Struct FileMetadata

pub struct FileMetadata {
    pub version: i32,
    pub num_rows: usize,
    pub max_row_group_height: 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.

Metadata for a Parquet file.

Fields

version: i32

version of this file.

num_rows: usize

number of rows in the file.

max_row_group_height: usize

Max row group height, useful for sharing column materializations.

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

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, ParquetError>

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

Trait Implementations

impl Clone for FileMetadata

fn clone(&self) -> FileMetadata

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for FileMetadata

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

Formats the value using the given formatter.