Enum Conn 

pub enum Conn<'a> {
    Pooled(PoolConnection<Postgres>),
    Borrowed(&'a mut PgConnection),
}

A connection for the length of one call. It derefs to PgConnection.

Variants

Pooled(PoolConnection<Postgres>)

Taken from the pool, and given back when dropped.

Borrowed(&'a mut PgConnection)

The caller’s.

Methods from Deref<Target = PgConnection>

pub fn server_version_num(&self) -> Option<u32>

the version number of the server in libpq format

pub async fn copy_in_raw( &mut self, statement: &str, ) -> Result<PgCopyIn<&mut PgConnection>, Error>

Issue a COPY FROM STDIN statement and transition the connection to streaming data to Postgres. This is a more efficient way to import data into Postgres as compared to INSERT but requires one of a few specific data formats (text/CSV/binary).

If statement is anything other than a COPY ... FROM STDIN ... command, an error is returned.

Command examples and accepted formats for COPY data are shown here: https://www.postgresql.org/docs/current/sql-copy.html

Note

PgCopyIn::finish or PgCopyIn::abort must be called when finished or the connection will return an error the next time it is used.

pub async fn copy_out_raw<'c>( &'c mut self, statement: &str, ) -> Result<Pin<Box<dyn Stream<Item = Result<Bytes, Error>> + Send + 'c>>, Error>

Issue a COPY TO STDOUT statement and transition the connection to streaming data from Postgres. This is a more efficient way to export data from Postgres but arrives in chunks of one of a few data formats (text/CSV/binary).

If statement is anything other than a COPY ... TO STDOUT ... command, an error is returned.

Note that once this process has begun, unless you read the stream to completion, it can only be canceled in two ways:

1. by closing the connection, or:
2. by using another connection to kill the server process that is sending the data as shown in this StackOverflow answer.

If you don’t read the stream to completion, the next time the connection is used it will need to read and discard all the remaining queued data, which could take some time.

Command examples and accepted formats for COPY data are shown here: https://www.postgresql.org/docs/current/sql-copy.html

Trait Implementations

impl Deref for Conn<'_>

type Target = PgConnection

The resulting type after dereferencing.

fn deref(&self) -> &PgConnection

Dereferences the value.

impl DerefMut for Conn<'_>

fn deref_mut(&mut self) -> &mut PgConnection

Mutably dereferences the value.