Struct arrow2::io::parquet::write::ThriftFileMetaData

pub struct ThriftFileMetaData {
    pub version: i32,
    pub schema: Vec<SchemaElement, Global>,
    pub num_rows: i64,
    pub row_groups: Vec<RowGroup, Global>,
    pub key_value_metadata: Option<Vec<KeyValue, Global>>,
    pub created_by: Option<String>,
    pub column_orders: Option<Vec<ColumnOrder, Global>>,
    pub encryption_algorithm: Option<EncryptionAlgorithm>,
    pub footer_signing_key_metadata: Option<Vec<u8, Global>>,
}

Available on crate feature io_parquet only.

Description for file metadata

Fields

version: i32

Version of this file *

schema: Vec<SchemaElement, Global>

Parquet schema for this file. This schema contains metadata for all the columns. The schema is represented as a tree with a single root. The nodes of the tree are flattened to a list by doing a depth-first traversal. The column metadata contains the path in the schema for that column which can be used to map columns to nodes in the schema. The first element is the root *

num_rows: i64

Number of rows in this file *

row_groups: Vec<RowGroup, Global>

Row groups in this file *

key_value_metadata: Option<Vec<KeyValue, Global>>

Optional key/value metadata *

created_by: Option<String>

String for application that wrote this file. This should be in the format version (build ). e.g. impala version 1.0 (build 6cf94d29b2b7115df4de2c06e2ab4326d721eb55)

column_orders: Option<Vec<ColumnOrder, Global>>

Sort order used for the min_value and max_value fields in the Statistics objects and the min_values and max_values fields in the ColumnIndex objects of each column in this file. Sort orders are listed in the order matching the columns in the schema. The indexes are not necessary the same though, because only leaf nodes of the schema are represented in the list of sort orders.

Without column_orders, the meaning of the min_value and max_value fields in the Statistics object and the ColumnIndex object is undefined. To ensure well-defined behaviour, if these fields are written to a Parquet file, column_orders must be written as well.

The obsolete min and max fields in the Statistics object are always sorted by signed comparison regardless of column_orders.

encryption_algorithm: Option<EncryptionAlgorithm>

Encryption algorithm. This field is set only in encrypted files with plaintext footer. Files with encrypted footer store algorithm id in FileCryptoMetaData structure.

footer_signing_key_metadata: Option<Vec<u8, Global>>

Retrieval metadata of key used for signing the footer. Used only in encrypted files with plaintext footer.

Implementations

impl FileMetaData

pub fn new<F5, F6, F7, F8, F9>(
    version: i32,
    schema: Vec<SchemaElement, Global>,
    num_rows: i64,
    row_groups: Vec<RowGroup, Global>,
    key_value_metadata: F5,
    created_by: F6,
    column_orders: F7,
    encryption_algorithm: F8,
    footer_signing_key_metadata: F9
) -> FileMetaData where
    F5: Into<Option<Vec<KeyValue, Global>>>,
    F6: Into<Option<String>>,
    F7: Into<Option<Vec<ColumnOrder, Global>>>,
    F8: Into<Option<EncryptionAlgorithm>>,
    F9: Into<Option<Vec<u8, Global>>>, 

pub fn read_from_in_protocol<T>(i_prot: &mut T) -> Result<FileMetaData, Error> where
    T: TInputProtocol, 

pub async fn stream_from_in_protocol<T>(
    i_prot: &mut T
) -> Result<FileMetaData, Error> where
    T: TInputStreamProtocol, 

pub fn write_to_out_protocol<T>(&self, o_prot: &mut T) -> Result<usize, Error> where
    T: TOutputProtocol, 

pub async fn write_to_out_stream_protocol<T>(
    &self,
    o_prot: &mut T
) -> Result<usize, Error> where
    T: TOutputStreamProtocol, 

Trait Implementations

impl AsyncReadThrift for FileMetaData

fn stream_from_in_protocol<'life0, 'async_trait, T>(
    i_prot: &'life0 mut T
) -> Pin<Box<dyn Future<Output = Result<FileMetaData, Error>> + Send + 'async_trait, Global>> where
    'life0: 'async_trait,
    T: 'async_trait + TInputStreamProtocol, 

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.

impl Hash for FileMetaData

fn hash<__H>(&self, state: &mut __H) where
    __H: Hasher, 

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given Hasher.

impl Ord for FileMetaData

fn cmp(&self, other: &FileMetaData) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self where
    Self: PartialOrd<Self>, 

Restrict a value to a certain interval.

impl PartialEq<FileMetaData> for FileMetaData

fn eq(&self, other: &FileMetaData) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd<FileMetaData> for FileMetaData

fn partial_cmp(&self, other: &FileMetaData) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl ReadThrift for FileMetaData

fn read_from_in_protocol<T>(i_prot: &mut T) -> Result<FileMetaData, Error> where
    T: TInputProtocol, 

impl Eq for FileMetaData

impl StructuralEq for FileMetaData

impl StructuralPartialEq for FileMetaData