Enum arrow2::io::parquet::write::Encoding

pub enum Encoding {
    Plain,
    PlainDictionary,
    Rle,
    BitPacked,
    DeltaBinaryPacked,
    DeltaLengthByteArray,
    DeltaByteArray,
    RleDictionary,
    ByteStreamSplit,
}

Available on crate feature io_parquet only.

Variants

Plain

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

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

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

BitPacked

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

DeltaBinaryPacked

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

DeltaLengthByteArray

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

DeltaByteArray

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

RleDictionary

Dictionary encoding: the ids are encoded using the RLE encoding

ByteStreamSplit

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.

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<(), Error>

Formats the value using the given formatter.

impl Hash for Encoding

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 PartialEq<Encoding> for Encoding

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

type Error = Error

The type returned in the event of a conversion error.

fn try_from(
    encoding: Encoding
) -> Result<Encoding, <Encoding as TryFrom<Encoding>>::Error>

Performs the conversion.

impl Copy for Encoding

impl Eq for Encoding

impl StructuralEq for Encoding

impl StructuralPartialEq for Encoding