Struct Filter 

pub struct Filter(/* private fields */);

A typed condition on its way to a WHERE.

What a Column comparison produces. It is three things at once, which is what lets typed filters mix with Layer 1 anywhere:

• a Mod on anything with a WHERE (HasWhere) — so it sits directly in users::table().query((users::age().gte(21), …)), and equally in a raw dialect statement’s mod tuple;
• an IntoExpr — so it drops into any expression slot (select::where_, a join’s on, a CASE arm);
• a Chain — so .and(…), .or(…) and every other Layer 1 operator keep working after the typed comparison started the chain.

Implementations

impl Filter

pub fn new(condition: impl IntoExpr) -> Filter

Wrap any expression — a raw &str fragment included — as a filter, so hand-written SQL rides the same WHERE path the typed comparisons use.

Trait Implementations

impl Chain for Filter

fn from_expr(e: Expr) -> Filter

Wrap a finished expression back into the chain type.

fn step(self, f: impl FnOnce(Expr) -> Expr) -> Self

One chain step: build a node from this expression, apply the parenthesisation rule, and return a chain again.

fn op(self, op: &'static str, rhs: impl IntoExpr) -> Self

An arbitrary infix operator: self op rhs.

fn eq(self, rhs: impl IntoExpr) -> Self

self = rhs.

fn ne(self, rhs: impl IntoExpr) -> Self

self <> rhs. The standard spelling, which every dialect accepts.

fn lt(self, rhs: impl IntoExpr) -> Self

self < rhs.

fn lte(self, rhs: impl IntoExpr) -> Self

self <= rhs.

fn gt(self, rhs: impl IntoExpr) -> Self

self > rhs.

fn gte(self, rhs: impl IntoExpr) -> Self

self >= rhs.

fn in_(self, vals: impl IntoExprList) -> Self

self IN (a, b, c).

fn not_in(self, vals: impl IntoExprList) -> Self

self NOT IN (a, b, c).

fn is_null(self) -> Self

self IS NULL.

fn is_not_null(self) -> Self

self IS NOT NULL.

fn is_distinct_from(self, rhs: impl IntoExpr) -> Self

self IS DISTINCT FROM rhs.

fn is_not_distinct_from(self, rhs: impl IntoExpr) -> Self

self IS NOT DISTINCT FROM rhs.

fn between(self, a: impl IntoExpr, b: impl IntoExpr) -> Self

self BETWEEN a AND b.

fn not_between(self, a: impl IntoExpr, b: impl IntoExpr) -> Self

self NOT BETWEEN a AND b.

fn like(self, rhs: impl IntoExpr) -> Self

self LIKE rhs.

fn concat(self, others: impl IntoExprList) -> Self

self || a || b — string concatenation.

fn and(self, others: impl IntoExprList) -> Self

self AND a AND b.

fn or(self, others: impl IntoExprList) -> Self

self OR a OR b.

fn plus(self, rhs: impl IntoExpr) -> Self

self + rhs.

fn minus(self, rhs: impl IntoExpr) -> Self

self - rhs.

fn as_(self, alias: impl IntoIdent) -> Expr

self AS "alias".

impl Clone for Filter

fn clone(&self) -> Filter

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Filter

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

Formats the value using the given formatter.

impl IntoExpr for Filter

fn into_expr(self) -> Expr

Perform the conversion.

impl IntoExprList for Filter

fn into_expr_list(self) -> Vec<Expr>

Perform the conversion.

impl<Q: HasWhere> Mod<Q> for Filter

Appends to the WHERE clause; several filters AND together, matching Where’s own contract.

fn apply(self, q: &mut Q)

Apply this modification to q.