Struct sqlx::query::QueryScalar

#[must_use = "query must be executed to affect database"]pub struct QueryScalar<'q, DB, O, A> where
    DB: Database,  { /* fields omitted */ }

Raw SQL query with bind parameters, mapped to a concrete type using FromRow on (O,). Returned from query_scalar.

Implementations

impl<'q, DB, O> QueryScalar<'q, DB, O, <DB as HasArguments<'q>>::Arguments> where
    DB: Database, 

pub fn bind<T>(
    self,
    value: T
) -> QueryScalar<'q, DB, O, <DB as HasArguments<'q>>::Arguments> where
    T: 'q + Encode<'q, DB> + Type<DB> + Send, 

Bind a value for use with this SQL query.

See Query::bind.

impl<'q, DB, O, A> QueryScalar<'q, DB, O, A> where
    A: 'q + IntoArguments<'q, DB>,
    DB: Database,
    O: Send + Unpin,
    (O,): Send,
    (O,): Unpin,
    (O,): for<'r> FromRow<'r, <DB as Database>::Row>, 

pub fn fetch<'e, 'c, E>(
    self,
    executor: E
) -> Pin<Box<dyn Stream<Item = Result<O, Error>> + 'e + Send>> where
    'c: 'e,
    'q: 'e,
    A: 'e,
    DB: 'e,
    E: 'e + Executor<'c, Database = DB>,
    O: 'e, 

Execute the query and return the generated results as a stream.

pub fn fetch_many<'e, 'c, E>(
    self,
    executor: E
) -> Pin<Box<dyn Stream<Item = Result<Either<<DB as Database>::Done, O>, Error>> + 'e + Send>> where
    'c: 'e,
    'q: 'e,
    A: 'e,
    DB: 'e,
    E: 'e + Executor<'c, Database = DB>,
    O: 'e, 

Execute multiple queries and return the generated results as a stream from each query, in a stream.

pub async fn fetch_all<'e, 'c, E>(self, executor: E) -> Result<Vec<O>, Error> where
    'c: 'e,
    'q: 'e,
    A: 'e,
    DB: 'e,
    E: 'e + Executor<'c, Database = DB>,
    (O,): 'e, 

Execute the query and return all the generated results, collected into a Vec.

pub async fn fetch_one<'e, 'c, E>(self, executor: E) -> Result<O, Error> where
    'c: 'e,
    'q: 'e,
    A: 'e,
    DB: 'e,
    E: 'e + Executor<'c, Database = DB>,
    O: 'e, 

Execute the query and returns exactly one row.

pub async fn fetch_optional<'e, 'c, E>(
    self,
    executor: E
) -> Result<Option<O>, Error> where
    'c: 'e,
    'q: 'e,
    A: 'e,
    DB: 'e,
    E: 'e + Executor<'c, Database = DB>,
    O: 'e, 

Execute the query and returns at most one row.

Trait Implementations

impl<'q, DB, O, A> Execute<'q, DB> for QueryScalar<'q, DB, O, A> where
    A: Send + 'q + IntoArguments<'q, DB>,
    DB: Database,
    O: Send, 

fn sql(&self) -> &'q str

Gets the SQL that will be executed.

fn statement(&self) -> Option<&<DB as HasStatement<'q>>::Statement>

Gets the previously cached statement, if available.

fn take_arguments(&mut self) -> Option<<DB as HasArguments<'q>>::Arguments>

Returns the arguments to be bound against the query string.

fn persistent(&self) -> bool

Returns true if the statement should be cached.