Struct QueryPager

pub struct QueryPager { /* private fields */ }

An intermediate object that allows to construct a stream over a query that is asynchronously paged in the background.

Before the results can be processed in a convenient way, the QueryPager needs to be cast into a typed stream. This is done by use of rows_stream() method. As the method is generic over the target type, the turbofish syntax can come in handy there, e.g. query_pager.rows_stream::<(i32, String, Uuid)>().

Implementations

impl QueryPager

pub fn type_check<'frame, 'metadata, RowT: DeserializeRow<'frame, 'metadata>>( &self, ) -> Result<(), TypeCheckError>

Type-checks the iterator against given type.

This is automatically called upon transforming QueryPager into TypedRowStream.

pub fn rows_stream<RowT: 'static + for<'frame, 'metadata> DeserializeRow<'frame, 'metadata>>( self, ) -> Result<TypedRowStream<RowT>, TypeCheckError>

Casts the iterator to a given row type, enabling Stream’ed operations on rows, which deserialize them on-the-fly to that given type. It only allows deserializing owned types, because Stream is not lending. Begins with performing type check.

pub fn tracing_ids(&self) -> &[Uuid]

If tracing was enabled returns tracing ids of all finished page queries

pub fn column_specs(&self) -> ColumnSpecs<'_, '_>

Returns specification of row columns

Trait Implementations

impl Debug for QueryPager

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

Formats the value using the given formatter.