Trait Executor

pub trait Executor<'c>:
    Send
    + Debug
    + Sized {
    type Database: Database;

    // Required methods
    fn fetch_many<'e, 'q: 'e, E>(
        self,
        query: E,
    ) -> BoxStream<'e, Result<Either<<Self::Database as Database>::QueryResult, <Self::Database as Database>::Row>, Error>>
       where E: Execute<'q, Self::Database> + 'q,
             'c: 'e;
    fn fetch_optional<'e, 'q: 'e, E>(
        self,
        query: E,
    ) -> BoxFuture<'e, Result<Option<<Self::Database as Database>::Row>, Error>>
       where E: Execute<'q, Self::Database> + 'q,
             'c: 'e;
    fn prepare_with<'e, 'q: 'e>(
        self,
        sql: &'q str,
        parameters: &'e [<Self::Database as Database>::TypeInfo],
    ) -> BoxFuture<'e, Result<<Self::Database as HasStatement<'q>>::Statement, Error>>
       where 'c: 'e;

    // Provided methods
    fn execute<'e, 'q: 'e, E>(
        self,
        query: E,
    ) -> BoxFuture<'e, Result<<Self::Database as Database>::QueryResult, Error>>
       where E: Execute<'q, Self::Database> + 'q,
             'c: 'e { ... }
    fn execute_many<'e, 'q: 'e, E>(
        self,
        query: E,
    ) -> BoxStream<'e, Result<<Self::Database as Database>::QueryResult, Error>>
       where E: Execute<'q, Self::Database> + 'q,
             'c: 'e { ... }
    fn fetch<'e, 'q: 'e, E>(
        self,
        query: E,
    ) -> BoxStream<'e, Result<<Self::Database as Database>::Row, Error>>
       where E: Execute<'q, Self::Database> + 'q,
             'c: 'e { ... }
    fn fetch_all<'e, 'q: 'e, E>(
        self,
        query: E,
    ) -> BoxFuture<'e, Result<Vec<<Self::Database as Database>::Row>, Error>>
       where E: Execute<'q, Self::Database> + 'q,
             'c: 'e { ... }
    fn fetch_one<'e, 'q: 'e, E>(
        self,
        query: E,
    ) -> BoxFuture<'e, Result<<Self::Database as Database>::Row, Error>>
       where E: Execute<'q, Self::Database> + 'q,
             'c: 'e { ... }
    fn prepare<'e, 'q: 'e>(
        self,
        query: &'q str,
    ) -> BoxFuture<'e, Result<<Self::Database as HasStatement<'q>>::Statement, Error>>
       where 'c: 'e { ... }
}

A type that contains or can provide a database connection to use for executing queries against the database.

No guarantees are provided that successive queries run on the same physical database connection.

A Connection is an Executor that guarantees that successive queries are ran on the same physical database connection.

Implemented for the following:

• &Pool
• &mut PoolConnection
• &mut Connection

Required Associated Types

type Database: Database

Required Methods

fn fetch_many<'e, 'q: 'e, E>( self, query: E, ) -> BoxStream<'e, Result<Either<<Self::Database as Database>::QueryResult, <Self::Database as Database>::Row>, Error>>

where E: Execute<'q, Self::Database> + 'q, 'c: 'e,

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

fn fetch_optional<'e, 'q: 'e, E>( self, query: E, ) -> BoxFuture<'e, Result<Option<<Self::Database as Database>::Row>, Error>>

where E: Execute<'q, Self::Database> + 'q, 'c: 'e,

Execute the query and returns at most one row.

fn prepare_with<'e, 'q: 'e>( self, sql: &'q str, parameters: &'e [<Self::Database as Database>::TypeInfo], ) -> BoxFuture<'e, Result<<Self::Database as HasStatement<'q>>::Statement, Error>>

where 'c: 'e,

Prepare the SQL query, with parameter type information, to inspect the type information about its parameters and results.

Only some database drivers (PostgreSQL, MSSQL) can take advantage of this extra information to influence parameter type inference.

Provided Methods

fn execute<'e, 'q: 'e, E>( self, query: E, ) -> BoxFuture<'e, Result<<Self::Database as Database>::QueryResult, Error>>

where E: Execute<'q, Self::Database> + 'q, 'c: 'e,

Execute the query and return the total number of rows affected.

fn execute_many<'e, 'q: 'e, E>( self, query: E, ) -> BoxStream<'e, Result<<Self::Database as Database>::QueryResult, Error>>

where E: Execute<'q, Self::Database> + 'q, 'c: 'e,

Execute multiple queries and return the rows affected from each query, in a stream.

fn fetch<'e, 'q: 'e, E>( self, query: E, ) -> BoxStream<'e, Result<<Self::Database as Database>::Row, Error>>

where E: Execute<'q, Self::Database> + 'q, 'c: 'e,

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

fn fetch_all<'e, 'q: 'e, E>( self, query: E, ) -> BoxFuture<'e, Result<Vec<<Self::Database as Database>::Row>, Error>>

where E: Execute<'q, Self::Database> + 'q, 'c: 'e,

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

fn fetch_one<'e, 'q: 'e, E>( self, query: E, ) -> BoxFuture<'e, Result<<Self::Database as Database>::Row, Error>>

where E: Execute<'q, Self::Database> + 'q, 'c: 'e,

Execute the query and returns exactly one row.

fn prepare<'e, 'q: 'e>( self, query: &'q str, ) -> BoxFuture<'e, Result<<Self::Database as HasStatement<'q>>::Statement, Error>>

where 'c: 'e,

Prepare the SQL query to inspect the type information of its parameters and results.

Be advised that when using the query, query_as, or query_scalar functions, the query is transparently prepared and executed.

This explicit API is provided to allow access to the statement metadata available after it prepared but before the first row is returned.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors

impl<'c> Executor<'c> for &'c mut AnyConnection

type Database = Any

impl<'c> Executor<'c> for &'c mut MssqlConnection

Available on crate feature mssql only.

type Database = Mssql

impl<'c> Executor<'c> for &'c mut MySqlConnection

Available on crate feature mysql only.

type Database = MySql

impl<'c> Executor<'c> for &'c mut PoolConnection<Any>

type Database = Any

impl<'c> Executor<'c> for &'c mut PoolConnection<Mssql>

Available on crate feature mssql only.

type Database = Mssql

impl<'c> Executor<'c> for &'c mut PoolConnection<MySql>

Available on crate feature mysql only.

type Database = MySql

impl<'c> Executor<'c> for &'c mut PoolConnection<Postgres>

Available on crate feature postgres only.

type Database = Postgres

impl<'c> Executor<'c> for &'c mut PoolConnection<Sqlite>

Available on crate feature sqlite only.

type Database = Sqlite

impl<'c> Executor<'c> for &'c mut PgConnection

Available on crate feature postgres only.

type Database = Postgres

impl<'c> Executor<'c> for &'c mut PgListener

Available on crate feature postgres only.

type Database = Postgres

impl<'c> Executor<'c> for &'c mut SqliteConnection

Available on crate feature sqlite only.

type Database = Sqlite

impl<'c, 't> Executor<'t> for &'t mut Transaction<'c, Any>

type Database = Any

impl<'c, 't> Executor<'t> for &'t mut Transaction<'c, Mssql>

Available on crate feature mssql only.

type Database = Mssql

impl<'c, 't> Executor<'t> for &'t mut Transaction<'c, MySql>

Available on crate feature mysql only.

type Database = MySql

impl<'c, 't> Executor<'t> for &'t mut Transaction<'c, Postgres>

Available on crate feature postgres only.

type Database = Postgres

impl<'c, 't> Executor<'t> for &'t mut Transaction<'c, Sqlite>

Available on crate feature sqlite only.

type Database = Sqlite

impl<'p, DB: Database> Executor<'p> for &Pool<DB>

where for<'c> &'c mut DB::Connection: Executor<'c, Database = DB>,

type Database = DB