Enum Expr 

#[non_exhaustive]
pub enum Expr {
    Field(String),
    Literal(LiteralValue),
    FuncCall {
        name: String,
        args: Vec<Expr>,
    },
    BinaryOp {
        op: ArithmeticOp,
        left: Box<Expr>,
        right: Box<Expr>,
    },
    If {
        condition: Condition,
        then_expr: Box<Expr>,
        else_expr: Box<Expr>,
    },
    Case {
        branches: Vec<(Condition, Expr)>,
        default: Option<Box<Expr>>,
    },
    Window {
        func: WindowFunc,
        over: WindowSpec,
    },
}

Expression used in select clauses and function arguments.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Field(String)

필드 참조: name

Literal(LiteralValue)

리터럴 값: 42, "hello", true

FuncCall

함수 호출: upper(name), round(price, 2), upper(trim(name))

Fields

name: String

args: Vec<Expr>

BinaryOp

이항 산술 연산: amount * quantity, first_name + " " + last_name

Fields

op: ArithmeticOp

left: Box<Expr>

right: Box<Expr>

If

조건 표현식: if(condition, then_expr, else_expr)

Fields

condition: Condition

then_expr: Box<Expr>

else_expr: Box<Expr>

Case

CASE 표현식: case when cond1 then expr1 [when cond2 then expr2]* [else expr] end

Fields

branches: Vec<(Condition, Expr)>

default: Option<Box<Expr>>

Window

윈도우 함수: func(...) over (partition by ... order by ...)

Fields

func: WindowFunc

over: WindowSpec

Trait Implementations

impl Clone for Expr

fn clone(&self) -> Expr

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Expr

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

Formats the value using the given formatter.

impl PartialEq for Expr

fn eq(&self, other: &Expr) -> 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 Expr