Function substr

datafusion/functions/src/unicode/substr.rs:133–152

Dispatches `substr` to the appropriate string array implementation.

(args: &[ArrayRef])

/// Dispatches `substr` to the appropriate string array implementation.
fn substr(args: &[ArrayRef]) -> Result<ArrayRef> {
    match args[0].data_type() {
        DataType::Utf8 => {
            let string_array = args[0].as_string::<i32>();
            generic_string_substr(string_array, &args[1..])
        }
        DataType::LargeUtf8 => {
            let string_array = args[0].as_string::<i64>();
            generic_string_substr(string_array, &args[1..])
        }
        DataType::Utf8View => {
            let string_array = args[0].as_string_view();
            string_view_substr(string_array, &args[1..])
        }
        other => exec_err!(
            "Unsupported data type {other:?} for function substr,\
            expected Utf8View, Utf8 or LargeUtf8."
        ),
    }
}

/// Convert the given `start` and `count` to valid byte indices within `input` string.
///