Enum Compression 

pub enum Compression {
    UNCOMPRESSED,
    SNAPPY,
    GZIP(GzipLevel),
    LZO,
    BROTLI(BrotliLevel),
    LZ4,
    ZSTD(ZstdLevel),
    LZ4_RAW,
}

Supported block compression algorithms.

Block compression can yield non-trivial improvements to storage efficiency at the expense of potentially significantly worse encode and decode performance. Many applications, especially those making use of high-throughput and low-cost commodity object storage, may find storage efficiency less important than decode throughput, and therefore may wish to not make use of block compression.

The writers in this crate default to no block compression for this reason.

Applications that do still wish to use block compression, will find Compression::ZSTD to provide a good balance of compression, performance, and ecosystem support. Alternatively, Compression::LZ4_RAW provides much faster decompression speeds, at the cost of typically worse compression ratios. However, it is not as widely supported by the ecosystem, with the Hadoop ecosystem historically favoring the non-standard and now deprecated Compression::LZ4.

Variants

UNCOMPRESSED

No compression.

SNAPPY

Snappy compression

GZIP(GzipLevel)

Gzip compression

LZO

LZO compression

BROTLI(BrotliLevel)

Brotli compression

LZ4

LZ4 compression, (deprecated)

ZSTD(ZstdLevel)

ZSTD compression

LZ4_RAW

LZ4 compression.

Implementations

impl Compression

pub(crate) fn codec_to_string(self) -> String

Returns the codec type of this compression setting as a string, without the compression level.

Trait Implementations

impl Clone for Compression

fn clone(&self) -> Compression

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Compression

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

Formats the value using the given formatter.

impl Display for Compression

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

Formats the value using the given formatter.

impl FromStr for Compression

type Err = ParquetError

The associated error which can be returned from parsing.

fn from_str(s: &str) -> Result<Self, Self::Err>

Parses a string s to return a value of this type.

impl HeapSize for Compression

fn heap_size(&self) -> usize

Return the size of any bytes allocated on the heap by this object, including heap memory in those structures

impl PartialEq for Compression

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

Tests for self and other values to be equal, and is used by ==.

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

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

impl<'a, R: ThriftCompactInputProtocol<'a>> ReadThrift<'a, R> for Compression

fn read_thrift(prot: &mut R) -> Result<Self>

Read an object of type Self from the input protocol object.

impl WriteThrift for Compression

const ELEMENT_TYPE: ElementType = ElementType::I32

The ElementType to use when a list of this object is written.

fn write_thrift<W: Write>( &self, writer: &mut ThriftCompactOutputProtocol<W>, ) -> Result<()>

Serialize this object to the given writer.

impl WriteThriftField for Compression

fn write_thrift_field<W: Write>( &self, writer: &mut ThriftCompactOutputProtocol<W>, field_id: i16, last_field_id: i16, ) -> Result<i16>

Used to write struct fields (which may be primitive or IDL defined types). This will write the field marker for the given field_id, using last_field_id to compute the field delta used by the Thrift compact protocol. On success this will return field_id to be used in chaining.

impl Copy for Compression

impl Eq for Compression

impl StructuralPartialEq for Compression