arrow/examples/read_csv_infer_schema.rs

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// to you under the Apache License, Version 2.0 (the
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//
//   http://www.apache.org/licenses/LICENSE-2.0
//
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extern crate arrow;

#[cfg(feature = "csv")]
use arrow::csv;
#[cfg(feature = "prettyprint")]
use arrow::util::pretty::print_batches;
use std::fs::File;

fn main() {
    #[cfg(feature = "csv")]
    {
        let file = File::open("test/data/uk_cities_with_headers.csv").unwrap();
        let builder = csv::ReaderBuilder::new()
            .has_header(true)
            .infer_schema(Some(100));
        let mut csv = builder.build(file).unwrap();
        let _batch = csv.next().unwrap().unwrap();
        #[cfg(feature = "prettyprint")]
        {
            print_batches(&[_batch]).unwrap();
        }
    }
}