Struct mz_expr::row::collection::SortedRowCollectionIter

pub struct SortedRowCollectionIter {
    collection: SortedRowCollection,
    row_idx: usize,
    diff_idx: usize,
    limit: Option<usize>,
    offset: usize,
    projection: Option<Vec<usize>>,
    projection_buf: (DatumVec, Row),
}

Fields

collection: SortedRowCollection

Collection we’re iterating over.

row_idx: usize

Index for the row we’re currently referencing.

diff_idx: usize

Number of diffs we’ve emitted for the current row.

limit: Option<usize>

Maximum number of rows this iterator will yield.

offset: usize

Number of rows we’re offset by.

Note: We eagerly apply an offset, but we track it here so we can accurately report RowIterator::count.

projection: Option<Vec<usize>>

Columns to underlying rows to include.

projection_buf: (DatumVec, Row)

Allocations that we reuse for every iteration to project columns.

Implementations

impl SortedRowCollectionIter

pub fn into_inner(self) -> SortedRowCollection

Returns the inner SortedRowCollection.

pub fn apply_offset(self, offset: usize) -> SortedRowCollectionIter

Immediately applies an offset to this iterator.

pub fn with_limit(self, limit: usize) -> SortedRowCollectionIter

Sets the limit for this iterator.

pub fn with_projection(self, projection: Vec<usize>) -> SortedRowCollectionIter

Specify the columns that should be yielded.

fn advance_by( collection: &SortedRowCollection, row_idx: &mut usize, diff_idx: &mut usize, count: usize, )

Helper method for implementing RowIterator.

Advances the internal pointers by the specified amount.

fn project<'a>( projection: Option<&[usize]>, row: &'a RowRef, datum_buf: &'a mut DatumVec, row_buf: &'a mut Row, ) -> &'a RowRef

Helper method for implementing RowIterator.

Projects columns for the provided row.

Trait Implementations

impl Clone for SortedRowCollectionIter

fn clone(&self) -> SortedRowCollectionIter

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for SortedRowCollectionIter

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

Formats the value using the given formatter.

impl RowIterator for SortedRowCollectionIter

fn next(&mut self) -> Option<&RowRef>

Returns the next RowRef advancing the iterator.

fn peek(&mut self) -> Option<&RowRef>

Returns the next RowRef without advancing the iterator.

fn count(&self) -> usize

The total number of Rows this iterator could ever yield.

fn map<T, F>(self, f: F) -> MappedRowIterator<Self, F>

where Self: Sized, F: FnMut(&RowRef) -> T,

Maps the returned RowRefs from this RowIterator.