Struct Schema 

pub struct Schema { /* private fields */ }

A schema defines the column names and their order in a row.

Implementations

impl Schema

pub fn new(columns: Vec<String>) -> Self

Creates a new schema from column names.

pub fn from_arcs(columns: Vec<Arc<str>>) -> Self

Creates a new schema from Arc<str> column names (avoids allocation).

pub fn empty() -> Self

Creates an empty schema.

pub fn columns(&self) -> Vec<&str>

Returns the column names as string slices.

pub fn columns_arc(&self) -> &[Arc<str>]

Returns the Arc<str> column names (for efficient cloning).

pub fn len(&self) -> usize

Returns the number of columns.

pub fn is_empty(&self) -> bool

Returns true if the schema has no columns.

pub fn index_of(&self, name: &str) -> Option<usize>

Gets the index for a column name.

pub fn column_at(&self, index: usize) -> Option<&str>

Gets the column name at an index.

pub fn with_column(&self, name: impl Into<String>) -> Self

Creates a new schema with an additional column.

pub fn merge(&self, other: &Schema) -> Self

Creates a new schema by merging with another (efficiently clones Arc<str>).

pub fn project(&self, indices: &[usize]) -> Self

Creates a projection of this schema with only the given columns.

Trait Implementations

impl Clone for Schema

fn clone(&self) -> Schema

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Schema

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

Formats the value using the given formatter.

impl Default for Schema

fn default() -> Self

Returns the “default value” for a type.

impl From<Vec<&str>> for Schema

fn from(columns: Vec<&str>) -> Self

Converts to this type from the input type.

impl From<Vec<String>> for Schema

fn from(columns: Vec<String>) -> Self

Converts to this type from the input type.

impl PartialEq for Schema

fn eq(&self, other: &Schema) -> 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 Eq for Schema

impl StructuralPartialEq for Schema