Struct diesel::query_source::Alias

pub struct Alias<S> { /* private fields */ }

Represents an alias within diesel’s query builder

See alias! for more details.

Implementations

impl<S: AliasSource> Alias<S>

pub fn field<F>(&self, field: F) -> AliasedField<S, F> where
    F: Column<Table = S::Target>, 

Maps a single field of the source table in this alias

pub fn fields<Fields>(&self, fields: Fields) -> AliasedFields<S, Fields> where
    Fields: FieldAliasMapper<S>, 

Maps multiple fields of the source table in this alias (takes in tuples and some expressions)

Trait Implementations

impl<S, QS> AppearsInFromClause<QS> for Alias<S> where
    S: AliasSource,
    S::Target: AliasAppearsInFromClause<S, QS>, 

type Count = <<S as AliasSource>::Target as AliasAppearsInFromClause<S, QS>>::Count

How many times does Self appear in QS?

impl<S> AsQuery for Alias<S> where
    S: AliasSource,
    S::Target: AsQuery,
    Self: QuerySource,
    <Self as QuerySource>::DefaultSelection: ValidGrouping<()>, 

type SqlType = <<Alias<S> as QuerySource>::DefaultSelection as Expression>::SqlType

The SQL type of Self::Query

type Query = SelectStatement<FromClause<Alias<S>>, DefaultSelectClause<FromClause<Alias<S>>>, NoDistinctClause, NoWhereClause, NoOrderClause, LimitOffsetClause<NoLimitClause, NoOffsetClause>, NoGroupByClause, NoHavingClause, NoLockingClause>

What kind of query does this type represent?

fn as_query(self) -> Self::Query

Converts a type which semantically represents a SQL query into the actual query being executed. See the trait level docs for more.

impl<'a, S, DB> BoxedDsl<'a, DB> for Alias<S> where
    Alias<S>: QuerySource + AsQuery<Query = SelectStatement<FromClause<Alias<S>>>>,
    SelectStatement<FromClause<Alias<S>>>: BoxedDsl<'a, DB>,
    <Alias<S> as QuerySource>::DefaultSelection: Expression<SqlType = <Alias<S> as AsQuery>::SqlType> + ValidGrouping<()>,
    <Alias<S> as AsQuery>::SqlType: TypedExpressionType, 

type Output = <SelectStatement<FromClause<Alias<S>>, DefaultSelectClause<FromClause<Alias<S>>>, NoDistinctClause, NoWhereClause, NoOrderClause, LimitOffsetClause<NoLimitClause, NoOffsetClause>, NoGroupByClause, NoHavingClause, NoLockingClause> as BoxedDsl<'a, DB>>::Output

The return type of internal_into_boxed

fn internal_into_boxed(self) -> Self::Output

See the trait documentation.

impl<S: Clone> Clone for Alias<S>

fn clone(&self) -> Alias<S>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<S> CombineDsl for Alias<S> where
    S: AliasSource,
    S::Target: Table,
    Self: AsQuery, 

type Query = <Alias<S> as AsQuery>::Query

What kind of query does this type represent?

fn union<Rhs>(self, rhs: Rhs) -> Union<Self, Rhs> where
    Rhs: AsQuery<SqlType = <<Self as AsQuery>::Query as Query>::SqlType>, 

Combine two queries using a SQL UNION

fn union_all<Rhs>(self, rhs: Rhs) -> UnionAll<Self, Rhs> where
    Rhs: AsQuery<SqlType = <<Self as AsQuery>::Query as Query>::SqlType>, 

Combine two queries using a SQL UNION ALL

fn intersect<Rhs>(self, rhs: Rhs) -> Intersect<Self, Rhs> where
    Rhs: AsQuery<SqlType = <<Self as AsQuery>::Query as Query>::SqlType>, 

Combine two queries using a SQL INTERSECT

fn intersect_all<Rhs>(self, rhs: Rhs) -> IntersectAll<Self, Rhs> where
    Rhs: AsQuery<SqlType = <<Self as AsQuery>::Query as Query>::SqlType>, 

Combine two queries using a SQL INTERSECT ALL

fn except<Rhs>(self, rhs: Rhs) -> Except<Self, Rhs> where
    Rhs: AsQuery<SqlType = <<Self as AsQuery>::Query as Query>::SqlType>, 

Combine two queries using a SQL EXCEPT

fn except_all<Rhs>(self, rhs: Rhs) -> ExceptAll<Self, Rhs> where
    Rhs: AsQuery<SqlType = <<Self as AsQuery>::Query as Query>::SqlType>, 

Combine two queries using a SQL EXCEPT ALL

impl<S: Debug> Debug for Alias<S>

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

Formats the value using the given formatter.

impl<S: Default> Default for Alias<S>

fn default() -> Alias<S>

Returns the “default value” for a type.

impl<S, Selection> DistinctOnDsl<Selection> for Alias<S> where
    S: AliasSource,
    Selection: SelectableExpression<Self>,
    Selection::SqlType: SingleValue,
    Self: QuerySource + AsQuery<Query = SelectStatement<FromClause<Self>>>,
    SelectStatement<FromClause<Self>>: DistinctOnDsl<Selection>,
    <Self as QuerySource>::DefaultSelection: Expression<SqlType = <Self as AsQuery>::SqlType> + ValidGrouping<()>,
    <Self as AsQuery>::SqlType: TypedExpressionType, 

Available on crate feature postgres_backend only.

type Output = <SelectStatement<FromClause<Alias<S>>, DefaultSelectClause<FromClause<Alias<S>>>, NoDistinctClause, NoWhereClause, NoOrderClause, LimitOffsetClause<NoLimitClause, NoOffsetClause>, NoGroupByClause, NoHavingClause, NoLockingClause> as DistinctOnDsl<Selection>>::Output

The type returned by .distinct_on

fn distinct_on(self, selection: Selection) -> DistinctOn<Self, Selection>

See the trait documentation

impl<S, Predicate> FilterDsl<Predicate> for Alias<S> where
    Self: AsQuery,
    <Self as AsQuery>::Query: FilterDsl<Predicate>, 

type Output = <<Alias<S> as AsQuery>::Query as FilterDsl<Predicate>>::Output

The type returned by .filter.

fn filter(self, predicate: Predicate) -> Self::Output

See the trait documentation.

impl<S, PK> FindDsl<PK> for Alias<S> where
    S: AliasSource,
    S::Target: Table,
    <S::Target as Table>::PrimaryKey: FieldAliasMapper<S>,
    <<S::Target as Table>::PrimaryKey as FieldAliasMapper<S>>::Out: EqAll<PK>,
    Self: FilterDsl<<<<S::Target as Table>::PrimaryKey as FieldAliasMapper<S>>::Out as EqAll<PK>>::Output>, 

type Output = <Alias<S> as FilterDsl<<<<<S as AliasSource>::Target as Table>::PrimaryKey as FieldAliasMapper<S>>::Out as EqAll<PK>>::Output>>::Output

The type returned by .find.

fn find(self, id: PK) -> Self::Output

See the trait documentation.

impl<S, Expr> GroupByDsl<Expr> for Alias<S> where
    Expr: Expression,
    Self: QuerySource + AsQuery<Query = SelectStatement<FromClause<Self>>>,
    <Self as QuerySource>::DefaultSelection: Expression<SqlType = <Self as AsQuery>::SqlType> + ValidGrouping<()>,
    <Self as AsQuery>::SqlType: TypedExpressionType, 

type Output = <SelectStatement<FromClause<Alias<S>>, DefaultSelectClause<FromClause<Alias<S>>>, NoDistinctClause, NoWhereClause, NoOrderClause, LimitOffsetClause<NoLimitClause, NoOffsetClause>, NoGroupByClause, NoHavingClause, NoLockingClause> as GroupByDsl<Expr>>::Output

The type returned by .group_by

fn group_by(self, expr: Expr) -> GroupBy<Self, Expr>

See the trait documentation.

impl<S> LimitDsl for Alias<S> where
    Self: AsQuery,
    <Self as AsQuery>::Query: LimitDsl, 

type Output = <<Alias<S> as AsQuery>::Query as LimitDsl>::Output

The type returned by .limit

fn limit(self, limit: i64) -> Self::Output

See the trait documentation

impl<S, Lock> LockingDsl<Lock> for Alias<S> where
    Self: QuerySource + AsQuery<Query = SelectStatement<FromClause<Self>>>,
    <Self as QuerySource>::DefaultSelection: Expression<SqlType = <Self as AsQuery>::SqlType> + ValidGrouping<()>,
    <Self as AsQuery>::SqlType: TypedExpressionType, 

type Output = <SelectStatement<FromClause<Alias<S>>, DefaultSelectClause<FromClause<Alias<S>>>, NoDistinctClause, NoWhereClause, NoOrderClause, LimitOffsetClause<NoLimitClause, NoOffsetClause>, NoGroupByClause, NoHavingClause, NoLockingClause> as LockingDsl<Lock>>::Output

The type returned by set_lock. See dsl::ForUpdate and friends for convenient access to this type.

fn with_lock(self, lock: Lock) -> Self::Output

See the trait level documentation

impl<S> OffsetDsl for Alias<S> where
    Self: AsQuery,
    <Self as AsQuery>::Query: OffsetDsl, 

type Output = <<Alias<S> as AsQuery>::Query as OffsetDsl>::Output

The type returned by .offset.

fn offset(self, offset: i64) -> Self::Output

See the trait documentation

impl<S, Predicate> OrFilterDsl<Predicate> for Alias<S> where
    Self: AsQuery,
    <Self as AsQuery>::Query: OrFilterDsl<Predicate>, 

type Output = <<Alias<S> as AsQuery>::Query as OrFilterDsl<Predicate>>::Output

The type returned by .filter.

fn or_filter(self, predicate: Predicate) -> Self::Output

See the trait documentation.

impl<S, Expr> OrderDsl<Expr> for Alias<S> where
    Expr: Expression,
    Self: AsQuery,
    <Self as AsQuery>::Query: OrderDsl<Expr>, 

type Output = <<Alias<S> as AsQuery>::Query as OrderDsl<Expr>>::Output

The type returned by .order.

fn order(self, expr: Expr) -> Self::Output

See the trait documentation.

impl<S: AliasSource> QueryDsl for Alias<S>

fn distinct(self) -> Distinct<Self> where
    Self: DistinctDsl, 

Adds the DISTINCT keyword to a query.

fn distinct_on<Expr>(self, expr: Expr) -> DistinctOn<Self, Expr> where
    Self: DistinctOnDsl<Expr>, 

Available on crate feature postgres only.

Adds the DISTINCT ON clause to a query.

fn select<Selection>(self, selection: Selection) -> Select<Self, Selection> where
    Selection: Expression,
    Self: SelectDsl<Selection>, 

Adds a SELECT clause to the query.

fn count(self) -> Select<Self, CountStar> where
    Self: SelectDsl<CountStar>, 

Get the count of a query. This is equivalent to .select(count_star())

fn inner_join<Rhs>(self, rhs: Rhs) -> InnerJoin<Self, Rhs> where
    Self: JoinWithImplicitOnClause<Rhs, Inner>, 

Join two tables using a SQL INNER JOIN.

fn left_outer_join<Rhs>(self, rhs: Rhs) -> LeftJoin<Self, Rhs> where
    Self: JoinWithImplicitOnClause<Rhs, LeftOuter>, 

Join two tables using a SQL LEFT OUTER JOIN.

fn left_join<Rhs>(self, rhs: Rhs) -> LeftJoin<Self, Rhs> where
    Self: JoinWithImplicitOnClause<Rhs, LeftOuter>, 

Alias for left_outer_join.

fn filter<Predicate>(self, predicate: Predicate) -> Filter<Self, Predicate> where
    Self: FilterDsl<Predicate>, 

Adds to the WHERE clause of a query.

fn or_filter<Predicate>(self, predicate: Predicate) -> OrFilter<Self, Predicate> where
    Self: OrFilterDsl<Predicate>, 

Adds to the WHERE clause of a query using OR

fn find<PK>(self, id: PK) -> Find<Self, PK> where
    Self: FindDsl<PK>, 

Attempts to find a single record from the given table by primary key.

fn order<Expr>(self, expr: Expr) -> Order<Self, Expr> where
    Expr: Expression,
    Self: OrderDsl<Expr>, 

Sets the order clause of a query.

fn order_by<Expr>(self, expr: Expr) -> Order<Self, Expr> where
    Expr: Expression,
    Self: OrderDsl<Expr>, 

Alias for order

fn then_order_by<Order>(self, order: Order) -> ThenOrderBy<Self, Order> where
    Self: ThenOrderDsl<Order>, 

Appends to the ORDER BY clause of this SQL query.

fn limit(self, limit: i64) -> Limit<Self> where
    Self: LimitDsl, 

Sets the limit clause of the query.

fn offset(self, offset: i64) -> Offset<Self> where
    Self: OffsetDsl, 

Sets the offset clause of the query.

fn group_by<GB>(self, group_by: GB) -> GroupBy<Self, GB> where
    GB: Expression,
    Self: GroupByDsl<GB>, 

Sets the group by clause of a query.

fn having<Predicate>(self, predicate: Predicate) -> Having<Self, Predicate> where
    Self: HavingDsl<Predicate>, 

Adds to the HAVING clause of a query.

fn for_update(self) -> ForUpdate<Self> where
    Self: LockingDsl<ForUpdate>, 

Adds FOR UPDATE to the end of the select statement.

fn for_no_key_update(self) -> ForNoKeyUpdate<Self> where
    Self: LockingDsl<ForNoKeyUpdate>, 

Adds FOR NO KEY UPDATE to the end of the select statement.

fn for_share(self) -> ForShare<Self> where
    Self: LockingDsl<ForShare>, 

Adds FOR SHARE to the end of the select statement.

fn for_key_share(self) -> ForKeyShare<Self> where
    Self: LockingDsl<ForKeyShare>, 

Adds FOR KEY SHARE to the end of the select statement.

fn skip_locked(self) -> SkipLocked<Self> where
    Self: ModifyLockDsl<SkipLocked>, 

Adds SKIP LOCKED to the end of a FOR UPDATE clause.

fn no_wait(self) -> NoWait<Self> where
    Self: ModifyLockDsl<NoWait>, 

Adds NOWAIT to the end of a FOR UPDATE clause.

fn into_boxed<'a, DB>(self) -> IntoBoxed<'a, Self, DB> where
    DB: Backend,
    Self: BoxedDsl<'a, DB>, 

Boxes the pieces of a query into a single type.

fn single_value(self) -> SingleValue<Self> where
    Self: SingleValueDsl, 

Wraps this select statement in parenthesis, allowing it to be used as an expression.

fn nullable(self) -> NullableSelect<Self> where
    Self: SelectNullableDsl, 

Coerce the SQL type of the select clause to it’s nullable equivalent.

impl<S> QueryId for Alias<S> where
    Self: 'static,
    S: AliasSource,
    S::Target: QueryId, 

type QueryId = Alias<S>

A type which uniquely represents Self in a SQL query.

const HAS_STATIC_QUERY_ID: bool = ::HAS_STATIC_QUERY_ID

Can the SQL generated by Self be uniquely identified by its type?

fn query_id() -> Option<TypeId>

Returns the type id of Self::QueryId if Self::HAS_STATIC_QUERY_ID. Returns None otherwise.

impl<S> QuerySource for Alias<S> where
    Self: Clone,
    S: AliasSource,
    S::Target: QuerySource,
    <S::Target as QuerySource>::DefaultSelection: FieldAliasMapper<S>,
    <<S::Target as QuerySource>::DefaultSelection as FieldAliasMapper<S>>::Out: SelectableExpression<Self>, 

type FromClause = Alias<S>

The type returned by from_clause

type DefaultSelection = <<<S as AliasSource>::Target as QuerySource>::DefaultSelection as FieldAliasMapper<S>>::Out

The type returned by default_selection

fn from_clause(&self) -> Self::FromClause

The actual FROM clause of this type. This is typically only called in QueryFragment implementations.

fn default_selection(&self) -> Self::DefaultSelection

The default select clause of this type, which should be used if no select clause was explicitly specified. This should always be a tuple of all the desired columns, not star

impl<S: AliasSource, Conn> RunQueryDsl<Conn> for Alias<S>

fn execute(self, conn: &mut Conn) -> QueryResult<usize> where
    Conn: Connection,
    Self: ExecuteDsl<Conn>, 

Executes the given command, returning the number of rows affected.

fn load<'query, U>(self, conn: &mut Conn) -> QueryResult<Vec<U>> where
    Self: LoadQuery<'query, Conn, U>, 

Executes the given query, returning a Vec with the returned rows.

fn load_iter<'conn, 'query: 'conn, U>(
    self,
    conn: &'conn mut Conn
) -> QueryResult<LoadIter<'conn, 'query, Self, Conn, U>> where
    U: 'conn,
    Self: LoadQuery<'query, Conn, U> + 'conn, 

Executes the given query, returning an Iterator with the returned rows.

fn get_result<'query, U>(self, conn: &mut Conn) -> QueryResult<U> where
    Self: LoadQuery<'query, Conn, U>, 

Runs the command, and returns the affected row.

fn get_results<'query, U>(self, conn: &mut Conn) -> QueryResult<Vec<U>> where
    Self: LoadQuery<'query, Conn, U>, 

Runs the command, returning an Vec with the affected rows.

fn first<'query, U>(self, conn: &mut Conn) -> QueryResult<U> where
    Self: LimitDsl,
    Limit<Self>: LoadQuery<'query, Conn, U>, 

Attempts to load a single record.

impl<S, Selection> SelectDsl<Selection> for Alias<S> where
    Selection: Expression,
    Self: AsQuery,
    <Self as AsQuery>::Query: SelectDsl<Selection>, 

type Output = <<Alias<S> as AsQuery>::Query as SelectDsl<Selection>>::Output

The type returned by .select

fn select(self, selection: Selection) -> Self::Output

See the trait documentation

impl<S, Expr> ThenOrderDsl<Expr> for Alias<S> where
    Expr: Expression,
    Self: AsQuery,
    <Self as AsQuery>::Query: ThenOrderDsl<Expr>, 

type Output = <<Alias<S> as AsQuery>::Query as ThenOrderDsl<Expr>>::Output

The type returned by .then_order_by.

fn then_order_by(self, expr: Expr) -> Self::Output

See the trait documentation.

impl<S: Copy> Copy for Alias<S>

impl<S2, S> JoinTo<Alias<S2>> for Alias<S> where
    S2: AliasSource,
    S: AliasSource + Default,
    S::Target: JoinTo<Alias<S2>>,
    <S::Target as JoinTo<Alias<S2>>>::OnClause: FieldAliasMapper<S>, 

impl<T, S> JoinTo<T> for Alias<S> where
    T: Table,
    S: AliasSource + Default,
    S::Target: JoinTo<T>,
    <S::Target as JoinTo<T>>::OnClause: FieldAliasMapper<S>, 

impl<S, C> SelectableExpression<Alias<S>> for AliasedField<S, C> where
    S: AliasSource,
    C: Column<Table = S::Target>,
    Self: AppearsOnTable<Alias<S>>,