Struct parquet_format_safe::PageHeader

pub struct PageHeader {
    pub type_: PageType,
    pub uncompressed_page_size: i32,
    pub compressed_page_size: i32,
    pub crc: Option<i32>,
    pub data_page_header: Option<DataPageHeader>,
    pub index_page_header: Option<IndexPageHeader>,
    pub dictionary_page_header: Option<DictionaryPageHeader>,
    pub data_page_header_v2: Option<DataPageHeaderV2>,
}

Fields

type_: PageType

the type of the page: indicates which of the *_header fields is set *

uncompressed_page_size: i32

Uncompressed page size in bytes (not including this header) *

compressed_page_size: i32

Compressed (and potentially encrypted) page size in bytes, not including this header *

crc: Option<i32>

The 32bit CRC for the page, to be be calculated as follows:

• Using the standard CRC32 algorithm
• On the data only, i.e. this header should not be included. ‘Data’ hereby refers to the concatenation of the repetition levels, the definition levels and the column value, in this exact order.
• On the encoded versions of the repetition levels, definition levels and column values
• On the compressed versions of the repetition levels, definition levels and column values where possible;
  • For v1 data pages, the repetition levels, definition levels and column values are always compressed together. If a compression scheme is specified, the CRC shall be calculated on the compressed version of this concatenation. If no compression scheme is specified, the CRC shall be calculated on the uncompressed version of this concatenation.
  • For v2 data pages, the repetition levels and definition levels are handled separately from the data and are never compressed (only encoded). If a compression scheme is specified, the CRC shall be calculated on the concatenation of the uncompressed repetition levels, uncompressed definition levels and the compressed column values. If no compression scheme is specified, the CRC shall be calculated on the uncompressed concatenation.
• In encrypted columns, CRC is calculated after page encryption; the encryption itself is performed after page compression (if compressed) If enabled, this allows for disabling checksumming in HDFS if only a few pages need to be read.

data_page_header: Option<DataPageHeader>

index_page_header: Option<IndexPageHeader>

dictionary_page_header: Option<DictionaryPageHeader>

data_page_header_v2: Option<DataPageHeaderV2>

Implementations

impl PageHeader

pub fn new<F4, F5, F6, F7, F8>( type_: PageType, uncompressed_page_size: i32, compressed_page_size: i32, crc: F4, data_page_header: F5, index_page_header: F6, dictionary_page_header: F7, data_page_header_v2: F8 ) -> PageHeader

where F4: Into<Option<i32>>, F5: Into<Option<DataPageHeader>>, F6: Into<Option<IndexPageHeader>>, F7: Into<Option<DictionaryPageHeader>>, F8: Into<Option<DataPageHeaderV2>>,

pub fn read_from_in_protocol<T: TInputProtocol>( i_prot: &mut T ) -> Result<PageHeader>

pub async fn stream_from_in_protocol<T: TInputStreamProtocol>( i_prot: &mut T ) -> Result<PageHeader>

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

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

Trait Implementations

impl AsyncReadThrift for PageHeader

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

where T: 'async_trait + TInputStreamProtocol, 'life0: 'async_trait,

impl Clone for PageHeader

fn clone(&self) -> PageHeader

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for PageHeader

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

Formats the value using the given formatter.

impl Hash for PageHeader

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

Feeds this value into the given Hasher.

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

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for PageHeader

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

This method returns an Ordering between self and other.

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

where Self: Sized,

Compares and returns the maximum of two values.

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

where Self: Sized,

Compares and returns the minimum of two values.

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

where Self: Sized + PartialOrd,

Restrict a value to a certain interval.

impl PartialEq for PageHeader

fn eq(&self, other: &PageHeader) -> 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 for PageHeader

fn partial_cmp(&self, other: &PageHeader) -> 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 PageHeader

fn read_from_in_protocol<T: TInputProtocol>( i_prot: &mut T ) -> Result<PageHeader>

impl Eq for PageHeader

impl StructuralPartialEq for PageHeader