Enum ColumnCodec 

#[repr(u8)]
pub enum ColumnCodec {
    Auto = 0,
    AlpFastLanesLz4 = 1,
    AlpRdLz4 = 2,
    PcodecLz4 = 3,
    DeltaFastLanesLz4 = 4,
    FastLanesLz4 = 5,
    FsstLz4 = 6,
    AlpFastLanesRans = 7,
    DeltaFastLanesRans = 8,
    FsstRans = 9,
    Gorilla = 10,
    DoubleDelta = 11,
    Delta = 12,
    Lz4 = 13,
    Zstd = 14,
    Raw = 15,
}

Codec identifier for per-column compression selection.

Stored in partition schema metadata so the reader knows which decoder to use for each column file.

Variants

Auto = 0

Engine selects codec automatically based on column type and data distribution (analyzed at flush time).

AlpFastLanesLz4 = 1

f64 metrics: ALP (decimal→int) → FastLanes → lz4.

AlpRdLz4 = 2

f64 true doubles: ALP-RD (front-bit dict) → lz4.

PcodecLz4 = 3

f64/i64 complex: Pcodec → lz4.

DeltaFastLanesLz4 = 4

i64 timestamps/counters: Delta → FastLanes → lz4.

FastLanesLz4 = 5

i64/u32 raw integers: FastLanes → lz4.

FsstLz4 = 6

Strings/logs: FSST (substring dict) → lz4.

AlpFastLanesRans = 7

f64 metrics cold: ALP → FastLanes → rANS.

DeltaFastLanesRans = 8

i64 cold: Delta → FastLanes → rANS.

FsstRans = 9

Strings cold: FSST → rANS.

Gorilla = 10

Gorilla XOR encoding — f64 codec selected by detect.rs for float columns.

DoubleDelta = 11

DoubleDelta — timestamp codec selected by detect.rs for monotonic timestamp columns.

Delta = 12

Delta + varint — counter codec selected by detect.rs for integer delta columns.

Lz4 = 13

LZ4 block compression — for string/log columns.

Zstd = 14

Zstd — for cold/archived partitions.

Raw = 15

No compression — for pre-compressed or symbol columns.

Implementations

impl ColumnCodec

pub fn is_compressed(&self) -> bool

pub fn is_cascading(&self) -> bool

Whether this is a cascading (multi-stage) codec.

pub fn is_cold_tier(&self) -> bool

Whether this codec uses rANS as terminal (cold tier).

pub fn as_str(&self) -> &'static str

pub fn try_resolve(self) -> Result<ResolvedColumnCodec, CodecError>

Resolve Auto to a concrete codec using the provided detection result, or return an error if this is called with Auto where a concrete value is required (i.e. a caller forgot to run detection first).

For callers that have already run detection and hold a non-Auto codec, this is a zero-cost newtype wrap.

Trait Implementations

impl Clone for ColumnCodec

fn clone(&self) -> ColumnCodec

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for ColumnCodec

impl Debug for ColumnCodec

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for ColumnCodec

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for ColumnCodec

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

Formats the value using the given formatter.

impl Eq for ColumnCodec

impl<'__msgpack_de> FromMessagePack<'__msgpack_de> for ColumnCodec

fn read<R: Read<'__msgpack_de>>(reader: &mut R) -> Result<Self, Error>

where Self: Sized,

Reads the MessagePack representation of this value from the provided reader.

impl Hash for ColumnCodec

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 PartialEq for ColumnCodec

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

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for ColumnCodec

impl ToMessagePack for ColumnCodec

fn write<W: Write>(&self, writer: &mut W) -> Result<(), Error>

Writes the MessagePack representation of this value into the provided writer.