Struct arrow::json::reader::ReaderBuilder [−][src]
pub struct ReaderBuilder { /* fields omitted */ }
JSON file reader builder
Implementations
impl ReaderBuilder
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impl ReaderBuilder
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Create a new builder for configuring JSON parsing options.
To convert a builder into a reader, call Reader::from_builder
Example
extern crate arrow; use arrow::json; use std::fs::File; fn example() -> json::Reader<File> { let file = File::open("test/data/basic.json").unwrap(); // create a builder, inferring the schema with the first 100 records let builder = json::ReaderBuilder::new().infer_schema(Some(100)); let reader = builder.build::<File>(file).unwrap(); reader }
pub fn with_schema(self, schema: SchemaRef) -> Self
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Set the JSON file’s schema
pub fn infer_schema(self, max_records: Option<usize>) -> Self
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Set the JSON reader to infer the schema of the file
pub fn with_batch_size(self, batch_size: usize) -> Self
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Set the batch size (number of records to load at one time)
pub fn with_projection(self, projection: Vec<String>) -> Self
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Set the reader’s column projection
pub fn build<R>(self, source: R) -> Result<Reader<R>> where
R: Read + Seek,
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R: Read + Seek,
Create a new Reader
from the ReaderBuilder
Trait Implementations
impl Default for ReaderBuilder
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impl Default for ReaderBuilder
[src]Auto Trait Implementations
impl RefUnwindSafe for ReaderBuilder
impl RefUnwindSafe for ReaderBuilder
impl Send for ReaderBuilder
impl Send for ReaderBuilder
impl Sync for ReaderBuilder
impl Sync for ReaderBuilder
impl Unpin for ReaderBuilder
impl Unpin for ReaderBuilder
impl UnwindSafe for ReaderBuilder
impl UnwindSafe for ReaderBuilder