Enum ColumnCodec 

pub enum ColumnCodec {
    Auto,
    AlpFastLanesLz4,
    AlpRdLz4,
    PcodecLz4,
    DeltaFastLanesLz4,
    FastLanesLz4,
    FsstLz4,
    AlpFastLanesRans,
    DeltaFastLanesRans,
    FsstRans,
    Gorilla,
    DoubleDelta,
    Delta,
    Lz4,
    Zstd,
    Raw,
}

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

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

AlpFastLanesLz4

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

AlpRdLz4

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

PcodecLz4

f64/i64 complex: Pcodec → lz4.

DeltaFastLanesLz4

i64 timestamps/counters: Delta → FastLanes → lz4.

FastLanesLz4

i64/u32 raw integers: FastLanes → lz4.

FsstLz4

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

AlpFastLanesRans

f64 metrics cold: ALP → FastLanes → rANS.

DeltaFastLanesRans

i64 cold: Delta → FastLanes → rANS.

FsstRans

Strings cold: FSST → rANS.

Gorilla

Gorilla XOR encoding — legacy f64 codec.

DoubleDelta

DoubleDelta — legacy timestamp codec.

Delta

Delta + varint — legacy counter codec.

Lz4

LZ4 block compression — for string/log columns.

Zstd

Zstd — for cold/archived partitions.

Raw

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

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 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 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 Copy for ColumnCodec

impl Eq for ColumnCodec

impl StructuralPartialEq for ColumnCodec