Struct StructureColumnSummary 

pub struct StructureColumnSummary {
    pub name: String,
    pub data_type: DataType,
    pub total_count: Option<usize>,
    pub null_count: Option<usize>,
    pub null_ratio: Option<f64>,
    pub unique_count: Option<usize>,
    pub uniqueness_ratio: Option<f64>,
    pub distinct_count_approximate: Option<bool>,
    pub provenance: String,
}

Sample-derived or metadata-derived structural summary for one column.

The counters and the type answer to different sources, and provenance names the one that decided the type. A counter is present only when it describes the whole source: for CSV/JSON/JSONL that is the bounded structural sample, disclosed by rows_sampled and truncated; for Parquet the counts come from the file footer and cover every row, so they hold even when the type sample was truncated. None keeps its usual meaning — not analyzed — and is what a counter reports rather than a partial number (#700).

Fields

name: String

data_type: DataType

total_count: Option<usize>

null_count: Option<usize>

null_ratio: Option<f64>

unique_count: Option<usize>

uniqueness_ratio: Option<f64>

distinct_count_approximate: Option<bool>

provenance: String

Which source governs this column’s type: "metadata" when the declared schema decided it, "sample" when only the column’s values can. It names the source, not the read — a "sample" column is one the metadata could not type, whether or not the caller’s row budget allowed any row to be read for it. rows_sampled and truncated report the read.

CSV/JSON/JSONL are always "sample"; a Parquet file carries both, since only its text columns need values to be typed (#693).

Trait Implementations

impl Clone for StructureColumnSummary

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for StructureColumnSummary

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for StructureColumnSummary

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for StructureColumnSummary

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl Serialize for StructureColumnSummary

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 StructureColumnSummary