Struct datafusion::prelude::Column

pub struct Column {
    pub relation: Option<String>,
    pub name: String,
}

A named reference to a qualified field in a schema.

Fields

relation: Option<String>

relation/table name.

name: String

field/column name.

Implementations

impl Column

pub fn from_name(name: impl Into<String>) -> Self

Create Column from unqualified name.

pub fn from_qualified_name(flat_name: &str) -> Self

Deserialize a fully qualified name string into a column

pub fn flat_name(&self) -> String

Serialize column into a flat name string

pub fn normalize(self, plan: &LogicalPlan) -> Result<Self>

Normalizes self if is unqualified (has no relation name) with an explicit qualifier from the first matching input schemas.

For example, foo will be normalized to t.foo if there is a column named foo in a relation named t found in schemas

Trait Implementations

impl Clone for Column

fn clone(&self) -> Column

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Column

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

Formats the value using the given formatter.

impl Display for Column

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

Formats the value using the given formatter.

impl From<&'_ str> for Column

fn from(c: &str) -> Self

Performs the conversion.

impl FromStr for Column

type Err = Infallible

The associated error which can be returned from parsing.

fn from_str(s: &str) -> Result<Self, Self::Err>

Parses a string s to return a value of this type.

impl Hash for Column

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, 

Feeds a slice of this type into the given Hasher.

impl Ord for Column

fn cmp(&self, other: &Column) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

Restrict a value to a certain interval.

impl PartialEq<Column> for Column

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

This method tests for self and other values to be equal, and is used by ==.

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

This method tests for !=.

impl PartialOrd<Column> for Column

fn partial_cmp(&self, other: &Column) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

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

This method tests less than (for self and other) and is used by the < operator.

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

This method tests less than or equal to (for self and other) and is used by the <= operator.

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

This method tests greater than (for self and other) and is used by the > operator.

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

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl Eq for Column

impl StructuralEq for Column

impl StructuralPartialEq for Column