Enum Expression 

pub enum Expression {
    Literal(Literal),
    Column(ColumnRef),
    BinaryOp {
        left: Box<Expression>,
        op: BinaryOperator,
        right: Box<Expression>,
    },
    UnaryOp {
        op: UnaryOperator,
        expr: Box<Expression>,
    },
    Function {
        name: String,
        args: Vec<Expression>,
        distinct: bool,
    },
    Case {
        operand: Option<Box<Expression>>,
        conditions: Vec<(Expression, Expression)>,
        else_result: Option<Box<Expression>>,
    },
    Cast {
        expr: Box<Expression>,
        data_type: DataType,
    },
    InList {
        expr: Box<Expression>,
        list: Vec<Expression>,
        negated: bool,
    },
    InSubquery {
        expr: Box<Expression>,
        subquery: Box<SelectStatement>,
        negated: bool,
    },
    Between {
        expr: Box<Expression>,
        low: Box<Expression>,
        high: Box<Expression>,
        negated: bool,
    },
    Like {
        expr: Box<Expression>,
        pattern: Box<Expression>,
        negated: bool,
    },
    IsNull {
        expr: Box<Expression>,
        negated: bool,
    },
    Exists {
        subquery: Box<SelectStatement>,
        negated: bool,
    },
    Subquery(Box<SelectStatement>),
    Placeholder(usize),
}

An expression in SQL.

Variants

Literal(Literal)

Column(ColumnRef)

BinaryOp

Fields

left: Box<Expression>

op: BinaryOperator

right: Box<Expression>

UnaryOp

Fields

op: UnaryOperator

expr: Box<Expression>

Function

Fields

name: String

args: Vec<Expression>

distinct: bool

Case

Fields

operand: Option<Box<Expression>>

conditions: Vec<(Expression, Expression)>

else_result: Option<Box<Expression>>

Cast

Fields

expr: Box<Expression>

data_type: DataType

InList

Fields

expr: Box<Expression>

list: Vec<Expression>

negated: bool

InSubquery

Fields

expr: Box<Expression>

subquery: Box<SelectStatement>

negated: bool

Between

Fields

expr: Box<Expression>

low: Box<Expression>

high: Box<Expression>

negated: bool

Like

Fields

expr: Box<Expression>

pattern: Box<Expression>

negated: bool

IsNull

Fields

expr: Box<Expression>

negated: bool

Exists

Fields

subquery: Box<SelectStatement>

negated: bool

Subquery(Box<SelectStatement>)

Placeholder(usize)

Implementations

impl Expression

pub fn column(name: &str) -> Self

Create a column reference expression.

pub fn qualified_column(table: &str, column: &str) -> Self

Create a qualified column reference.

pub fn int(value: i64) -> Self

Create an integer literal.

pub fn string(value: &str) -> Self

Create a string literal.

pub fn boolean(value: bool) -> Self

Create a boolean literal.

pub fn null() -> Self

Create a NULL literal.

Trait Implementations

impl Clone for Expression

fn clone(&self) -> Expression

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Expression

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

Formats the value using the given formatter.

impl PartialEq for Expression

fn eq(&self, other: &Expression) -> 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 StructuralPartialEq for Expression