datafusion-common 48.0.0

Common functionality for DataFusion query engine
Documentation 
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

// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License.  You may obtain a copy of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied.  See the License for the
// specific language governing permissions and limitations
// under the License.

//! Utilities for working with strings

use arrow::array::{Array, AsArray};
use arrow::datatypes::DataType;

/// Convenient function to convert an Arrow string array to a vector of strings
pub fn string_array_to_vec(array: &dyn Array) -> Vec<Option<&str>> {
    match array.data_type() {
        DataType::Utf8 => array.as_string::<i32>().iter().collect(),
        DataType::LargeUtf8 => array.as_string::<i64>().iter().collect(),
        DataType::Utf8View => array.as_string_view().iter().collect(),
        _ => unreachable!(),
    }
}