Struct polars::prelude::FileMetaData

pub struct FileMetaData {
    pub version: i32,
    pub num_rows: usize,
    pub created_by: Option<String>,
    pub row_groups: Vec<RowGroupMetaData>,
    pub key_value_metadata: Option<Vec<KeyValue>>,
    pub schema_descr: SchemaDescriptor,
    pub column_orders: Option<Vec<ColumnOrder>>,
}
Available on crate feature polars-io only.
Expand description

Metadata for a Parquet file.

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§version: i32

version of this file.

§num_rows: usize

number of rows in the file.

§created_by: Option<String>

String message for application that wrote this file.

This should have the following format: <application> version <application version> (build <application build hash>).

parquet-mr version 1.8.0 (build 0fda28af84b9746396014ad6a415b90592a98b3b)
§row_groups: Vec<RowGroupMetaData>

The row groups of this file

§key_value_metadata: Option<Vec<KeyValue>>

key_value_metadata of this file.

§schema_descr: SchemaDescriptor

schema descriptor.

§column_orders: Option<Vec<ColumnOrder>>

Column (sort) order used for min and max values of each column in this file.

Each column order corresponds to one column, determined by its position in the list, matching the position of the column in the schema.

When None is returned, there are no column orders available, and each column should be assumed to have undefined (legacy) column order.

Implementations§

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impl FileMetaData

pub fn schema(&self) -> &SchemaDescriptor

Returns the [SchemaDescriptor] that describes schema of this file.

pub fn key_value_metadata(&self) -> &Option<Vec<KeyValue>>

returns the metadata

pub fn column_order(&self, i: usize) -> ColumnOrder

Returns column order for ith column in this file. If column orders are not available, returns undefined (legacy) column order.

pub fn try_from_thrift(metadata: FileMetaData) -> Result<FileMetaData, Error>

Deserializes [crate::parquet::thrift_format::FileMetaData] into this struct

pub fn into_thrift(self) -> FileMetaData

Serializes itself to thrift’s [parquet_format_safe::FileMetaData].

Trait Implementations§

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impl Clone for FileMetaData

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fn clone(&self) -> FileMetaData

Returns a copy of the value. Read more
1.0.0 · source§

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source. Read more
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impl Debug for FileMetaData

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fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter. Read more

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Converts self into a Left variant of Either<Self, Self> if into_left is true. Converts self into a Right variant of Either<Self, Self> otherwise. Read more
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const ALIGN: usize = _

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type Init = T

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Initializes a with the given initializer. Read more
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