Struct SchemaFingerprint 

pub struct SchemaFingerprint {
    pub schema_hash: [u8; 32],
    pub field_stats: Vec<FieldStats>,
    pub record_count: u64,
    pub created_at: u64,
}

Fingerprint that identifies a schema structure plus its data distribution.

Two SchemaFingerprints with equal schema_hash are structurally identical (same field names and kinds, regardless of order). The field_stats carry distribution information used by the nearest-neighbor warm-start heuristic.

Fields

schema_hash: [u8; 32]

SHA-256 of sorted (name, kind) pairs, stable across field-ordering.

field_stats: Vec<FieldStats>

One entry per schema field; empty when built with Self::from_schema.

record_count: u64

Number of records in the sample; 0 when built with Self::from_schema.

created_at: u64

Unix timestamp (seconds) when this fingerprint was created.

Implementations

impl SchemaFingerprint

pub fn from_schema(schema: &Schema) -> Self

Build a structure-only fingerprint from a schema definition.

field_stats is populated with zero-value statistics for each field so that the Jaccard similarity computation in crate::similarity can always access the field names and kinds, even without sample data.

pub fn from_schema_with_mappings( schema: &Schema, mappings: &[FieldMapping], ) -> Self

Like Self::from_schema but includes cross-schema mappings in the hash so warm-start artifacts from same-schema runs are never reused.

pub fn from_sample(schema: &Schema, records: &[Record]) -> Self

Build a full fingerprint from a schema and a sample of records.

50–100 records per field is typically enough for reliable statistics. The schema_hash is identical to what Self::from_schema would produce for the same schema, so exact-hash lookups still work.

pub fn from_sample_with_mappings( schema: &Schema, records: &[Record], mappings: &[FieldMapping], ) -> Self

Like Self::from_sample but includes cross-schema mappings in the hash.

Trait Implementations

impl Clone for SchemaFingerprint

fn clone(&self) -> SchemaFingerprint

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for SchemaFingerprint

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for SchemaFingerprint

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for SchemaFingerprint

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

where __S: Serializer,

Serialize this value into the given Serde serializer.