Enum Expr 

pub enum Expr {
    Column {
        table: Option<String>,
        name: String,
        quote_style: QuoteStyle,
        table_quote_style: QuoteStyle,
    },
    Number(String),
    StringLiteral(String),
    Boolean(bool),
    Null,
    BinaryOp {
        left: Box<Expr>,
        op: BinaryOperator,
        right: Box<Expr>,
    },
    UnaryOp {
        op: UnaryOperator,
        expr: Box<Expr>,
    },
    Function {
        name: String,
        args: Vec<Expr>,
        distinct: bool,
        filter: Option<Box<Expr>>,
        over: Option<WindowSpec>,
    },
    Between {
        expr: Box<Expr>,
        low: Box<Expr>,
        high: Box<Expr>,
        negated: bool,
    },
    InList {
        expr: Box<Expr>,
        list: Vec<Expr>,
        negated: bool,
    },
    InSubquery {
        expr: Box<Expr>,
        subquery: Box<Statement>,
        negated: bool,
    },
    AnyOp {
        expr: Box<Expr>,
        op: BinaryOperator,
        right: Box<Expr>,
    },
    AllOp {
        expr: Box<Expr>,
        op: BinaryOperator,
        right: Box<Expr>,
    },
    IsNull {
        expr: Box<Expr>,
        negated: bool,
    },
    IsBool {
        expr: Box<Expr>,
        value: bool,
        negated: bool,
    },
    Like {
        expr: Box<Expr>,
        pattern: Box<Expr>,
        negated: bool,
        escape: Option<Box<Expr>>,
    },
    ILike {
        expr: Box<Expr>,
        pattern: Box<Expr>,
        negated: bool,
        escape: Option<Box<Expr>>,
    },
    Case {
        operand: Option<Box<Expr>>,
        when_clauses: Vec<(Expr, Expr)>,
        else_clause: Option<Box<Expr>>,
    },
    Nested(Box<Expr>),
    Wildcard,
    Subquery(Box<Statement>),
    Exists {
        subquery: Box<Statement>,
        negated: bool,
    },
    Cast {
        expr: Box<Expr>,
        data_type: DataType,
    },
    TryCast {
        expr: Box<Expr>,
        data_type: DataType,
    },
    Extract {
        field: DateTimeField,
        expr: Box<Expr>,
    },
    Interval {
        value: Box<Expr>,
        unit: Option<DateTimeField>,
    },
    ArrayLiteral(Vec<Expr>),
    Tuple(Vec<Expr>),
    Coalesce(Vec<Expr>),
    If {
        condition: Box<Expr>,
        true_val: Box<Expr>,
        false_val: Option<Box<Expr>>,
    },
    NullIf {
        expr: Box<Expr>,
        else: Box<Expr>,
    },
    Collate {
        expr: Box<Expr>,
        collation: String,
    },
    Parameter(String),
    TypeExpr(DataType),
    QualifiedWildcard {
        table: String,
    },
    Star,
    Alias {
        expr: Box<Expr>,
        name: String,
    },
    ArrayIndex {
        expr: Box<Expr>,
        index: Box<Expr>,
    },
    JsonAccess {
        expr: Box<Expr>,
        path: Box<Expr>,
        as_text: bool,
    },
    Lambda {
        params: Vec<String>,
        body: Box<Expr>,
    },
    Default,
    Cube {
        exprs: Vec<Expr>,
    },
    Rollup {
        exprs: Vec<Expr>,
    },
    GroupingSets {
        sets: Vec<Expr>,
    },
    TypedFunction {
        func: TypedFunction,
        filter: Option<Box<Expr>>,
        over: Option<WindowSpec>,
    },
    Commented {
        expr: Box<Expr>,
        comments: Vec<String>,
    },
}

An expression in SQL.

This enum is aligned with sqlglot’s Expression class hierarchy. Key additions over the basic implementation:

• Subquery, Exists, Cast, Extract, Window functions
• TypedString, Interval, Array/Struct constructors
• Postgres-style casting (::)

Variants

Column

A column reference, possibly qualified: [catalog.][schema.]table.column

Fields

table: Option<String>

name: String

quote_style: QuoteStyle

How the column name was quoted in the source SQL.

table_quote_style: QuoteStyle

How the table qualifier was quoted, if present.

Number(String)

A numeric literal.

StringLiteral(String)

A string literal.

Boolean(bool)

A boolean literal.

Null

NULL literal.

BinaryOp

A binary operation: left op right

Fields

left: Box<Expr>

op: BinaryOperator

right: Box<Expr>

UnaryOp

A unary operation: op expr

Fields

op: UnaryOperator

expr: Box<Expr>

Function

A function call: name(args...) with optional DISTINCT, ORDER BY, etc.

Fields

name: String

args: Vec<Expr>

distinct: bool

filter: Option<Box<Expr>>

FILTER (WHERE expr) clause on aggregate

over: Option<WindowSpec>

OVER window specification for window functions

Between

expr BETWEEN low AND high

Fields

expr: Box<Expr>

low: Box<Expr>

high: Box<Expr>

negated: bool

InList

expr IN (list...) or expr IN (subquery)

Fields

expr: Box<Expr>

list: Vec<Expr>

negated: bool

InSubquery

expr IN (SELECT ...)

Fields

expr: Box<Expr>

subquery: Box<Statement>

negated: bool

AnyOp

expr op ANY(subexpr) — PostgreSQL array/subquery comparison

Fields

expr: Box<Expr>

op: BinaryOperator

right: Box<Expr>

AllOp

expr op ALL(subexpr) — PostgreSQL array/subquery comparison

Fields

expr: Box<Expr>

op: BinaryOperator

right: Box<Expr>

IsNull

expr IS [NOT] NULL

Fields

expr: Box<Expr>

negated: bool

IsBool

expr IS [NOT] TRUE / expr IS [NOT] FALSE

Fields

expr: Box<Expr>

value: bool

negated: bool

Like

expr [NOT] LIKE pattern [ESCAPE escape_char]

Fields

expr: Box<Expr>

pattern: Box<Expr>

negated: bool

escape: Option<Box<Expr>>

ILike

expr [NOT] ILIKE pattern [ESCAPE escape_char] (case-insensitive LIKE)

Fields

expr: Box<Expr>

pattern: Box<Expr>

negated: bool

escape: Option<Box<Expr>>

Case

CASE [operand] WHEN ... THEN ... ELSE ... END

Fields

operand: Option<Box<Expr>>

when_clauses: Vec<(Expr, Expr)>

else_clause: Option<Box<Expr>>

Nested(Box<Expr>)

A parenthesized sub-expression.

Wildcard

A wildcard * used in contexts like COUNT(*).

Subquery(Box<Statement>)

A scalar subquery: (SELECT ...)

Exists

EXISTS (SELECT ...)

Fields

subquery: Box<Statement>

negated: bool

Cast

CAST(expr AS type) or expr::type (PostgreSQL)

Fields

expr: Box<Expr>

data_type: DataType

TryCast

TRY_CAST(expr AS type)

Fields

expr: Box<Expr>

data_type: DataType

Extract

EXTRACT(field FROM expr)

Fields

field: DateTimeField

expr: Box<Expr>

Interval

INTERVAL 'value' unit

Fields

value: Box<Expr>

unit: Option<DateTimeField>

ArrayLiteral(Vec<Expr>)

Array literal: ARRAY[1, 2, 3] or [1, 2, 3]

Tuple(Vec<Expr>)

Struct literal / row constructor: (1, 'a', true)

Coalesce(Vec<Expr>)

COALESCE(a, b, c)

If

IF(condition, true_val, false_val) (MySQL, BigQuery)

Fields

condition: Box<Expr>

true_val: Box<Expr>

false_val: Option<Box<Expr>>

NullIf

NULLIF(a, b)

Fields

expr: Box<Expr>

else: Box<Expr>

Collate

expr COLLATE collation

Fields

expr: Box<Expr>

collation: String

Parameter(String)

Parameter / placeholder: $1, ?, :name

TypeExpr(DataType)

A type expression used in DDL contexts or CAST

QualifiedWildcard

table.* in expression context

Fields

table: String

Star

Star expression *

Alias

Alias expression: expr AS name

Fields

expr: Box<Expr>

name: String

ArrayIndex

Array access: expr[index]

Fields

expr: Box<Expr>

index: Box<Expr>

JsonAccess

JSON access: expr->key or expr->>key

Fields

expr: Box<Expr>

path: Box<Expr>

as_text: bool

false = ->, true = ->>

Lambda

Lambda expression: x -> x + 1

Fields

params: Vec<String>

body: Box<Expr>

Default

DEFAULT keyword in INSERT/UPDATE contexts

Cube

CUBE(a, b, ...) in GROUP BY clause

Fields

exprs: Vec<Expr>

Rollup

ROLLUP(a, b, ...) in GROUP BY clause

Fields

exprs: Vec<Expr>

GroupingSets

GROUPING SETS ((a, b), (c), ...) in GROUP BY clause

Fields

sets: Vec<Expr>

TypedFunction

A typed function expression with semantic awareness. Enables per-function, per-dialect code generation and transpilation.

Fields

func: TypedFunction

filter: Option<Box<Expr>>

FILTER (WHERE expr) clause on aggregate

over: Option<WindowSpec>

OVER window specification for window functions

Commented

An expression with attached SQL comments. Wraps an inner expression so that comments survive transformations.

Fields

expr: Box<Expr>

comments: Vec<String>

Implementations

impl Expr

pub fn walk<F>(&self, visitor: &mut F)

where F: FnMut(&Expr) -> bool,

Recursively walk this expression tree, calling visitor on each node. If visitor returns false, children of that node are not visited.

pub fn find<F>(&self, predicate: &F) -> Option<&Expr>

where F: Fn(&Expr) -> bool,

Find the first expression matching the predicate.

pub fn find_all<F>(&self, predicate: &F) -> Vec<&Expr>

where F: Fn(&Expr) -> bool,

Find all expressions matching the predicate.

pub fn transform<F>(self, func: &F) -> Expr

where F: Fn(Expr) -> Expr,

Transform this expression tree by applying a function to each node. The function can return a new expression to replace the current one.

pub fn is_column(&self) -> bool

Check whether this expression is a column reference.

pub fn is_literal(&self) -> bool

Check whether this expression is a literal value (number, string, bool, null).

pub fn sql(&self) -> String

Get the SQL representation of this expression for display purposes. For full generation, use the Generator.

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<'de> Deserialize<'de> for Expr

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

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 Serialize for Expr

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for Expr