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Mubelotix 2025-07-01 14:21:55 +02:00
parent 73dfeefc7c
commit 27cc357362
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@ -20,6 +20,158 @@ enum AscDescId {
Geo { field_ids: [u16; 2], target_point: [f64; 2], ascending: bool },
}
/// A [`SortedDocumentsIterator`] allows efficient access to a continuous range of sorted documents.
/// This is ideal in the context of paginated queries in which only a small number of documents are needed at a time.
/// Search operations will only be performed upon access.
pub enum SortedDocumentsIterator<'ctx> {
Leaf {
/// The exact number of documents remaining
size: usize,
values: Box<dyn Iterator<Item = DocumentId> + 'ctx>,
},
Branch {
/// The current child, got from the children iterator
current_child: Option<Box<SortedDocumentsIterator<'ctx>>>,
/// The exact number of documents remaining, excluding documents in the current child
next_children_size: usize,
/// Iterators to become the current child once it is exhausted
next_children:
Box<dyn Iterator<Item = crate::Result<SortedDocumentsIteratorBuilder<'ctx>>> + 'ctx>,
},
}
impl SortedDocumentsIterator<'_> {
/// Takes care of updating the current child if it is `None`, and also updates the size
fn update_current<'ctx>(
current_child: &mut Option<Box<SortedDocumentsIterator<'ctx>>>,
next_children_size: &mut usize,
next_children: &mut Box<
dyn Iterator<Item = crate::Result<SortedDocumentsIteratorBuilder<'ctx>>> + 'ctx,
>,
) -> crate::Result<()> {
if current_child.is_none() {
*current_child = match next_children.next() {
Some(Ok(builder)) => {
let next_child = Box::new(builder.build()?);
*next_children_size -= next_child.size_hint().0;
Some(next_child)
}
Some(Err(e)) => return Err(e),
None => return Ok(()),
};
}
Ok(())
}
}
impl Iterator for SortedDocumentsIterator<'_> {
type Item = crate::Result<DocumentId>;
/// Implementing the `nth` method allows for efficient access to the nth document in the sorted order.
/// It's used by `skip` internally.
/// The default implementation of `nth` would iterate over all children, which is inefficient for large datasets.
/// This implementation will jump over whole chunks of children until it gets close.
fn nth(&mut self, n: usize) -> Option<Self::Item> {
// If it's at the leaf level, just forward the call to the values iterator
let (current_child, next_children, next_children_size) = match self {
SortedDocumentsIterator::Leaf { values, size } => {
*size = size.saturating_sub(n);
return values.nth(n).map(Ok);
}
SortedDocumentsIterator::Branch {
current_child,
next_children,
next_children_size,
} => (current_child, next_children, next_children_size),
};
// Otherwise don't directly iterate over children, skip them if we know we will go further
let mut to_skip = n - 1;
while to_skip > 0 {
if let Err(e) = SortedDocumentsIterator::update_current(
current_child,
next_children_size,
next_children,
) {
return Some(Err(e));
}
let Some(inner) = current_child else {
return None; // No more inner iterators, everything has been consumed.
};
if to_skip >= inner.size_hint().0 {
// The current child isn't large enough to contain the nth element.
// Skip it and continue with the next one.
to_skip -= inner.size_hint().0;
*current_child = None;
continue;
} else {
// The current iterator is large enough, so we can forward the call to it.
return inner.nth(to_skip + 1);
}
}
self.next()
}
/// Iterators need to keep track of their size so that they can be skipped efficiently by the `nth` method.
fn size_hint(&self) -> (usize, Option<usize>) {
let size = match self {
SortedDocumentsIterator::Leaf { size, .. } => *size,
SortedDocumentsIterator::Branch {
next_children_size,
current_child: Some(current_child),
..
} => current_child.size_hint().0 + next_children_size,
SortedDocumentsIterator::Branch { next_children_size, current_child: None, .. } => {
*next_children_size
}
};
(size, Some(size))
}
fn next(&mut self) -> Option<Self::Item> {
match self {
SortedDocumentsIterator::Leaf { values, size } => {
let result = values.next().map(Ok);
if result.is_some() {
*size -= 1;
}
result
}
SortedDocumentsIterator::Branch {
current_child,
next_children_size,
next_children,
} => {
let mut result = None;
while result.is_none() {
// Ensure we have selected an iterator to work with
if let Err(e) = SortedDocumentsIterator::update_current(
current_child,
next_children_size,
next_children,
) {
return Some(Err(e));
}
let Some(inner) = current_child else {
return None;
};
result = inner.next();
// If the current iterator is exhausted, we need to try the next one
if result.is_none() {
*current_child = None;
}
}
result
}
}
}
}
/// Builder for a [`SortedDocumentsIterator`].
/// Most builders won't ever be built, because pagination will skip them.
pub struct SortedDocumentsIteratorBuilder<'ctx> {
@ -57,6 +209,7 @@ impl<'ctx> SortedDocumentsIteratorBuilder<'ctx> {
}
}
/// Builds a [`SortedDocumentsIterator`] based on the results of a facet sort.
fn build_facet(
self,
field_id: u16,
@ -108,6 +261,7 @@ impl<'ctx> SortedDocumentsIteratorBuilder<'ctx> {
})
}
/// Builds a [`SortedDocumentsIterator`] based on the (lazy) results of a geo sort.
fn build_geo(
self,
field_ids: [u16; 2],
@ -186,153 +340,6 @@ impl<'ctx> SortedDocumentsIteratorBuilder<'ctx> {
}
}
/// A [`SortedDocumentsIterator`] allows efficient access to a continuous range of sorted documents.
/// This is ideal in the context of paginated queries in which only a small number of documents are needed at a time.
/// Search operations will only be performed upon access.
pub enum SortedDocumentsIterator<'ctx> {
Leaf {
/// The exact number of documents remaining
size: usize,
values: Box<dyn Iterator<Item = DocumentId> + 'ctx>,
},
Branch {
/// The current child, got from the children iterator
current_child: Option<Box<SortedDocumentsIterator<'ctx>>>,
/// The exact number of documents remaining, excluding documents in the current child
next_children_size: usize,
/// Iterators to become the current child once it is exhausted
next_children:
Box<dyn Iterator<Item = crate::Result<SortedDocumentsIteratorBuilder<'ctx>>> + 'ctx>,
},
}
impl SortedDocumentsIterator<'_> {
/// Takes care of updating the current child if it is `None`, and also updates the size
fn update_current<'ctx>(
current_child: &mut Option<Box<SortedDocumentsIterator<'ctx>>>,
next_children_size: &mut usize,
next_children: &mut Box<
dyn Iterator<Item = crate::Result<SortedDocumentsIteratorBuilder<'ctx>>> + 'ctx,
>,
) -> crate::Result<()> {
if current_child.is_none() {
*current_child = match next_children.next() {
Some(Ok(builder)) => {
let next_child = Box::new(builder.build()?);
*next_children_size -= next_child.size_hint().0;
Some(next_child)
}
Some(Err(e)) => return Err(e),
None => return Ok(()),
};
}
Ok(())
}
}
impl Iterator for SortedDocumentsIterator<'_> {
type Item = crate::Result<DocumentId>;
fn nth(&mut self, n: usize) -> Option<Self::Item> {
// If it's at the leaf level, just forward the call to the values iterator
let (current_child, next_children, next_children_size) = match self {
SortedDocumentsIterator::Leaf { values, size } => {
*size = size.saturating_sub(n);
return values.nth(n).map(Ok);
}
SortedDocumentsIterator::Branch {
current_child,
next_children,
next_children_size,
} => (current_child, next_children, next_children_size),
};
// Otherwise don't directly iterate over children, skip them if we know we will go further
let mut to_skip = n - 1;
while to_skip > 0 {
if let Err(e) = SortedDocumentsIterator::update_current(
current_child,
next_children_size,
next_children,
) {
return Some(Err(e));
}
let Some(inner) = current_child else {
return None; // No more inner iterators, everything has been consumed.
};
if to_skip >= inner.size_hint().0 {
// The current child isn't large enough to contain the nth element.
// Skip it and continue with the next one.
to_skip -= inner.size_hint().0;
*current_child = None;
continue;
} else {
// The current iterator is large enough, so we can forward the call to it.
return inner.nth(to_skip + 1);
}
}
self.next()
}
fn size_hint(&self) -> (usize, Option<usize>) {
let size = match self {
SortedDocumentsIterator::Leaf { size, .. } => *size,
SortedDocumentsIterator::Branch {
next_children_size,
current_child: Some(current_child),
..
} => current_child.size_hint().0 + next_children_size,
SortedDocumentsIterator::Branch { next_children_size, current_child: None, .. } => {
*next_children_size
}
};
(size, Some(size))
}
fn next(&mut self) -> Option<Self::Item> {
match self {
SortedDocumentsIterator::Leaf { values, size } => {
let result = values.next().map(Ok);
if result.is_some() {
*size -= 1;
}
result
}
SortedDocumentsIterator::Branch {
current_child,
next_children_size,
next_children,
} => {
let mut result = None;
while result.is_none() {
// Ensure we have selected an iterator to work with
if let Err(e) = SortedDocumentsIterator::update_current(
current_child,
next_children_size,
next_children,
) {
return Some(Err(e));
}
let Some(inner) = current_child else {
return None;
};
result = inner.next();
// If the current iterator is exhausted, we need to try the next one
if result.is_none() {
*current_child = None;
}
}
result
}
}
}
}
/// A structure owning the data needed during the lifetime of a [`SortedDocumentsIterator`].
pub struct SortedDocuments<'ctx> {
index: &'ctx crate::Index,
@ -368,6 +375,7 @@ pub fn recursive_sort<'ctx>(
let sortable_fields: BTreeSet<_> = index.sortable_fields(rtxn)?.into_iter().collect();
let fields_ids_map = index.fields_ids_map(rtxn)?;
// Retrieve the field ids that are used for sorting
let mut fields = Vec::new();
let mut need_geo_candidates = false;
for asc_desc in sort {