Struct Update 

pub struct Update<D, T: Table> { /* private fields */ }

Implementations

impl<D, T: Table> Update<D, T>

pub fn correlated<S, InnerSel>( &self, source: S, selection: InnerSel, ) -> Select<D, Cons<TableSlot<S::Table, NotNull>, WrittenTable<T>>, InnerSel, WrittenTable<T>>

where S: JoinSource<D>,

A correlated subquery over the table this statement writes — the same EXISTS a SELECT builds with Select::correlated, against the one-table scope a write statement has.

pub fn filter<C: Condition<D, WrittenTable<T>, Idxs>, Idxs>( self, cond: C, ) -> Self

pub fn filter_all( self, conds: impl IntoIterator<Item = Predicate<D, WrittenTable<T>>>, ) -> Self

AND-folds a runtime-length collection of discharged conditions, the same way Select::filter_all does — a PATCH narrows its rows by however many criteria the request carried.

impl<D, T: Table> Update<D, T>

pub fn set_to<C, V, Idxs>(self, column: Column<C>, value: V) -> Self

where C: ColumnKey<Table = T> + Writable, V: IntoExpr, V::Sql: AssignsTo<C::Sql>, WrittenTable<T>: Superset<V::Req, Idxs>,

One more assignment, appended to whatever .set(..) already assigned — see Assignments::set_to.

Trait Implementations

impl<D: Dialect, T: Table> Statement for Update<D, T>

type Dialect = D

type Table = T

fn to_sql(&self, _dialect: Self::Dialect) -> (String, Vec<Value>)

The dialect is an argument for the reason Select::to_sql’s is.

fn returning<Sel, Idx>(self, sel: Sel) -> Returning<Self, Sel>

where Self: Sized, Self::Dialect: SupportsReturning, Sel: Selection<WrittenTable<Self::Table>, Idx>,

RETURNING, on whichever of the three this is — the clause is the same clause. A distinct type rather than Self with a flag set: the execution layer needs Sel’s concrete type to know what to decode a returned row into, and an optional field would erase it.