Struct ExprInSubquery 

pub struct ExprInSubquery {
    pub expr: Box<Expr>,
    pub query: Box<Query>,
    pub negated: bool,
    pub relation_key: bool,
}

Tests whether a value is in the results of a subquery.

Returns true if expr matches any row returned by query, or the opposite when negated is set. The flag makes NOT IN a predicate in its own right rather than the negation of IN: statement normalization attaches variant guards to the predicate before expanding the negated form to not(in_subquery(..)), so the guards end up outside the negation.

Examples

in_subquery(x, select(...))      // returns `true` if `x` is in the subquery results
not_in_subquery(x, select(...))  // returns `true` if `x` is not in the subquery results

Fields

expr: Box<Expr>

The value to search for.

query: Box<Query>

The subquery to search within.

negated: bool

Whether the check is NOT IN.

relation_key: bool

Whether this compares relation keys rather than application values.

Relation lifting sets this when it rewrites a relation membership into a key comparison. A relation key identifies a row only when it is present, so an absent key on either side never matches. A value membership compares the values themselves.

Temporary: this marks the one membership that needs two-valued results before application predicates have their own representation. Remove it once https://github.com/tokio-rs/toasty/pull/1251 lands, since that lowers lifted relation memberships as application predicates.

Trait Implementations

impl Clone for ExprInSubquery

fn clone(&self) -> ExprInSubquery

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for ExprInSubquery

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

Formats the value using the given formatter.

impl From<ExprInSubquery> for Expr

fn from(value: ExprInSubquery) -> Expr

Converts to this type from the input type.

impl Node for ExprInSubquery

fn visit<V>(&self, visit: V)

where V: Visit,

Traverses this node with an immutable visitor.

fn visit_mut<V>(&mut self, visit: V)

where V: VisitMut,

Traverses this node with a mutable visitor.

impl PartialEq for ExprInSubquery

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