117    Ok(())
118}
arrow_data/transform/union.rs

arrow_data/transform/
union.rs
