Struct Portal 

#[non_exhaustive]
pub struct Portal<S> {
    pub name: String,
    pub statement: Arc<StoredStatement<S>>,
    pub parameter_format: Format,
    pub parameters: Vec<Option<Bytes>>,
    pub result_column_format: Format,
    pub state: Arc<Mutex<PortalExecutionState>>,
}

Represent a prepared sql statement and its parameters bound by a Bind request.

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

name: String

statement: Arc<StoredStatement<S>>

parameter_format: Format

parameters: Vec<Option<Bytes>>

result_column_format: Format

state: Arc<Mutex<PortalExecutionState>>

Implementations

impl<S: Clone> Portal<S>

pub fn try_new( bind: &Bind, statement: Arc<StoredStatement<S>>, ) -> PgWireResult<Self>

Try to create portal from bind command and current client state

pub fn new_cursor(name: String, statement: Arc<StoredStatement<S>>) -> Self

Create a cursor-oriented portal with a stored statement.

The portal starts in Initial state. The first call to fetch() after start() will begin returning rows. Use start() to provide a QueryResponse before fetching.

pub fn parameter_len(&self) -> usize

Get number of parameters

pub fn parameter<'a, T>( &'a self, idx: usize, pg_type: &Type, ) -> PgWireResult<Option<T>>

where T: FromSqlOwned + FromSqlText<'a>,

Attempt to get parameter at given index as type T.

pub fn state(&self) -> Arc<Mutex<PortalExecutionState>>

Get a handle to the portal’s execution state.

pub async fn start(&self, response: QueryResponse)

Transition the portal from Initial to Suspended with the given query response.

This is called by the query handler after executing the portal’s statement, before calling fetch() to retrieve rows.

pub async fn fetch(&self, max_rows: usize) -> PgWireResult<FetchResult>

Fetch up to max_rows from a portal’s suspended state.

Returns a FetchResult containing the rows, the row schema, and whether the portal is still suspended (has more rows). When the underlying stream is exhausted, the portal transitions to Finished. When max_rows is 0, all remaining rows are fetched.

Returns an error if the portal is in Initial state (call start() first) or if the stream yields an error.

Trait Implementations

impl<S: Debug> Debug for Portal<S>

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

Formats the value using the given formatter.

impl<S: Default> Default for Portal<S>

fn default() -> Portal<S>

Returns the “default value” for a type.