Enum Expr 

pub enum Expr {
    Field(String),
    QualifiedField {
        qualifier: String,
        field: String,
    },
    Literal(Literal),
    Param(String),
    BinaryOp(Box<Expr>, BinOp, Box<Expr>),
    UnaryOp(UnaryOp, Box<Expr>),
    FunctionCall(AggFunc, Box<Expr>),
    ScalarFunc(ScalarFn, Vec<Expr>),
    Coalesce(Box<Expr>, Box<Expr>),
    InList {
        expr: Box<Expr>,
        list: Vec<Expr>,
        negated: bool,
    },
    InSubquery {
        expr: Box<Expr>,
        subquery: Box<QueryExpr>,
        negated: bool,
    },
    ExistsSubquery {
        subquery: Box<QueryExpr>,
        negated: bool,
    },
    Case {
        whens: Vec<(Box<Expr>, Box<Expr>)>,
        else_expr: Option<Box<Expr>>,
    },
    Window {
        function: WindowFunc,
        args: Vec<Expr>,
        partition_by: Vec<String>,
        order_by: Vec<OrderKey>,
    },
    Cast(Box<Expr>, CastType),
    Null,
}

Expressions.

Variants

Field(String)

QualifiedField

A table-qualified field reference: table.field or alias.field. Used by join queries to disambiguate columns that appear in multiple sources. The single-table read path never emits this variant, so existing fast paths keep matching Expr::Field unchanged.

Fields

qualifier: String

field: String

Literal(Literal)

Param(String)

BinaryOp(Box<Expr>, BinOp, Box<Expr>)

UnaryOp(UnaryOp, Box<Expr>)

FunctionCall(AggFunc, Box<Expr>)

ScalarFunc(ScalarFn, Vec<Expr>)

Scalar (non-aggregate) function call.

Coalesce(Box<Expr>, Box<Expr>)

InList

expr in (val1, val2, ...) or expr not in (val1, val2, ...)

Fields

expr: Box<Expr>

list: Vec<Expr>

negated: bool

InSubquery

expr [not] in (subquery) — the subquery is a full QueryExpr that produces a single column.

Fields

expr: Box<Expr>

subquery: Box<QueryExpr>

negated: bool

ExistsSubquery

[not] exists (subquery) — the subquery is a full QueryExpr. Currently uncorrelated only: the executor runs the subquery once before the scan loop and replaces this node with a Bool literal.

Fields

subquery: Box<QueryExpr>

negated: bool

Case

CASE WHEN … THEN … [ELSE …] END

Fields

whens: Vec<(Box<Expr>, Box<Expr>)>

else_expr: Option<Box<Expr>>

Window

Window function: func(args) over (partition ... order ...)

Fields

function: WindowFunc

args: Vec<Expr>

partition_by: Vec<String>

order_by: Vec<OrderKey>

Cast(Box<Expr>, CastType)

Type cast: cast(expr, "int") or cast(expr, "str") etc.

Null

The null literal — produces Value::Empty.

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