Enum Encoding 

pub enum Encoding {
    Plain = 0,
    PlainDictionary = 2,
    Rle = 3,
    BitPacked = 4,
    DeltaBinaryPacked = 5,
    DeltaLengthByteArray = 6,
    DeltaByteArray = 7,
    RleDictionary = 8,
    ByteStreamSplit = 9,
}

Encodings supported by Parquet. Not all encodings are valid for all types. These enums are also used to specify the encoding of definition and repetition levels. See the accompanying doc for the details of the more complicated encodings.

Variants

Plain = 0

Default encoding. BOOLEAN - 1 bit per value. 0 is false; 1 is true. INT32 - 4 bytes per value. Stored as little-endian. INT64 - 8 bytes per value. Stored as little-endian. FLOAT - 4 bytes per value. IEEE. Stored as little-endian. DOUBLE - 8 bytes per value. IEEE. Stored as little-endian. BYTE_ARRAY - 4 byte length stored as little endian, followed by bytes. FIXED_LEN_BYTE_ARRAY - Just the bytes.

PlainDictionary = 2

Deprecated: Dictionary encoding. The values in the dictionary are encoded in the plain type. in a data page use RLE_DICTIONARY instead. in a Dictionary page use PLAIN instead

Rle = 3

Group packed run length encoding. Usable for definition/repetition levels encoding and Booleans (on one bit: 0 is false; 1 is true.)

BitPacked = 4

Bit packed encoding. This can only be used if the data has a known max width. Usable for definition/repetition levels encoding.

DeltaBinaryPacked = 5

Delta encoding for integers. This can be used for int columns and works best on sorted data

DeltaLengthByteArray = 6

Encoding for byte arrays to separate the length values and the data. The lengths are encoded using DELTA_BINARY_PACKED

DeltaByteArray = 7

Incremental-encoded byte array. Prefix lengths are encoded using DELTA_BINARY_PACKED. Suffixes are stored as delta length byte arrays.

RleDictionary = 8

Dictionary encoding: the ids are encoded using the RLE encoding

ByteStreamSplit = 9

Encoding for floating-point data. K byte-streams are created where K is the size in bytes of the data type. The individual bytes of an FP value are scattered to the corresponding stream and the streams are concatenated. This itself does not reduce the size of the data but can lead to better compression afterwards.

Implementations

impl Encoding

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

pub fn read_from_in_protocol( i_prot: &mut dyn TInputProtocol, ) -> Result<Encoding>

Trait Implementations

impl Clone for Encoding

fn clone(&self) -> Encoding

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for Encoding

impl Debug for Encoding

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

Formats the value using the given formatter.

impl Eq for Encoding

impl Hash for Encoding

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 Encoding

fn cmp(&self, other: &Encoding) -> 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,

Restrict a value to a certain interval.

fn clamp_to<R>(self, range: R) -> Self

where Self: Sized, R: ClampBounds<Self>,

🔬This is a nightly-only experimental API. (clamp_to)

Restrict a value to a certain range.

impl PartialEq for Encoding

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

Equality operator ==.

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

Inequality operator !=.

impl PartialOrd for Encoding

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

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

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

Tests less than (for self and other) and is used by the < operator.

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

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

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

Tests greater than (for self and other) and is used by the > operator.

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

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

impl StructuralPartialEq for Encoding

impl TryFrom<i32> for Encoding

type Error = Error

The type returned in the event of a conversion error.

fn try_from(i: i32) -> Result<Self, Self::Error>

Performs the conversion.