Struct Encoding

pub struct Encoding(pub i32);

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.

Tuple Fields

0: i32

Implementations

impl Encoding

pub const PLAIN: Encoding

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.

pub const PLAIN_DICTIONARY: Encoding

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

pub const RLE: Encoding

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

pub const BIT_PACKED: Encoding

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

pub const DELTA_BINARY_PACKED: Encoding

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

pub const DELTA_LENGTH_BYTE_ARRAY: Encoding

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

pub const DELTA_BYTE_ARRAY: Encoding

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

pub const RLE_DICTIONARY: Encoding

Dictionary encoding: the ids are encoded using the RLE encoding

pub const BYTE_STREAM_SPLIT: Encoding

Encoding for fixed-width data (FLOAT, DOUBLE, INT32, INT64, FIXED_LEN_BYTE_ARRAY). K byte-streams are created where K is the size in bytes of the data type. The individual bytes of a 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.

Added in 2.8 for FLOAT and DOUBLE. Support for INT32, INT64 and FIXED_LEN_BYTE_ARRAY added in 2.11.

pub const ENUM_VALUES: &'static [Self]

Trait Implementations

impl Clone for Encoding

fn clone(&self) -> Encoding

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Encoding

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

Formats the value using the given formatter.

impl From<&Encoding> for i32

fn from(e: &Encoding) -> i32

Converts to this type from the input type.

impl From<&i32> for Encoding

fn from(i: &i32) -> Self

Converts to this type from the input type.

impl From<Encoding> for Encoding

fn from(value: Encoding) -> Self

Converts to this type from the input type.

impl From<Encoding> for i32

fn from(e: Encoding) -> i32

Converts to this type from the input type.

impl From<i32> for Encoding

fn from(i: i32) -> Self

Converts to this type from the input type.

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.

impl PartialEq for Encoding

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

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

Writes the struct to the output Thrift protocol

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

Reads the struct from the input Thrift protocol

impl TryFrom<Encoding> for Encoding

type Error = ParquetError

The type returned in the event of a conversion error.

fn try_from(value: Encoding) -> Result<Self>

Performs the conversion.

impl Copy for Encoding

impl Eq for Encoding

impl StructuralPartialEq for Encoding