Remove the unused distance

This reverts commit 7a4b6c065482f988b01298642f4c18775503f92f.

.github/workflows/sdks-tests.yml

@@ -16,8 +16,23 @@ env:
   MEILI_NO_ANALYTICS: 'true'
 
 jobs:
+  define-docker-image:
+    runs-on: ubuntu-latest
+    outputs:
+      docker-image: ${{ steps.define-image.outputs.docker-image }}
+    steps:
+      - uses: actions/checkout@v3
+      - name: Define the Docker image we need to use
+        id: define-image
+        run: |
+          event=${{ github.event.action }}
+          echo "docker-image=nightly" >> $GITHUB_OUTPUT
+          if [[ $event == 'workflow_dispatch' ]]; then
+            echo "docker-image=${{ github.event.inputs.docker_image }}" >> $GITHUB_OUTPUT
+          fi
 
   meilisearch-js-tests:
+    needs: define-docker-image
     name: JS SDK tests
     runs-on: ubuntu-latest
     services:
@@ -52,6 +67,7 @@ jobs:
         run: yarn test:env:browser
 
   instant-meilisearch-tests:
+    needs: define-docker-image
     name: instant-meilisearch tests
     runs-on: ubuntu-latest
     services:
@@ -78,6 +94,7 @@ jobs:
         run: yarn build
 
   meilisearch-php-tests:
+    needs: define-docker-image
     name: PHP SDK tests
     runs-on: ubuntu-latest
     services:
@@ -108,6 +125,7 @@ jobs:
           composer remove --dev guzzlehttp/guzzle http-interop/http-factory-guzzle
 
   meilisearch-python-tests:
+    needs: define-docker-image
     name: Python SDK tests
     runs-on: ubuntu-latest
     services:
@@ -132,6 +150,7 @@ jobs:
         run: pipenv run pytest
 
   meilisearch-go-tests:
+    needs: define-docker-image
     name: Go SDK tests
     runs-on: ubuntu-latest
     services:
@@ -161,6 +180,7 @@ jobs:
         run: go test -v ./...
 
   meilisearch-ruby-tests:
+    needs: define-docker-image
     name: Ruby SDK tests
     runs-on: ubuntu-latest
     services:
@@ -185,6 +205,7 @@ jobs:
         run: bundle exec rspec
 
   meilisearch-rust-tests:
+    needs: define-docker-image
     name: Rust SDK tests
     runs-on: ubuntu-latest
     services:

Cargo.lock

@@ -1207,6 +1207,12 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "doc-comment"
+version = "0.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fea41bba32d969b513997752735605054bc0dfa92b4c56bf1189f2e174be7a10"
+
 [[package]]
 name = "dump"
 version = "1.2.0"
@@ -1763,6 +1769,15 @@ dependencies = [
  "byteorder",
 ]
 
+[[package]]
+name = "hashbrown"
+version = "0.11.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ab5ef0d4909ef3724cc8cce6ccc8572c5c817592e9285f5464f8e86f8bd3726e"
+dependencies = [
+ "ahash 0.7.6",
+]
+
 [[package]]
 name = "hashbrown"
 version = "0.12.3"
@@ -1864,6 +1879,22 @@ dependencies = [
  "digest",
 ]
 
+[[package]]
+name = "hnsw"
+version = "0.11.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2b9740ebf8769ec4ad6762cc951ba18f39bba6dfbc2fbbe46285f7539af79752"
+dependencies = [
+ "ahash 0.7.6",
+ "hashbrown 0.11.2",
+ "libm",
+ "num-traits",
+ "rand_core",
+ "serde",
+ "smallvec",
+ "space",
+]
+
 [[package]]
 name = "http"
 version = "0.2.9"
@@ -1994,7 +2025,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bd070e393353796e801d209ad339e89596eb4c8d430d18ede6a1cced8fafbd99"
 dependencies = [
  "autocfg",
- "hashbrown",
+ "hashbrown 0.12.3",
  "serde",
 ]
 
@@ -2086,7 +2117,7 @@ checksum = "37228e06c75842d1097432d94d02f37fe3ebfca9791c2e8fef6e9db17ed128c1"
 dependencies = [
  "cedarwood",
  "fxhash",
- "hashbrown",
+ "hashbrown 0.12.3",
  "lazy_static",
  "phf",
  "phf_codegen",
@@ -2715,6 +2746,7 @@ dependencies = [
  "bimap",
  "bincode",
  "bstr",
+ "bytemuck",
  "byteorder",
  "charabia",
  "concat-arrays",
@@ -2730,6 +2762,7 @@ dependencies = [
  "geoutils",
  "grenad",
  "heed",
+ "hnsw",
  "insta",
  "itertools",
  "json-depth-checker",
@@ -2744,6 +2777,7 @@ dependencies = [
  "once_cell",
  "ordered-float",
  "rand",
+ "rand_pcg",
  "rayon",
  "roaring",
  "rstar",
@@ -2753,6 +2787,7 @@ dependencies = [
  "smallstr",
  "smallvec",
  "smartstring",
+ "space",
  "tempfile",
  "thiserror",
  "time",
@@ -3327,6 +3362,16 @@ dependencies = [
  "getrandom",
 ]
 
+[[package]]
+name = "rand_pcg"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "59cad018caf63deb318e5a4586d99a24424a364f40f1e5778c29aca23f4fc73e"
+dependencies = [
+ "rand_core",
+ "serde",
+]
+
 [[package]]
 name = "rayon"
 version = "1.7.0"
@@ -3764,6 +3809,9 @@ name = "smallvec"
 version = "1.10.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a507befe795404456341dfab10cef66ead4c041f62b8b11bbb92bffe5d0953e0"
+dependencies = [
+ "serde",
+]
 
 [[package]]
 name = "smartstring"
@@ -3786,6 +3834,16 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "space"
+version = "0.17.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c5ab9701ae895386d13db622abf411989deff7109b13b46b6173bb4ce5c1d123"
+dependencies = [
+ "doc-comment",
+ "num-traits",
+]
+
 [[package]]
 name = "spin"
 version = "0.5.2"
@@ -4433,7 +4491,7 @@ version = "0.16.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9c531a2dc4c462b833788be2c07eef4e621d0e9edbd55bf280cc164c1c1aa043"
 dependencies = [
- "hashbrown",
+ "hashbrown 0.12.3",
  "once_cell",
 ]
 

meilisearch-types/src/error.rs

@@ -217,6 +217,7 @@ InvalidDocumentFields                 , InvalidRequest       , BAD_REQUEST ;
 MissingDocumentFilter                 , InvalidRequest       , BAD_REQUEST ;
 InvalidDocumentFilter                 , InvalidRequest       , BAD_REQUEST ;
 InvalidDocumentGeoField               , InvalidRequest       , BAD_REQUEST ;
+InvalidVectorDimensions               , InvalidRequest       , BAD_REQUEST ;
 InvalidDocumentId                     , InvalidRequest       , BAD_REQUEST ;
 InvalidDocumentLimit                  , InvalidRequest       , BAD_REQUEST ;
 InvalidDocumentOffset                 , InvalidRequest       , BAD_REQUEST ;
@@ -236,13 +237,10 @@ InvalidSearchHighlightPreTag          , InvalidRequest       , BAD_REQUEST ;
 InvalidSearchHitsPerPage              , InvalidRequest       , BAD_REQUEST ;
 InvalidSearchLimit                    , InvalidRequest       , BAD_REQUEST ;
 InvalidSearchMatchingStrategy         , InvalidRequest       , BAD_REQUEST ;
-InvalidMultiSearchMergeStrategy       , InvalidRequest       , BAD_REQUEST ;
 InvalidSearchOffset                   , InvalidRequest       , BAD_REQUEST ;
 InvalidSearchPage                     , InvalidRequest       , BAD_REQUEST ;
 InvalidSearchQ                        , InvalidRequest       , BAD_REQUEST ;
 InvalidSearchShowMatchesPosition      , InvalidRequest       , BAD_REQUEST ;
-InvalidSearchShowRankingScore         , InvalidRequest       , BAD_REQUEST ;
-InvalidSearchShowRankingScoreDetails  , InvalidRequest       , BAD_REQUEST ;
 InvalidSearchSort                     , InvalidRequest       , BAD_REQUEST ;
 InvalidSettingsDisplayedAttributes    , InvalidRequest       , BAD_REQUEST ;
 InvalidSettingsDistinctAttribute      , InvalidRequest       , BAD_REQUEST ;
@@ -335,6 +333,7 @@ impl ErrorCode for milli::Error {
                     UserError::InvalidSortableAttribute { .. } => Code::InvalidSearchSort,
                     UserError::CriterionError(_) => Code::InvalidSettingsRankingRules,
                     UserError::InvalidGeoField { .. } => Code::InvalidDocumentGeoField,
+                    UserError::InvalidVectorDimensions { .. } => Code::InvalidVectorDimensions,
                     UserError::SortError(_) => Code::InvalidSearchSort,
                     UserError::InvalidMinTypoWordLenSetting(_, _) => {
                         Code::InvalidSettingsTypoTolerance

meilisearch/src/routes/indexes/search.rs

@@ -34,6 +34,8 @@ pub fn configure(cfg: &mut web::ServiceConfig) {
 pub struct SearchQueryGet {
     #[deserr(default, error = DeserrQueryParamError<InvalidSearchQ>)]
     q: Option<String>,
+    #[deserr(default, error = DeserrQueryParamError<InvalidSearchQ>)]
+    vector: Option<Vec<f32>>,
     #[deserr(default = Param(DEFAULT_SEARCH_OFFSET()), error = DeserrQueryParamError<InvalidSearchOffset>)]
     offset: Param<usize>,
     #[deserr(default = Param(DEFAULT_SEARCH_LIMIT()), error = DeserrQueryParamError<InvalidSearchLimit>)]
@@ -56,10 +58,6 @@ pub struct SearchQueryGet {
     sort: Option<String>,
     #[deserr(default, error = DeserrQueryParamError<InvalidSearchShowMatchesPosition>)]
     show_matches_position: Param<bool>,
-    #[deserr(default, error = DeserrQueryParamError<InvalidSearchShowRankingScore>)]
-    show_ranking_score: Param<bool>,
-    #[deserr(default, error = DeserrQueryParamError<InvalidSearchShowRankingScoreDetails>)]
-    show_ranking_score_details: Param<bool>,
     #[deserr(default, error = DeserrQueryParamError<InvalidSearchFacets>)]
     facets: Option<CS<String>>,
     #[deserr( default = DEFAULT_HIGHLIGHT_PRE_TAG(), error = DeserrQueryParamError<InvalidSearchHighlightPreTag>)]
@@ -84,6 +82,7 @@ impl From<SearchQueryGet> for SearchQuery {
 
         Self {
             q: other.q,
+            vector: other.vector,
             offset: other.offset.0,
             limit: other.limit.0,
             page: other.page.as_deref().copied(),
@@ -95,8 +94,6 @@ impl From<SearchQueryGet> for SearchQuery {
             filter,
             sort: other.sort.map(|attr| fix_sort_query_parameters(&attr)),
             show_matches_position: other.show_matches_position.0,
-            show_ranking_score: other.show_ranking_score.0,
-            show_ranking_score_details: other.show_ranking_score_details.0,
             facets: other.facets.map(|o| o.into_iter().collect()),
             highlight_pre_tag: other.highlight_pre_tag,
             highlight_post_tag: other.highlight_post_tag,

meilisearch/src/routes/multi_search.rs

@@ -1,26 +1,20 @@
-use std::collections::HashMap;
-
 use actix_http::StatusCode;
 use actix_web::web::{self, Data};
 use actix_web::{HttpRequest, HttpResponse};
 use deserr::actix_web::AwebJson;
-use deserr::Deserr;
 use index_scheduler::IndexScheduler;
 use log::debug;
 use meilisearch_types::deserr::DeserrJsonError;
-use meilisearch_types::error::deserr_codes::InvalidMultiSearchMergeStrategy;
 use meilisearch_types::error::ResponseError;
 use meilisearch_types::keys::actions;
-use meilisearch_types::milli::score_details::NotComparable;
 use serde::Serialize;
 
 use crate::analytics::{Analytics, MultiSearchAggregator};
 use crate::extractors::authentication::policies::ActionPolicy;
 use crate::extractors::authentication::{AuthenticationError, GuardedData};
 use crate::extractors::sequential_extractor::SeqHandler;
-use crate::milli::score_details::ScoreDetails;
 use crate::search::{
-    add_search_rules, perform_search, SearchHit, SearchQueryWithIndex, SearchResultWithIndex,
+    add_search_rules, perform_search, SearchQueryWithIndex, SearchResultWithIndex,
 };
 
 pub fn configure(cfg: &mut web::ServiceConfig) {
@@ -29,34 +23,13 @@ pub fn configure(cfg: &mut web::ServiceConfig) {
 
 #[derive(Serialize)]
 struct SearchResults {
-    #[serde(skip_serializing_if = "Option::is_none")]
-    aggregate_hits: Option<Vec<SearchHitWithIndex>>,
     results: Vec<SearchResultWithIndex>,
 }
 
-#[derive(Serialize, Debug, Clone, PartialEq)]
-#[serde(rename_all = "camelCase")]
-struct SearchHitWithIndex {
-    pub index_uid: String,
-    #[serde(flatten)]
-    pub hit: SearchHit,
-}
-
 #[derive(Debug, deserr::Deserr)]
 #[deserr(error = DeserrJsonError, rename_all = camelCase, deny_unknown_fields)]
 pub struct SearchQueries {
     queries: Vec<SearchQueryWithIndex>,
-    #[deserr(default, error = DeserrJsonError<InvalidMultiSearchMergeStrategy>, default)]
-    merge_strategy: MergeStrategy,
-}
-
-#[derive(Debug, Clone, PartialEq, Eq, Deserr, Default)]
-#[deserr(rename_all = camelCase)]
-pub enum MergeStrategy {
-    #[default]
-    None,
-    ByNormalizedScore,
-    ByScoreDetails,
 }
 
 pub async fn multi_search_with_post(
@@ -65,13 +38,7 @@ pub async fn multi_search_with_post(
     req: HttpRequest,
     analytics: web::Data<dyn Analytics>,
 ) -> Result<HttpResponse, ResponseError> {
-    let SearchQueries { queries, merge_strategy } = params.into_inner();
-    // FIXME: REMOVE UNWRAP
-    let max_hits = queries
-        .iter()
-        .map(|SearchQueryWithIndex { limit, hits_per_page, .. }| hits_per_page.unwrap_or(*limit))
-        .max()
-        .unwrap();
+    let queries = params.into_inner().queries;
 
     let mut multi_aggregate = MultiSearchAggregator::from_queries(&queries, &req);
 
@@ -137,117 +104,7 @@ pub async fn multi_search_with_post(
 
     debug!("returns: {:?}", search_results);
 
-    let aggregate_hits = match merge_strategy {
-        MergeStrategy::None => None,
-        MergeStrategy::ByScoreDetails => Some(merge_by_score_details(&search_results, max_hits)),
-        MergeStrategy::ByNormalizedScore => {
-            Some(merge_by_normalized_score(&search_results, max_hits))
-        }
-    };
-
-    Ok(HttpResponse::Ok().json(SearchResults { aggregate_hits, results: search_results }))
-}
-
-fn merge_by_score_details(
-    search_results: &[SearchResultWithIndex],
-    max_hits: usize,
-) -> Vec<SearchHitWithIndex> {
-    let mut iterators: Vec<_> = search_results
-        .iter()
-        .filter_map(|SearchResultWithIndex { index_uid, result }| {
-            let mut it = result.hits.iter();
-            let next = it.next()?;
-            Some((index_uid, it, next))
-        })
-        .collect();
-
-    let mut hits = Vec::with_capacity(max_hits);
-
-    let mut inconsistent_indexes = HashMap::new();
-
-    for _ in 0..max_hits {
-        iterators.sort_by(|(left_uid, _, left_hit), (right_uid, _, right_hit)| {
-            let error = match ScoreDetails::partial_cmp_iter(
-                left_hit.ranking_score_raw.iter(),
-                right_hit.ranking_score_raw.iter(),
-            ) {
-                Ok(ord) => return ord,
-                Err(NotComparable(incomparable_index)) => incomparable_index,
-            };
-            inconsistent_indexes.entry((left_uid.to_owned(), right_uid.to_owned())).or_insert_with(
-                || {
-                    format!(
-                        "Detailed score {:?} is not comparable with {:?}: (left: {:#?}, right: {:#?})",
-                        left_hit.ranking_score_raw.get(error),
-                        right_hit.ranking_score_raw.get(error),
-                        left_hit.ranking_score_raw,
-                        right_hit.ranking_score_raw
-                    )
-                },
-            );
-            std::cmp::Ordering::Less
-        });
-        if !inconsistent_indexes.is_empty() {
-            let mut s = String::new();
-            for ((left_uid, right_uid), error) in &inconsistent_indexes {
-                use std::fmt::Write;
-                writeln!(s, "Indexes {} and {} are inconsistent: {}", left_uid, right_uid, error)
-                    .unwrap();
-            }
-            // Replace panic with proper error
-            panic!("{}", s);
-        }
-
-        let Some((index_uid, it, next)) = iterators.last_mut()
-        else {
-            break;
-        };
-
-        let hit = SearchHitWithIndex { index_uid: index_uid.clone(), hit: next.clone() };
-        if let Some(next_hit) = it.next() {
-            *next = next_hit;
-        } else {
-            iterators.pop();
-        }
-        hits.push(hit);
-    }
-    hits
-}
-
-fn merge_by_normalized_score(
-    search_results: &[SearchResultWithIndex],
-    max_hits: usize,
-) -> Vec<SearchHitWithIndex> {
-    let mut iterators: Vec<_> = search_results
-        .iter()
-        .filter_map(|SearchResultWithIndex { index_uid, result }| {
-            let mut it = result.hits.iter();
-            let next = it.next()?;
-            Some((index_uid, it, next))
-        })
-        .collect();
-
-    let mut hits = Vec::with_capacity(max_hits);
-
-    for _ in 0..max_hits {
-        iterators.sort_by_key(|(_, _, hit)| {
-            ScoreDetails::global_score_linear_scale(hit.ranking_score_raw.iter())
-        });
-
-        let Some((index_uid, it, next)) = iterators.last_mut()
-        else {
-            break;
-        };
-
-        let hit = SearchHitWithIndex { index_uid: index_uid.clone(), hit: next.clone() };
-        if let Some(next_hit) = it.next() {
-            *next = next_hit;
-        } else {
-            iterators.pop();
-        }
-        hits.push(hit);
-    }
-    hits
+    Ok(HttpResponse::Ok().json(SearchResults { results: search_results }))
 }
 
 /// Local `Result` extension trait to avoid `map_err` boilerplate.

meilisearch/src/search.rs

@@ -9,7 +9,6 @@ use meilisearch_auth::IndexSearchRules;
 use meilisearch_types::deserr::DeserrJsonError;
 use meilisearch_types::error::deserr_codes::*;
 use meilisearch_types::index_uid::IndexUid;
-use meilisearch_types::milli::score_details::ScoreDetails;
 use meilisearch_types::settings::DEFAULT_PAGINATION_MAX_TOTAL_HITS;
 use meilisearch_types::{milli, Document};
 use milli::tokenizer::TokenizerBuilder;
@@ -32,11 +31,13 @@ pub const DEFAULT_CROP_MARKER: fn() -> String = || "…".to_string();
 pub const DEFAULT_HIGHLIGHT_PRE_TAG: fn() -> String = || "<em>".to_string();
 pub const DEFAULT_HIGHLIGHT_POST_TAG: fn() -> String = || "</em>".to_string();
 
-#[derive(Debug, Clone, Default, PartialEq, Eq, Deserr)]
+#[derive(Debug, Clone, Default, PartialEq, Deserr)]
 #[deserr(error = DeserrJsonError, rename_all = camelCase, deny_unknown_fields)]
 pub struct SearchQuery {
     #[deserr(default, error = DeserrJsonError<InvalidSearchQ>)]
     pub q: Option<String>,
+    #[deserr(default, error = DeserrJsonError<InvalidSearchQ>)]
+    pub vector: Option<Vec<f32>>,
     #[deserr(default = DEFAULT_SEARCH_OFFSET(), error = DeserrJsonError<InvalidSearchOffset>)]
     pub offset: usize,
     #[deserr(default = DEFAULT_SEARCH_LIMIT(), error = DeserrJsonError<InvalidSearchLimit>)]
@@ -55,10 +56,6 @@ pub struct SearchQuery {
     pub attributes_to_highlight: Option<HashSet<String>>,
     #[deserr(default, error = DeserrJsonError<InvalidSearchShowMatchesPosition>, default)]
     pub show_matches_position: bool,
-    #[deserr(default, error = DeserrJsonError<InvalidSearchShowRankingScore>, default)]
-    pub show_ranking_score: bool,
-    #[deserr(default, error = DeserrJsonError<InvalidSearchShowRankingScoreDetails>, default)]
-    pub show_ranking_score_details: bool,
     #[deserr(default, error = DeserrJsonError<InvalidSearchFilter>)]
     pub filter: Option<Value>,
     #[deserr(default, error = DeserrJsonError<InvalidSearchSort>)]
@@ -85,13 +82,15 @@ impl SearchQuery {
 // This struct contains the fields of `SearchQuery` inline.
 // This is because neither deserr nor serde support `flatten` when using `deny_unknown_fields.
 // The `From<SearchQueryWithIndex>` implementation ensures both structs remain up to date.
-#[derive(Debug, Clone, PartialEq, Eq, Deserr)]
+#[derive(Debug, Clone, PartialEq, Deserr)]
 #[deserr(error = DeserrJsonError, rename_all = camelCase, deny_unknown_fields)]
 pub struct SearchQueryWithIndex {
     #[deserr(error = DeserrJsonError<InvalidIndexUid>, missing_field_error = DeserrJsonError::missing_index_uid)]
     pub index_uid: IndexUid,
     #[deserr(default, error = DeserrJsonError<InvalidSearchQ>)]
     pub q: Option<String>,
+    #[deserr(default, error = DeserrJsonError<InvalidSearchQ>)]
+    pub vector: Option<Vec<f32>>,
     #[deserr(default = DEFAULT_SEARCH_OFFSET(), error = DeserrJsonError<InvalidSearchOffset>)]
     pub offset: usize,
     #[deserr(default = DEFAULT_SEARCH_LIMIT(), error = DeserrJsonError<InvalidSearchLimit>)]
@@ -108,10 +107,6 @@ pub struct SearchQueryWithIndex {
     pub crop_length: usize,
     #[deserr(default, error = DeserrJsonError<InvalidSearchAttributesToHighlight>)]
     pub attributes_to_highlight: Option<HashSet<String>>,
-    #[deserr(default, error = DeserrJsonError<InvalidSearchShowRankingScore>, default)]
-    pub show_ranking_score: bool,
-    #[deserr(default, error = DeserrJsonError<InvalidSearchShowRankingScoreDetails>, default)]
-    pub show_ranking_score_details: bool,
     #[deserr(default, error = DeserrJsonError<InvalidSearchShowMatchesPosition>, default)]
     pub show_matches_position: bool,
     #[deserr(default, error = DeserrJsonError<InvalidSearchFilter>)]
@@ -135,6 +130,7 @@ impl SearchQueryWithIndex {
         let SearchQueryWithIndex {
             index_uid,
             q,
+            vector,
             offset,
             limit,
             page,
@@ -143,8 +139,6 @@ impl SearchQueryWithIndex {
             attributes_to_crop,
             crop_length,
             attributes_to_highlight,
-            show_ranking_score,
-            show_ranking_score_details,
             show_matches_position,
             filter,
             sort,
@@ -158,6 +152,7 @@ impl SearchQueryWithIndex {
             index_uid,
             SearchQuery {
                 q,
+                vector,
                 offset,
                 limit,
                 page,
@@ -166,8 +161,6 @@ impl SearchQueryWithIndex {
                 attributes_to_crop,
                 crop_length,
                 attributes_to_highlight,
-                show_ranking_score,
-                show_ranking_score_details,
                 show_matches_position,
                 filter,
                 sort,
@@ -207,7 +200,7 @@ impl From<MatchingStrategy> for TermsMatchingStrategy {
     }
 }
 
-#[derive(Debug, Clone, Serialize, PartialEq)]
+#[derive(Debug, Clone, Serialize, PartialEq, Eq)]
 pub struct SearchHit {
     #[serde(flatten)]
     pub document: Document,
@@ -215,12 +208,6 @@ pub struct SearchHit {
     pub formatted: Document,
     #[serde(rename = "_matchesPosition", skip_serializing_if = "Option::is_none")]
     pub matches_position: Option<MatchesPosition>,
-    #[serde(rename = "_rankingScore", skip_serializing_if = "Option::is_none")]
-    pub ranking_score: Option<u64>,
-    #[serde(rename = "_rankingScoreDetails", skip_serializing_if = "Option::is_none")]
-    pub ranking_score_details: Option<serde_json::Map<String, serde_json::Value>>,
-    #[serde(skip)]
-    pub ranking_score_raw: Vec<ScoreDetails>,
 }
 
 #[derive(Serialize, Debug, Clone, PartialEq)]
@@ -289,6 +276,10 @@ pub fn perform_search(
 
     let mut search = index.search(&rtxn);
 
+    if let Some(ref vector) = query.vector {
+        search.vector(vector.clone());
+    }
+
     if let Some(ref query) = query.q {
         search.query(query);
     }
@@ -339,8 +330,7 @@ pub fn perform_search(
         search.sort_criteria(sort);
     }
 
-    let milli::SearchResult { documents_ids, matching_words, candidates, document_scores, .. } =
-        search.execute()?;
+    let milli::SearchResult { documents_ids, matching_words, candidates, .. } = search.execute()?;
 
     let fields_ids_map = index.fields_ids_map(&rtxn).unwrap();
 
@@ -412,7 +402,7 @@ pub fn perform_search(
 
     let documents_iter = index.documents(&rtxn, documents_ids)?;
 
-    for ((_id, obkv), score) in documents_iter.into_iter().zip(document_scores.into_iter()) {
+    for (_id, obkv) in documents_iter {
         // First generate a document with all the displayed fields
         let displayed_document = make_document(&displayed_ids, &fields_ids_map, obkv)?;
 
@@ -436,19 +426,7 @@ pub fn perform_search(
             insert_geo_distance(sort, &mut document);
         }
 
-        let ranking_score =
-            query.show_ranking_score.then(|| ScoreDetails::global_score_linear_scale(score.iter()));
-        let ranking_score_details =
-            query.show_ranking_score_details.then(|| ScoreDetails::to_json_map(score.iter()));
-
-        let hit = SearchHit {
-            document,
-            formatted,
-            matches_position,
-            ranking_score_details,
-            ranking_score,
-            ranking_score_raw: score,
-        };
+        let hit = SearchHit { document, formatted, matches_position };
         documents.push(hit);
     }
 

meilisearch/tests/search/formatted.rs

@@ -1,4 +1,3 @@
-use insta::{allow_duplicates, assert_json_snapshot};
 use serde_json::json;
 
 use super::*;
@@ -19,45 +18,30 @@ async fn formatted_contain_wildcard() {
         |response, code|
         {
             assert_eq!(code, 200, "{}", response);
-            allow_duplicates! {
-              assert_json_snapshot!(response["hits"][0],
-                    { "._rankingScore" => "[score]" },
-                    @r###"
-              {
-                "_formatted": {
-                  "id": "852",
-                  "cattos": "<em>pésti</em>"
-                },
-                "_matchesPosition": {
-                  "cattos": [
-                    {
-                      "start": 0,
-                      "length": 5
-                    }
-                  ]
-                },
-                "_rankingScore": "[score]"
-              }
-              "###);
-            }
-    }
+            assert_eq!(
+                response["hits"][0],
+                json!({
+                    "_formatted": {
+                        "id": "852",
+                        "cattos": "<em>pésti</em>",
+                    },
+                    "_matchesPosition": {"cattos": [{"start": 0, "length": 5}]},
+                })
+            );
+        }
     )
     .await;
 
     index
         .search(json!({ "q": "pésti", "attributesToRetrieve": ["*"] }), |response, code| {
             assert_eq!(code, 200, "{}", response);
-            allow_duplicates! {
-                assert_json_snapshot!(response["hits"][0],
-                { "._rankingScore" => "[score]" },
-                @r###"
-                {
-                  "id": 852,
-                  "cattos": "pésti",
-                  "_rankingScore": "[score]"
-                }
-                "###)
-            }
+            assert_eq!(
+                response["hits"][0],
+                json!({
+                    "id": 852,
+                    "cattos": "pésti",
+                })
+            );
         })
         .await;
 
@@ -66,30 +50,20 @@ async fn formatted_contain_wildcard() {
             json!({ "q": "pésti", "attributesToRetrieve": ["*"], "attributesToHighlight": ["id"], "showMatchesPosition": true }),
             |response, code| {
                 assert_eq!(code, 200, "{}", response);
-                allow_duplicates! {
-                  assert_json_snapshot!(response["hits"][0],
-                 { "._rankingScore" => "[score]" },
-                 @r###"
-                  {
-                    "id": 852,
-                    "cattos": "pésti",
-                    "_formatted": {
-                      "id": "852",
-                      "cattos": "pésti"
-                    },
-                    "_matchesPosition": {
-                      "cattos": [
-                        {
-                          "start": 0,
-                          "length": 5
-                        }
-                      ]
-                    },
-                    "_rankingScore": "[score]"
-                  }
-                  "###)
-             }
-        })
+                assert_eq!(
+                    response["hits"][0],
+                    json!({
+                        "id": 852,
+                        "cattos": "pésti",
+                        "_formatted": {
+                            "id": "852",
+                            "cattos": "pésti",
+                        },
+                        "_matchesPosition": {"cattos": [{"start": 0, "length": 5}]},
+                    })
+                );
+            }
+        )
         .await;
 
     index
@@ -97,21 +71,17 @@ async fn formatted_contain_wildcard() {
             json!({ "q": "pésti", "attributesToRetrieve": ["*"], "attributesToCrop": ["*"] }),
             |response, code| {
                 assert_eq!(code, 200, "{}", response);
-                allow_duplicates! {
-                    assert_json_snapshot!(response["hits"][0],
-                    { "._rankingScore" => "[score]" },
-                    @r###"
-                    {
-                      "id": 852,
-                      "cattos": "pésti",
-                      "_formatted": {
-                        "id": "852",
-                        "cattos": "pésti"
-                      },
-                      "_rankingScore": "[score]"
-                    }
-                    "###);
-                }
+                assert_eq!(
+                    response["hits"][0],
+                    json!({
+                        "id": 852,
+                        "cattos": "pésti",
+                        "_formatted": {
+                            "id": "852",
+                            "cattos": "pésti",
+                        }
+                    })
+                );
             },
         )
         .await;
@@ -119,21 +89,17 @@ async fn formatted_contain_wildcard() {
     index
         .search(json!({ "q": "pésti", "attributesToCrop": ["*"] }), |response, code| {
             assert_eq!(code, 200, "{}", response);
-            allow_duplicates! {
-                assert_json_snapshot!(response["hits"][0],
-                { "._rankingScore" => "[score]" },
-                @r###"
-                {
-                  "id": 852,
-                  "cattos": "pésti",
-                  "_formatted": {
-                    "id": "852",
-                    "cattos": "pésti"
-                  },
-                  "_rankingScore": "[score]"
-                }
-                "###)
-            }
+            assert_eq!(
+                response["hits"][0],
+                json!({
+                    "id": 852,
+                    "cattos": "pésti",
+                    "_formatted": {
+                        "id": "852",
+                        "cattos": "pésti",
+                    }
+                })
+            );
         })
         .await;
 }
@@ -150,25 +116,21 @@ async fn format_nested() {
     index
         .search(json!({ "q": "pésti", "attributesToRetrieve": ["doggos"] }), |response, code| {
             assert_eq!(code, 200, "{}", response);
-            allow_duplicates! {
-                assert_json_snapshot!(response["hits"][0],
-                { "._rankingScore" => "[score]" },
-                @r###"
-                {
-                  "doggos": [
-                    {
-                      "name": "bobby",
-                      "age": 2
-                    },
-                    {
-                      "name": "buddy",
-                      "age": 4
-                    }
-                  ],
-                  "_rankingScore": "[score]"
-                }
-                "###)
-            }
+            assert_eq!(
+                response["hits"][0],
+                json!({
+                    "doggos": [
+                        {
+                            "name": "bobby",
+                            "age": 2,
+                        },
+                        {
+                            "name": "buddy",
+                            "age": 4,
+                        },
+                    ],
+                })
+            );
         })
         .await;
 
@@ -177,23 +139,19 @@ async fn format_nested() {
             json!({ "q": "pésti", "attributesToRetrieve": ["doggos.name"] }),
             |response, code| {
                 assert_eq!(code, 200, "{}", response);
-                allow_duplicates! {
-                    assert_json_snapshot!(response["hits"][0],
-                    { "._rankingScore" => "[score]" },
-                    @r###"
-                    {
-                      "doggos": [
-                        {
-                          "name": "bobby"
-                        },
-                        {
-                          "name": "buddy"
-                        }
-                      ],
-                      "_rankingScore": "[score]"
-                    }
-                    "###)
-                }
+                assert_eq!(
+                    response["hits"][0],
+                    json!({
+                        "doggos": [
+                            {
+                                "name": "bobby",
+                            },
+                            {
+                                "name": "buddy",
+                            },
+                        ],
+                    })
+                );
             },
         )
         .await;
@@ -203,31 +161,20 @@ async fn format_nested() {
             json!({ "q": "bobby", "attributesToRetrieve": ["doggos.name"], "showMatchesPosition": true }),
             |response, code| {
                 assert_eq!(code, 200, "{}", response);
-                allow_duplicates! {
-                    assert_json_snapshot!(response["hits"][0],
-                    { "._rankingScore" => "[score]" },
-                    @r###"
-                    {
-                      "doggos": [
-                        {
-                          "name": "bobby"
-                        },
-                        {
-                          "name": "buddy"
-                        }
-                      ],
-                      "_matchesPosition": {
-                        "doggos.name": [
-                          {
-                            "start": 0,
-                            "length": 5
-                          }
-                        ]
-                      },
-                      "_rankingScore": "[score]"
-                    }
-                    "###)
-                }
+                assert_eq!(
+                    response["hits"][0],
+                    json!({
+                        "doggos": [
+                            {
+                                "name": "bobby",
+                            },
+                            {
+                                "name": "buddy",
+                            },
+                        ],
+                        "_matchesPosition": {"doggos.name": [{"start": 0, "length": 5}]},
+                    })
+                );
             }
         )
         .await;
@@ -236,25 +183,21 @@ async fn format_nested() {
         .search(json!({ "q": "pésti", "attributesToRetrieve": [], "attributesToHighlight": ["doggos.name"] }),
         |response, code| {
             assert_eq!(code, 200, "{}", response);
-            allow_duplicates! {
-                assert_json_snapshot!(response["hits"][0],
-                { "._rankingScore" => "[score]" },
-                @r###"
-                {
-                  "_formatted": {
-                    "doggos": [
-                      {
-                        "name": "bobby"
-                      },
-                      {
-                        "name": "buddy"
-                      }
-                    ]
-                  },
-                  "_rankingScore": "[score]"
-                }
-                "###)
-            }
+            assert_eq!(
+                response["hits"][0],
+                json!({
+                    "_formatted": {
+                        "doggos": [
+                            {
+                                "name": "bobby",
+                            },
+                            {
+                                "name": "buddy",
+                            },
+                        ],
+                    },
+                })
+            );
         })
         .await;
 
@@ -262,25 +205,21 @@ async fn format_nested() {
         .search(json!({ "q": "pésti", "attributesToRetrieve": [], "attributesToCrop": ["doggos.name"] }),
         |response, code| {
             assert_eq!(code, 200, "{}", response);
-            allow_duplicates! {
-                assert_json_snapshot!(response["hits"][0],
-                { "._rankingScore" => "[score]" },
-                @r###"
-                {
-                  "_formatted": {
-                    "doggos": [
-                      {
-                        "name": "bobby"
-                      },
-                      {
-                        "name": "buddy"
-                      }
-                    ]
-                  },
-                  "_rankingScore": "[score]"
-                }
-                "###)
-            }
+            assert_eq!(
+                response["hits"][0],
+                json!({
+                    "_formatted": {
+                        "doggos": [
+                            {
+                                "name": "bobby",
+                            },
+                            {
+                                "name": "buddy",
+                            },
+                        ],
+                    },
+                })
+            );
         })
         .await;
 
@@ -288,63 +227,55 @@ async fn format_nested() {
         .search(json!({ "q": "pésti", "attributesToRetrieve": ["doggos.name"], "attributesToHighlight": ["doggos.age"] }),
         |response, code| {
     assert_eq!(code, 200, "{}", response);
-    allow_duplicates! {
-        assert_json_snapshot!(response["hits"][0],
-        { "._rankingScore" => "[score]" },
-        @r###"
-        {
-          "doggos": [
-            {
-              "name": "bobby"
-            },
-            {
-              "name": "buddy"
-            }
-          ],
-          "_formatted": {
+    assert_eq!(
+        response["hits"][0],
+        json!({
             "doggos": [
-              {
-                "name": "bobby",
-                "age": "2"
-              },
-              {
-                "name": "buddy",
-                "age": "4"
-              }
-            ]
-          },
-          "_rankingScore": "[score]"
-        }
-        "###)
-    }
-    })
+                {
+                    "name": "bobby",
+                },
+                {
+                    "name": "buddy",
+                },
+            ],
+            "_formatted": {
+                "doggos": [
+                    {
+                        "name": "bobby",
+                        "age": "2",
+                    },
+                    {
+                        "name": "buddy",
+                        "age": "4",
+                    },
+                ],
+            },
+        })
+    );
+        })
         .await;
 
     index
         .search(json!({ "q": "pésti", "attributesToRetrieve": [], "attributesToHighlight": ["doggos.age"], "attributesToCrop": ["doggos.name"] }),
         |response, code| {
                 assert_eq!(code, 200, "{}", response);
-                allow_duplicates! {
-                    assert_json_snapshot!(response["hits"][0],
-                    { "._rankingScore" => "[score]" },
-                    @r###"
+    assert_eq!(
+        response["hits"][0],
+        json!({
+            "_formatted": {
+                "doggos": [
                     {
-                      "_formatted": {
-                        "doggos": [
-                          {
-                            "name": "bobby",
-                            "age": "2"
-                          },
-                          {
-                            "name": "buddy",
-                            "age": "4"
-                          }
-                        ]
-                      },
-                      "_rankingScore": "[score]"
-                    }
-                    "###)
-                }
+                        "name": "bobby",
+                        "age": "2",
+                    },
+                    {
+                        "name": "buddy",
+                        "age": "4",
+                    },
+                ],
+            },
+        })
+    );
             }
         )
         .await;
@@ -366,70 +297,54 @@ async fn displayedattr_2_smol() {
         .search(json!({ "attributesToRetrieve": ["father", "id"], "attributesToHighlight": ["mother"], "attributesToCrop": ["cattos"] }),
         |response, code| {
     assert_eq!(code, 200, "{}", response);
-    allow_duplicates! {
-        assert_json_snapshot!(response["hits"][0],
-        { "._rankingScore" => "[score]" },
-        @r###"
-        {
-          "id": 852,
-          "_rankingScore": "[score]"
-        }
-        "###)
-    }
+    assert_eq!(
+        response["hits"][0],
+        json!({
+            "id": 852,
+        })
+    );
         })
         .await;
 
     index
         .search(json!({ "attributesToRetrieve": ["id"] }), |response, code| {
             assert_eq!(code, 200, "{}", response);
-            allow_duplicates! {
-                assert_json_snapshot!(response["hits"][0],
-                { "._rankingScore" => "[score]" },
-                @r###"
-                {
-                  "id": 852,
-                  "_rankingScore": "[score]"
-                }
-                "###)
-            }
+            assert_eq!(
+                response["hits"][0],
+                json!({
+                    "id": 852,
+                })
+            );
         })
         .await;
 
     index
         .search(json!({ "attributesToHighlight": ["id"] }), |response, code| {
             assert_eq!(code, 200, "{}", response);
-            allow_duplicates! {
-                assert_json_snapshot!(response["hits"][0],
-                { "._rankingScore" => "[score]" },
-                @r###"
-                {
-                  "id": 852,
-                  "_formatted": {
-                    "id": "852"
-                  },
-                  "_rankingScore": "[score]"
-                }
-                "###)
-            }
+            assert_eq!(
+                response["hits"][0],
+                json!({
+                    "id": 852,
+                    "_formatted": {
+                        "id": "852",
+                    }
+                })
+            );
         })
         .await;
 
     index
         .search(json!({ "attributesToCrop": ["id"] }), |response, code| {
             assert_eq!(code, 200, "{}", response);
-            allow_duplicates! {
-                assert_json_snapshot!(response["hits"][0],
-                { "._rankingScore" => "[score]" },
-                @r###"
-                {
-                  "id": 852,
-                  "_formatted": {
-                    "id": "852"
-                  },
-                  "_rankingScore": "[score]"
-                }
-                "###)
-            }
+            assert_eq!(
+                response["hits"][0],
+                json!({
+                    "id": 852,
+                    "_formatted": {
+                        "id": "852",
+                    }
+                })
+            );
         })
         .await;
 
@@ -438,19 +353,15 @@ async fn displayedattr_2_smol() {
             json!({ "attributesToHighlight": ["id"], "attributesToCrop": ["id"] }),
             |response, code| {
                 assert_eq!(code, 200, "{}", response);
-                allow_duplicates! {
-                    assert_json_snapshot!(response["hits"][0],
-                    { "._rankingScore" => "[score]" },
-                    @r###"
-                    {
-                      "id": 852,
-                      "_formatted": {
-                        "id": "852"
-                      },
-                      "_rankingScore": "[score]"
-                    }
-                    "###)
-                }
+                assert_eq!(
+                    response["hits"][0],
+                    json!({
+                        "id": 852,
+                        "_formatted": {
+                            "id": "852",
+                        }
+                    })
+                );
             },
         )
         .await;
@@ -458,47 +369,31 @@ async fn displayedattr_2_smol() {
     index
         .search(json!({ "attributesToHighlight": ["cattos"] }), |response, code| {
             assert_eq!(code, 200, "{}", response);
-            allow_duplicates! {
-                assert_json_snapshot!(response["hits"][0],
-                { "._rankingScore" => "[score]" },
-                @r###"
-                {
-                  "id": 852,
-                  "_rankingScore": "[score]"
-                }
-                "###)
-            }
+            assert_eq!(
+                response["hits"][0],
+                json!({
+                    "id": 852,
+                })
+            );
         })
         .await;
 
     index
         .search(json!({ "attributesToCrop": ["cattos"] }), |response, code| {
             assert_eq!(code, 200, "{}", response);
-            allow_duplicates! {
-                assert_json_snapshot!(response["hits"][0],
-                { "._rankingScore" => "[score]" },
-                @r###"
-                {
-                  "id": 852,
-                  "_rankingScore": "[score]"
-                }
-                "###)
-            }
+            assert_eq!(
+                response["hits"][0],
+                json!({
+                    "id": 852,
+                })
+            );
         })
         .await;
 
     index
         .search(json!({ "attributesToRetrieve": ["cattos"] }), |response, code| {
             assert_eq!(code, 200, "{}", response);
-            allow_duplicates! {
-                assert_json_snapshot!(response["hits"][0],
-                { "._rankingScore" => "[score]" },
-                @r###"
-                {
-                  "_rankingScore": "[score]"
-                }
-                "###)
-            }
+            assert_eq!(response["hits"][0], json!({}));
         })
         .await;
 
@@ -507,15 +402,7 @@ async fn displayedattr_2_smol() {
             json!({ "attributesToRetrieve": ["cattos"], "attributesToHighlight": ["cattos"], "attributesToCrop": ["cattos"] }),
             |response, code| {
     assert_eq!(code, 200, "{}", response);
-    allow_duplicates! {
-        assert_json_snapshot!(response["hits"][0],
-        { "._rankingScore" => "[score]" },
-        @r###"
-        {
-          "_rankingScore": "[score]"
-        }
-        "###)
-    }
+    assert_eq!(response["hits"][0], json!({}));
 
             }
         )
@@ -526,18 +413,14 @@ async fn displayedattr_2_smol() {
             json!({ "attributesToRetrieve": ["cattos"], "attributesToHighlight": ["id"] }),
             |response, code| {
                 assert_eq!(code, 200, "{}", response);
-                allow_duplicates! {
-                    assert_json_snapshot!(response["hits"][0],
-                    { "._rankingScore" => "[score]" },
-                    @r###"
-                    {
-                      "_formatted": {
-                        "id": "852"
-                      },
-                      "_rankingScore": "[score]"
-                    }
-                    "###)
-                }
+                assert_eq!(
+                    response["hits"][0],
+                    json!({
+                        "_formatted": {
+                            "id": "852",
+                        }
+                    })
+                );
             },
         )
         .await;
@@ -547,18 +430,14 @@ async fn displayedattr_2_smol() {
             json!({ "attributesToRetrieve": ["cattos"], "attributesToCrop": ["id"] }),
             |response, code| {
                 assert_eq!(code, 200, "{}", response);
-                allow_duplicates! {
-                    assert_json_snapshot!(response["hits"][0],
-                    { "._rankingScore" => "[score]" },
-                    @r###"
-                    {
-                      "_formatted": {
-                        "id": "852"
-                      },
-                      "_rankingScore": "[score]"
-                    }
-                    "###)
-                }
+                assert_eq!(
+                    response["hits"][0],
+                    json!({
+                        "_formatted": {
+                            "id": "852",
+                        }
+                    })
+                );
             },
         )
         .await;

meilisearch/tests/search/multi.rs

@@ -65,15 +65,14 @@ async fn simple_search_single_index() {
         ]}))
         .await;
     snapshot!(code, @"200 OK");
-    insta::assert_json_snapshot!(response["results"], { "[].processingTimeMs" => "[time]", ".**._rankingScore" => "[score]" }, @r###"
+    insta::assert_json_snapshot!(response["results"], { "[].processingTimeMs" => "[time]" }, @r###"
     [
       {
         "indexUid": "test",
         "hits": [
           {
             "title": "Gläss",
-            "id": "450465",
-            "_rankingScore": "[score]"
+            "id": "450465"
           }
         ],
         "query": "glass",
@@ -87,8 +86,7 @@ async fn simple_search_single_index() {
         "hits": [
           {
             "title": "Captain Marvel",
-            "id": "299537",
-            "_rankingScore": "[score]"
+            "id": "299537"
           }
         ],
         "query": "captain",
@@ -172,15 +170,14 @@ async fn simple_search_two_indexes() {
         ]}))
         .await;
     snapshot!(code, @"200 OK");
-    insta::assert_json_snapshot!(response["results"], { "[].processingTimeMs" => "[time]", ".**._rankingScore" => "[score]" }, @r###"
+    insta::assert_json_snapshot!(response["results"], { "[].processingTimeMs" => "[time]" }, @r###"
     [
       {
         "indexUid": "test",
         "hits": [
           {
             "title": "Gläss",
-            "id": "450465",
-            "_rankingScore": "[score]"
+            "id": "450465"
           }
         ],
         "query": "glass",
@@ -206,8 +203,7 @@ async fn simple_search_two_indexes() {
                 "age": 4
               }
             ],
-            "cattos": "pésti",
-            "_rankingScore": "[score]"
+            "cattos": "pésti"
           },
           {
             "id": 654,
@@ -222,8 +218,7 @@ async fn simple_search_two_indexes() {
             "cattos": [
               "simba",
               "pestiféré"
-            ],
-            "_rankingScore": "[score]"
+            ]
           }
         ],
         "query": "pésti",

milli/Cargo.toml

@@ -15,6 +15,7 @@ license.workspace = true
 bimap = { version = "0.6.3", features = ["serde"] }
 bincode = "1.3.3"
 bstr = "1.4.0"
+bytemuck = { version = "1.13.1", features = ["extern_crate_alloc"] }
 byteorder = "1.4.3"
 charabia = { version = "0.7.2", default-features = false }
 concat-arrays = "0.1.2"
@@ -32,18 +33,21 @@ heed = { git = "https://github.com/meilisearch/heed", tag = "v0.12.6", default-f
     "lmdb",
     "sync-read-txn",
 ] }
+hnsw = { version = "0.11.0", features = ["serde1"] }
 json-depth-checker = { path = "../json-depth-checker" }
 levenshtein_automata = { version = "0.2.1", features = ["fst_automaton"] }
 memmap2 = "0.5.10"
 obkv = "0.2.0"
 once_cell = "1.17.1"
 ordered-float = "3.6.0"
+rand_pcg = { version = "0.3.1", features = ["serde1"] }
 rayon = "1.7.0"
 roaring = "0.10.1"
 rstar = { version = "0.10.0", features = ["serde"] }
 serde = { version = "1.0.160", features = ["derive"] }
 serde_json = { version = "1.0.95", features = ["preserve_order"] }
 slice-group-by = "0.3.0"
+space = "0.17.0"
 smallstr = { version = "0.3.0", features = ["serde"] }
 smallvec = "1.10.0"
 smartstring = "1.0.1"

milli/examples/search.rs

@@ -52,6 +52,7 @@ fn main() -> Result<(), Box<dyn Error>> {
             let docs = execute_search(
                 &mut ctx,
                 &(!query.trim().is_empty()).then(|| query.trim().to_owned()),
+                &None,
                 TermsMatchingStrategy::Last,
                 false,
                 &None,

milli/src/distance.rs

@@ -0,0 +1,34 @@
+use serde::{Deserialize, Serialize};
+use space::Metric;
+
+#[derive(Debug, Default, Clone, Copy, Serialize, Deserialize)]
+pub struct DotProduct;
+
+impl Metric<Vec<f32>> for DotProduct {
+    type Unit = u32;
+
+    // TODO explain me this function, I don't understand why f32.to_bits is ordered.
+    // I tried to do this and it wasn't OK <https://stackoverflow.com/a/43305015/1941280>
+    //
+    // Following <https://docs.rs/space/0.17.0/space/trait.Metric.html>.
+    fn distance(&self, a: &Vec<f32>, b: &Vec<f32>) -> Self::Unit {
+        let dist: f32 = a.iter().zip(b).map(|(a, b)| a * b).sum();
+        let dist = 1.0 - dist;
+        debug_assert!(!dist.is_nan());
+        dist.to_bits()
+    }
+}
+
+#[derive(Debug, Default, Clone, Copy, Serialize, Deserialize)]
+pub struct Euclidean;
+
+impl Metric<Vec<f32>> for Euclidean {
+    type Unit = u32;
+
+    fn distance(&self, a: &Vec<f32>, b: &Vec<f32>) -> Self::Unit {
+        let squared: f32 = a.iter().zip(b).map(|(a, b)| (a - b).powi(2)).sum();
+        let dist = squared.sqrt();
+        debug_assert!(!dist.is_nan());
+        dist.to_bits()
+    }
+}

milli/src/error.rs

@@ -110,9 +110,11 @@ only composed of alphanumeric characters (a-z A-Z 0-9), hyphens (-) and undersco
     },
     #[error(transparent)]
     InvalidGeoField(#[from] GeoError),
+    #[error("Invalid vector dimensions: expected: `{}`, found: `{}`.", .expected, .found)]
+    InvalidVectorDimensions { expected: usize, found: usize },
     #[error("{0}")]
     InvalidFilter(String),
-    #[error("Invalid type for filter subexpression: `expected {}, found: {1}`.", .0.join(", "))]
+    #[error("Invalid type for filter subexpression: expected: {}, found: {1}.", .0.join(", "))]
     InvalidFilterExpression(&'static [&'static str], Value),
     #[error("Attribute `{}` is not sortable. {}",
         .field,

milli/src/index.rs

@@ -8,10 +8,12 @@ use charabia::{Language, Script};
 use heed::flags::Flags;
 use heed::types::*;
 use heed::{CompactionOption, Database, PolyDatabase, RoTxn, RwTxn};
+use rand_pcg::Pcg32;
 use roaring::RoaringBitmap;
 use rstar::RTree;
 use time::OffsetDateTime;
 
+use crate::distance::DotProduct;
 use crate::error::{InternalError, UserError};
 use crate::facet::FacetType;
 use crate::fields_ids_map::FieldsIdsMap;
@@ -26,6 +28,9 @@ use crate::{
     Result, RoaringBitmapCodec, RoaringBitmapLenCodec, Search, U8StrStrCodec, BEU16, BEU32,
 };
 
+/// The HNSW data-structure that we serialize, fill and search in.
+pub type Hnsw = hnsw::Hnsw<DotProduct, Vec<f32>, Pcg32, 12, 24>;
+
 pub const DEFAULT_MIN_WORD_LEN_ONE_TYPO: u8 = 5;
 pub const DEFAULT_MIN_WORD_LEN_TWO_TYPOS: u8 = 9;
 
@@ -42,6 +47,7 @@ pub mod main_key {
     pub const FIELDS_IDS_MAP_KEY: &str = "fields-ids-map";
     pub const GEO_FACETED_DOCUMENTS_IDS_KEY: &str = "geo-faceted-documents-ids";
     pub const GEO_RTREE_KEY: &str = "geo-rtree";
+    pub const VECTOR_HNSW_KEY: &str = "vector-hnsw";
     pub const HARD_EXTERNAL_DOCUMENTS_IDS_KEY: &str = "hard-external-documents-ids";
     pub const NUMBER_FACETED_DOCUMENTS_IDS_PREFIX: &str = "number-faceted-documents-ids";
     pub const PRIMARY_KEY_KEY: &str = "primary-key";
@@ -86,6 +92,7 @@ pub mod db_name {
     pub const FACET_ID_STRING_DOCIDS: &str = "facet-id-string-docids";
     pub const FIELD_ID_DOCID_FACET_F64S: &str = "field-id-docid-facet-f64s";
     pub const FIELD_ID_DOCID_FACET_STRINGS: &str = "field-id-docid-facet-strings";
+    pub const VECTOR_ID_DOCID: &str = "vector-id-docids";
     pub const DOCUMENTS: &str = "documents";
     pub const SCRIPT_LANGUAGE_DOCIDS: &str = "script_language_docids";
 }
@@ -149,6 +156,9 @@ pub struct Index {
     /// Maps the document id, the facet field id and the strings.
     pub field_id_docid_facet_strings: Database<FieldDocIdFacetStringCodec, Str>,
 
+    /// Maps a vector id to the document id that have it.
+    pub vector_id_docid: Database<OwnedType<BEU32>, OwnedType<BEU32>>,
+
     /// Maps the document id to the document as an obkv store.
     pub(crate) documents: Database<OwnedType<BEU32>, ObkvCodec>,
 }
@@ -162,7 +172,7 @@ impl Index {
     ) -> Result<Index> {
         use db_name::*;
 
-        options.max_dbs(23);
+        options.max_dbs(24);
         unsafe { options.flag(Flags::MdbAlwaysFreePages) };
 
         let env = options.open(path)?;
@@ -198,11 +208,11 @@ impl Index {
             env.create_database(&mut wtxn, Some(FACET_ID_IS_NULL_DOCIDS))?;
         let facet_id_is_empty_docids =
             env.create_database(&mut wtxn, Some(FACET_ID_IS_EMPTY_DOCIDS))?;
-
         let field_id_docid_facet_f64s =
             env.create_database(&mut wtxn, Some(FIELD_ID_DOCID_FACET_F64S))?;
         let field_id_docid_facet_strings =
             env.create_database(&mut wtxn, Some(FIELD_ID_DOCID_FACET_STRINGS))?;
+        let vector_id_docid = env.create_database(&mut wtxn, Some(VECTOR_ID_DOCID))?;
         let documents = env.create_database(&mut wtxn, Some(DOCUMENTS))?;
         wtxn.commit()?;
 
@@ -231,6 +241,7 @@ impl Index {
             facet_id_is_empty_docids,
             field_id_docid_facet_f64s,
             field_id_docid_facet_strings,
+            vector_id_docid,
             documents,
         })
     }
@@ -502,6 +513,26 @@ impl Index {
         }
     }
 
+    /* vector HNSW */
+
+    /// Writes the provided `hnsw`.
+    pub(crate) fn put_vector_hnsw(&self, wtxn: &mut RwTxn, hnsw: &Hnsw) -> heed::Result<()> {
+        self.main.put::<_, Str, SerdeBincode<Hnsw>>(wtxn, main_key::VECTOR_HNSW_KEY, hnsw)
+    }
+
+    /// Delete the `hnsw`.
+    pub(crate) fn delete_vector_hnsw(&self, wtxn: &mut RwTxn) -> heed::Result<bool> {
+        self.main.delete::<_, Str>(wtxn, main_key::VECTOR_HNSW_KEY)
+    }
+
+    /// Returns the `hnsw`.
+    pub fn vector_hnsw(&self, rtxn: &RoTxn) -> Result<Option<Hnsw>> {
+        match self.main.get::<_, Str, SerdeBincode<Hnsw>>(rtxn, main_key::VECTOR_HNSW_KEY)? {
+            Some(hnsw) => Ok(Some(hnsw)),
+            None => Ok(None),
+        }
+    }
+
     /* field distribution */
 
     /// Writes the field distribution which associates every field name with
@@ -1466,9 +1497,9 @@ pub(crate) mod tests {
 
         db_snap!(index, field_distribution,
             @r###"
-        age              1     
-        id               2     
-        name             2     
+        age              1      |
+        id               2      |
+        name             2      |
         "###
         );
 
@@ -1486,9 +1517,9 @@ pub(crate) mod tests {
 
         db_snap!(index, field_distribution,
             @r###"
-        age              1     
-        id               2     
-        name             2     
+        age              1      |
+        id               2      |
+        name             2      |
         "###
         );
 
@@ -1502,9 +1533,9 @@ pub(crate) mod tests {
 
         db_snap!(index, field_distribution,
             @r###"
-        has_dog          1     
-        id               2     
-        name             2     
+        has_dog          1      |
+        id               2      |
+        name             2      |
         "###
         );
     }
@@ -2488,12 +2519,8 @@ pub(crate) mod tests {
 
         let rtxn = index.read_txn().unwrap();
         let search = Search::new(&rtxn, &index);
-        let SearchResult {
-            matching_words: _,
-            candidates: _,
-            document_scores: _,
-            mut documents_ids,
-        } = search.execute().unwrap();
+        let SearchResult { matching_words: _, candidates: _, mut documents_ids } =
+            search.execute().unwrap();
         let primary_key_id = index.fields_ids_map(&rtxn).unwrap().id("primary_key").unwrap();
         documents_ids.sort_unstable();
         let docs = index.documents(&rtxn, documents_ids).unwrap();

milli/src/lib.rs

@@ -10,6 +10,7 @@ pub mod documents;
 
 mod asc_desc;
 mod criterion;
+pub mod distance;
 mod error;
 mod external_documents_ids;
 pub mod facet;
@@ -17,7 +18,6 @@ mod fields_ids_map;
 pub mod heed_codec;
 pub mod index;
 pub mod proximity;
-pub mod score_details;
 mod search;
 pub mod update;
 

milli/src/score_details.rs

@@ -1,544 +0,0 @@
-use std::cmp::Ordering;
-
-use serde::Serialize;
-
-use crate::distance_between_two_points;
-
-#[derive(Debug, Clone, PartialEq)]
-pub enum ScoreDetails {
-    Words(Words),
-    Typo(Typo),
-    Proximity(Rank),
-    Fid(Rank),
-    Position(Rank),
-    ExactAttribute(ExactAttribute),
-    Exactness(Rank),
-    Sort(Sort),
-    GeoSort(GeoSort),
-}
-
-impl PartialOrd for ScoreDetails {
-    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
-        use ScoreDetails::*;
-        match (self, other) {
-            // matching left and right hands => defer to sub impl
-            (Words(left), Words(right)) => left.partial_cmp(right),
-            (Typo(left), Typo(right)) => left.partial_cmp(right),
-            (Proximity(left), Proximity(right)) => left.partial_cmp(right),
-            (Fid(left), Fid(right)) => left.partial_cmp(right),
-            (Position(left), Position(right)) => left.partial_cmp(right),
-            (ExactAttribute(left), ExactAttribute(right)) => left.partial_cmp(right),
-            (Exactness(left), Exactness(right)) => left.partial_cmp(right),
-            (Sort(left), Sort(right)) => left.partial_cmp(right),
-            (GeoSort(left), GeoSort(right)) => left.partial_cmp(right),
-            // non matching left and right hands => None
-            // written this way rather than with a single `_` arm, so that adding a new variant
-            // still results in a compile error
-            (Words(_), _) => None,
-            (Typo(_), _) => None,
-            (Proximity(_), _) => None,
-            (Fid(_), _) => None,
-            (Position(_), _) => None,
-            (ExactAttribute(_), _) => None,
-            (Exactness(_), _) => None,
-            (Sort(_), _) => None,
-            (GeoSort(_), _) => None,
-        }
-    }
-}
-
-impl ScoreDetails {
-    pub fn local_score(&self) -> Option<f64> {
-        self.rank().map(Rank::local_score)
-    }
-
-    pub fn rank(&self) -> Option<Rank> {
-        match self {
-            ScoreDetails::Words(details) => Some(details.rank()),
-            ScoreDetails::Typo(details) => Some(details.rank()),
-            ScoreDetails::Proximity(details) => Some(*details),
-            ScoreDetails::Fid(details) => Some(*details),
-            ScoreDetails::Position(details) => Some(*details),
-            ScoreDetails::ExactAttribute(details) => Some(details.rank()),
-            ScoreDetails::Exactness(details) => Some(*details),
-            ScoreDetails::Sort(_) => None,
-            ScoreDetails::GeoSort(_) => None,
-        }
-    }
-
-    pub fn global_score<'a>(details: impl Iterator<Item = &'a Self>) -> f64 {
-        Rank::global_score(details.filter_map(Self::rank))
-    }
-
-    pub fn global_score_linear_scale<'a>(details: impl Iterator<Item = &'a Self>) -> u64 {
-        (Self::global_score(details) * LINEAR_SCALE_FACTOR).round() as u64
-    }
-
-    /// Panics
-    ///
-    /// - If Position is not preceded by Fid
-    /// - If Exactness is not preceded by ExactAttribute
-    /// - If a sort fid is not contained in the passed `fields_ids_map`.
-    pub fn to_json_map<'a>(
-        details: impl Iterator<Item = &'a Self>,
-    ) -> serde_json::Map<String, serde_json::Value> {
-        let mut order = 0;
-        let mut details_map = serde_json::Map::default();
-        for details in details {
-            match details {
-                ScoreDetails::Words(words) => {
-                    let words_details = serde_json::json!({
-                            "order": order,
-                            "matchingWords": words.matching_words,
-                            "maxMatchingWords": words.max_matching_words,
-                            "score": words.rank().local_score_linear_scale(),
-                    });
-                    details_map.insert("words".into(), words_details);
-                    order += 1;
-                }
-                ScoreDetails::Typo(typo) => {
-                    let typo_details = serde_json::json!({
-                        "order": order,
-                        "typoCount": typo.typo_count,
-                        "maxTypoCount": typo.max_typo_count,
-                        "score": typo.rank().local_score_linear_scale(),
-                    });
-                    details_map.insert("typo".into(), typo_details);
-                    order += 1;
-                }
-                ScoreDetails::Proximity(proximity) => {
-                    let proximity_details = serde_json::json!({
-                        "order": order,
-                        "score": proximity.local_score_linear_scale(),
-                    });
-                    details_map.insert("proximity".into(), proximity_details);
-                    order += 1;
-                }
-                ScoreDetails::Fid(fid) => {
-                    // For now, fid is a virtual rule always followed by the "position" rule
-                    let fid_details = serde_json::json!({
-                        "order": order,
-                        "attributes_ranking_order": fid.local_score_linear_scale(),
-                    });
-                    details_map.insert("attribute".into(), fid_details);
-                    order += 1;
-                }
-                ScoreDetails::Position(position) => {
-                    // For now, position is a virtual rule always preceded by the "fid" rule
-                    let attribute_details = details_map
-                        .get_mut("attribute")
-                        .expect("position not preceded by attribute");
-                    let attribute_details = attribute_details
-                        .as_object_mut()
-                        .expect("attribute details was not an object");
-                    attribute_details.insert(
-                        "attributes_query_word_order".into(),
-                        position.local_score_linear_scale().into(),
-                    );
-                    // do not update the order since this was already done by fid
-                }
-                ScoreDetails::ExactAttribute(exact_attribute) => {
-                    let exactness_details = serde_json::json!({
-                        "order": order,
-                        "exactIn": exact_attribute,
-                        "score": exact_attribute.rank().local_score_linear_scale(),
-                    });
-                    details_map.insert("exactness".into(), exactness_details);
-                    order += 1;
-                }
-                ScoreDetails::Exactness(details) => {
-                    // For now, exactness is a virtual rule always preceded by the "ExactAttribute" rule
-                    let exactness_details = details_map
-                        .get_mut("exactness")
-                        .expect("Exactness not preceded by exactAttribute");
-                    let exactness_details = exactness_details
-                        .as_object_mut()
-                        .expect("exactness details was not an object");
-                    if exactness_details.get("exactIn").expect("missing 'exactIn'")
-                        == &serde_json::json!(ExactAttribute::NoExactMatch)
-                    {
-                        let score = Rank::global_score_linear_scale(
-                            [ExactAttribute::NoExactMatch.rank(), *details].iter().copied(),
-                        );
-                        *exactness_details.get_mut("score").expect("missing score") = score.into();
-                    }
-                    // do not update the order since this was already done by exactAttribute
-                }
-                ScoreDetails::Sort(details) => {
-                    let sort = format!(
-                        "{}:{}",
-                        details.field_name,
-                        if details.ascending { "asc" } else { "desc" }
-                    );
-                    let sort_details = serde_json::json!({
-                        "order": order,
-                        "value": details.value,
-                    });
-                    details_map.insert(sort, sort_details);
-                    order += 1;
-                }
-                ScoreDetails::GeoSort(details) => {
-                    let sort = format!(
-                        "_geoPoint({}, {}):{}",
-                        details.target_point[0],
-                        details.target_point[1],
-                        if details.ascending { "asc" } else { "desc" }
-                    );
-                    let point = if let Some(value) = details.value {
-                        serde_json::json!({ "lat": value[0], "lng": value[1]})
-                    } else {
-                        serde_json::Value::Null
-                    };
-                    let sort_details = serde_json::json!({
-                        "order": order,
-                        "value": point,
-                        "distance": details.distance(),
-                    });
-                    details_map.insert(sort, sort_details);
-                    order += 1;
-                }
-            }
-        }
-        details_map
-    }
-
-    pub fn partial_cmp_iter<'a>(
-        mut left: impl Iterator<Item = &'a Self>,
-        mut right: impl Iterator<Item = &'a Self>,
-    ) -> Result<Ordering, NotComparable> {
-        let mut index = 0;
-        let mut order = match (left.next(), right.next()) {
-            (Some(left), Some(right)) => left.partial_cmp(right).incomparable(index)?,
-            _ => return Ok(Ordering::Equal),
-        };
-        for (left, right) in left.zip(right) {
-            if order != Ordering::Equal {
-                return Ok(order);
-            };
-
-            index += 1;
-            order = left.partial_cmp(right).incomparable(index)?;
-        }
-        Ok(order)
-    }
-}
-
-#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
-pub struct NotComparable(pub usize);
-
-trait OptionToNotComparable<T> {
-    fn incomparable(self, index: usize) -> Result<T, NotComparable>;
-}
-
-impl<T> OptionToNotComparable<T> for Option<T> {
-    fn incomparable(self, index: usize) -> Result<T, NotComparable> {
-        match self {
-            Some(t) => Ok(t),
-            None => Err(NotComparable(index)),
-        }
-    }
-}
-
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
-pub struct Words {
-    pub matching_words: u32,
-    pub max_matching_words: u32,
-}
-
-impl PartialOrd for Words {
-    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
-        (self.max_matching_words == other.max_matching_words)
-            .then(|| self.matching_words.cmp(&other.matching_words))
-    }
-}
-
-impl Words {
-    pub fn rank(&self) -> Rank {
-        Rank { rank: self.matching_words, max_rank: self.max_matching_words }
-    }
-
-    pub(crate) fn from_rank(rank: Rank) -> Words {
-        Words { matching_words: rank.rank, max_matching_words: rank.max_rank }
-    }
-}
-
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
-pub struct Typo {
-    pub typo_count: u32,
-    pub max_typo_count: u32,
-}
-
-impl PartialOrd for Typo {
-    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
-        (self.max_typo_count == other.max_typo_count).then(|| {
-            // the order is reverted as having fewer typos gives a better score
-            self.typo_count.cmp(&other.typo_count).reverse()
-        })
-    }
-}
-
-impl Typo {
-    pub fn rank(&self) -> Rank {
-        Rank {
-            rank: self.max_typo_count - self.typo_count + 1,
-            max_rank: (self.max_typo_count + 1),
-        }
-    }
-
-    // max_rank = max_typo + 1
-    // max_typo = max_rank - 1
-    //
-    // rank = max_typo - typo + 1
-    // rank = max_rank - 1 - typo + 1
-    // rank + typo = max_rank
-    // typo = max_rank - rank
-    pub fn from_rank(rank: Rank) -> Typo {
-        Typo { typo_count: rank.max_rank - rank.rank, max_typo_count: rank.max_rank - 1 }
-    }
-}
-
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
-pub struct Rank {
-    /// The ordinal rank, such that `max_rank` is the first rank, and 0 is the last rank.
-    ///
-    /// The higher the better. Documents with a rank of 0 have a score of 0 and are typically never returned
-    /// (they don't match the query).
-    pub rank: u32,
-    /// The maximum possible rank. Documents with this rank have a score of 1.
-    ///
-    /// The max rank should not be 0.
-    pub max_rank: u32,
-}
-
-impl PartialOrd for Rank {
-    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
-        (self.max_rank == other.max_rank).then(|| self.rank.cmp(&other.rank))
-    }
-}
-
-impl Rank {
-    pub fn local_score(self) -> f64 {
-        self.rank as f64 / self.max_rank as f64
-    }
-
-    pub fn local_score_linear_scale(self) -> u64 {
-        (self.local_score() * LINEAR_SCALE_FACTOR).round() as u64
-    }
-
-    pub fn global_score(details: impl Iterator<Item = Self>) -> f64 {
-        let mut rank = Rank { rank: 1, max_rank: 1 };
-        for inner_rank in details {
-            rank.rank -= 1;
-
-            rank.rank *= inner_rank.max_rank;
-            rank.max_rank *= inner_rank.max_rank;
-
-            rank.rank += inner_rank.rank;
-        }
-        rank.local_score()
-    }
-
-    pub fn global_score_linear_scale(details: impl Iterator<Item = Self>) -> u64 {
-        (Self::global_score(details) * LINEAR_SCALE_FACTOR).round() as u64
-    }
-}
-
-#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash, Serialize)]
-#[serde(rename_all = "camelCase")]
-pub enum ExactAttribute {
-    // Do not reorder as the order is significant, from least relevant to most relevant
-    NoExactMatch,
-    MatchesStart,
-    MatchesFull,
-}
-
-impl ExactAttribute {
-    pub fn rank(&self) -> Rank {
-        let rank = match self {
-            ExactAttribute::MatchesFull => 3,
-            ExactAttribute::MatchesStart => 2,
-            ExactAttribute::NoExactMatch => 1,
-        };
-        Rank { rank, max_rank: 3 }
-    }
-}
-
-#[derive(Debug, Clone, PartialEq)]
-pub struct Sort {
-    pub field_name: String,
-    pub ascending: bool,
-    pub value: serde_json::Value,
-}
-
-impl PartialOrd for Sort {
-    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
-        if self.field_name != other.field_name {
-            return None;
-        }
-        if self.ascending != other.ascending {
-            return None;
-        }
-        match (&self.value, &other.value) {
-            (serde_json::Value::Null, serde_json::Value::Null) => Some(Ordering::Equal),
-            (serde_json::Value::Null, _) => Some(Ordering::Less),
-            (_, serde_json::Value::Null) => Some(Ordering::Greater),
-            // numbers are always before strings
-            (serde_json::Value::Number(_), serde_json::Value::String(_)) => Some(Ordering::Greater),
-            (serde_json::Value::String(_), serde_json::Value::Number(_)) => Some(Ordering::Less),
-            (serde_json::Value::Number(left), serde_json::Value::Number(right)) => {
-                //FIXME: unwrap permitted here?
-                let order = left.as_f64().unwrap().partial_cmp(&right.as_f64().unwrap())?;
-                // always reverted, as bigger is better
-                Some(if self.ascending { order.reverse() } else { order })
-            }
-            (serde_json::Value::String(left), serde_json::Value::String(right)) => {
-                let order = left.cmp(right);
-                Some(if self.ascending { order.reverse() } else { order })
-            }
-            _ => None,
-        }
-    }
-}
-
-#[derive(Debug, Clone, Copy, PartialEq)]
-pub struct GeoSort {
-    pub target_point: [f64; 2],
-    pub ascending: bool,
-    pub value: Option<[f64; 2]>,
-}
-
-impl PartialOrd for GeoSort {
-    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
-        if self.target_point != other.target_point {
-            return None;
-        }
-        if self.ascending != other.ascending {
-            return None;
-        }
-        Some(match (self.distance(), other.distance()) {
-            (None, None) => Ordering::Equal,
-            (None, Some(_)) => Ordering::Less,
-            (Some(_), None) => Ordering::Greater,
-            (Some(left), Some(right)) => {
-                let order = left.partial_cmp(&right)?;
-                if self.ascending {
-                    // when ascending, the one with the smallest distance has the best score
-                    order.reverse()
-                } else {
-                    order
-                }
-            }
-        })
-    }
-}
-
-impl GeoSort {
-    pub fn distance(&self) -> Option<f64> {
-        self.value.map(|value| distance_between_two_points(&self.target_point, &value))
-    }
-}
-
-const LINEAR_SCALE_FACTOR: f64 = 1000.0;
-
-#[cfg(test)]
-mod test {
-    use super::*;
-    #[test]
-    fn compare() {
-        let left = [
-            ScoreDetails::Words(Words { matching_words: 3, max_matching_words: 4 }),
-            ScoreDetails::Sort(Sort {
-                field_name: "doggo".into(),
-                ascending: true,
-                value: "Intel the Beagle".into(),
-            }),
-        ];
-        let right = [
-            ScoreDetails::Words(Words { matching_words: 3, max_matching_words: 4 }),
-            ScoreDetails::Sort(Sort {
-                field_name: "doggo".into(),
-                ascending: true,
-                value: "Max the Labrador".into(),
-            }),
-        ];
-        assert_eq!(
-            Ok(Ordering::Greater),
-            ScoreDetails::partial_cmp_iter(left.iter(), right.iter())
-        );
-        // equal when all the common components are equal
-        assert_eq!(
-            Ok(Ordering::Equal),
-            ScoreDetails::partial_cmp_iter(left[0..1].iter(), right.iter())
-        );
-
-        let right = [
-            ScoreDetails::Words(Words { matching_words: 4, max_matching_words: 4 }),
-            ScoreDetails::Sort(Sort {
-                field_name: "doggo".into(),
-                ascending: true,
-                value: "Max the Labrador".into(),
-            }),
-        ];
-
-        assert_eq!(Ok(Ordering::Less), ScoreDetails::partial_cmp_iter(left.iter(), right.iter()));
-    }
-
-    #[test]
-    fn sort_not_comparable() {
-        let left = [
-            ScoreDetails::Words(Words { matching_words: 3, max_matching_words: 4 }),
-            ScoreDetails::Sort(Sort {
-                // not the same field name
-                field_name: "catto".into(),
-                ascending: true,
-                value: "Sylver the cat".into(),
-            }),
-        ];
-        let right = [
-            ScoreDetails::Words(Words { matching_words: 3, max_matching_words: 4 }),
-            ScoreDetails::Sort(Sort {
-                field_name: "doggo".into(),
-                ascending: true,
-                value: "Max the Labrador".into(),
-            }),
-        ];
-        assert_eq!(
-            Err(NotComparable(1)),
-            ScoreDetails::partial_cmp_iter(left.iter(), right.iter())
-        );
-        let left = [
-            ScoreDetails::Words(Words { matching_words: 3, max_matching_words: 4 }),
-            ScoreDetails::Sort(Sort {
-                field_name: "doggo".into(),
-                // Not the same order
-                ascending: false,
-                value: "Intel the Beagle".into(),
-            }),
-        ];
-        let right = [
-            ScoreDetails::Words(Words { matching_words: 3, max_matching_words: 4 }),
-            ScoreDetails::Sort(Sort {
-                field_name: "doggo".into(),
-                ascending: true,
-                value: "Max the Labrador".into(),
-            }),
-        ];
-        assert_eq!(
-            Err(NotComparable(1)),
-            ScoreDetails::partial_cmp_iter(left.iter(), right.iter())
-        );
-    }
-
-    #[test]
-    fn sort_behavior() {
-        let left = Sort { field_name: "price".into(), ascending: true, value: "5400".into() };
-        let right = Sort { field_name: "price".into(), ascending: true, value: 53.into() };
-        // number always better match than strings
-        assert_eq!(Some(Ordering::Less), left.partial_cmp(&right));
-
-        let left = Sort { field_name: "price".into(), ascending: false, value: "5400".into() };
-        let right = Sort { field_name: "price".into(), ascending: false, value: 53.into() };
-        // true regardless of the sort direction
-        assert_eq!(Some(Ordering::Less), left.partial_cmp(&right));
-    }
-}

milli/src/search/mod.rs

@@ -7,7 +7,6 @@ use roaring::bitmap::RoaringBitmap;
 pub use self::facet::{FacetDistribution, Filter, DEFAULT_VALUES_PER_FACET};
 pub use self::new::matches::{FormatOptions, MatchBounds, Matcher, MatcherBuilder, MatchingWords};
 use self::new::PartialSearchResult;
-use crate::score_details::ScoreDetails;
 use crate::{
     execute_search, AscDesc, DefaultSearchLogger, DocumentId, Index, Result, SearchContext,
 };
@@ -23,6 +22,7 @@ pub mod new;
 
 pub struct Search<'a> {
     query: Option<String>,
+    vector: Option<Vec<f32>>,
     // this should be linked to the String in the query
     filter: Option<Filter<'a>>,
     offset: usize,
@@ -40,6 +40,7 @@ impl<'a> Search<'a> {
     pub fn new(rtxn: &'a heed::RoTxn, index: &'a Index) -> Search<'a> {
         Search {
             query: None,
+            vector: None,
             filter: None,
             offset: 0,
             limit: 20,
@@ -58,6 +59,11 @@ impl<'a> Search<'a> {
         self
     }
 
+    pub fn vector(&mut self, vector: impl Into<Vec<f32>>) -> &mut Search<'a> {
+        self.vector = Some(vector.into());
+        self
+    }
+
     pub fn offset(&mut self, offset: usize) -> &mut Search<'a> {
         self.offset = offset;
         self
@@ -94,7 +100,7 @@ impl<'a> Search<'a> {
         self
     }
 
-    /// Forces the search to exhaustively compute the number of candidates,
+    /// Force the search to exhastivelly compute the number of candidates,
     /// this will increase the search time but allows finite pagination.
     pub fn exhaustive_number_hits(&mut self, exhaustive_number_hits: bool) -> &mut Search<'a> {
         self.exhaustive_number_hits = exhaustive_number_hits;
@@ -103,10 +109,11 @@ impl<'a> Search<'a> {
 
     pub fn execute(&self) -> Result<SearchResult> {
         let mut ctx = SearchContext::new(self.index, self.rtxn);
-        let PartialSearchResult { located_query_terms, candidates, documents_ids, document_scores } =
+        let PartialSearchResult { located_query_terms, candidates, documents_ids } =
             execute_search(
                 &mut ctx,
                 &self.query,
+                &self.vector,
                 self.terms_matching_strategy,
                 self.exhaustive_number_hits,
                 &self.filter,
@@ -125,7 +132,7 @@ impl<'a> Search<'a> {
             None => MatchingWords::default(),
         };
 
-        Ok(SearchResult { matching_words, candidates, document_scores, documents_ids })
+        Ok(SearchResult { matching_words, candidates, documents_ids })
     }
 }
 
@@ -133,6 +140,7 @@ impl fmt::Debug for Search<'_> {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         let Search {
             query,
+            vector: _,
             filter,
             offset,
             limit,
@@ -146,6 +154,7 @@ impl fmt::Debug for Search<'_> {
         } = self;
         f.debug_struct("Search")
             .field("query", query)
+            .field("vector", &"[...]")
             .field("filter", filter)
             .field("offset", offset)
             .field("limit", limit)
@@ -161,8 +170,8 @@ impl fmt::Debug for Search<'_> {
 pub struct SearchResult {
     pub matching_words: MatchingWords,
     pub candidates: RoaringBitmap,
+    // TODO those documents ids should be associated with their criteria scores.
     pub documents_ids: Vec<DocumentId>,
-    pub document_scores: Vec<Vec<ScoreDetails>>,
 }
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]

milli/src/search/new/bucket_sort.rs

@@ -3,13 +3,11 @@ use roaring::RoaringBitmap;
 use super::logger::SearchLogger;
 use super::ranking_rules::{BoxRankingRule, RankingRuleQueryTrait};
 use super::SearchContext;
-use crate::score_details::ScoreDetails;
 use crate::search::new::distinct::{apply_distinct_rule, distinct_single_docid, DistinctOutput};
 use crate::Result;
 
 pub struct BucketSortOutput {
     pub docids: Vec<u32>,
-    pub scores: Vec<Vec<ScoreDetails>>,
     pub all_candidates: RoaringBitmap,
 }
 
@@ -33,11 +31,7 @@ pub fn bucket_sort<'ctx, Q: RankingRuleQueryTrait>(
     };
 
     if universe.len() < from as u64 {
-        return Ok(BucketSortOutput {
-            docids: vec![],
-            scores: vec![],
-            all_candidates: universe.clone(),
-        });
+        return Ok(BucketSortOutput { docids: vec![], all_candidates: universe.clone() });
     }
     if ranking_rules.is_empty() {
         if let Some(distinct_fid) = distinct_fid {
@@ -55,32 +49,22 @@ pub fn bucket_sort<'ctx, Q: RankingRuleQueryTrait>(
             }
             let mut all_candidates = universe - excluded;
             all_candidates.extend(results.iter().copied());
-            return Ok(BucketSortOutput {
-                scores: vec![Default::default(); results.len()],
-                docids: results,
-                all_candidates,
-            });
+            return Ok(BucketSortOutput { docids: results, all_candidates });
         } else {
-            let docids: Vec<u32> = universe.iter().skip(from).take(length).collect();
-            return Ok(BucketSortOutput {
-                scores: vec![Default::default(); docids.len()],
-                docids,
-                all_candidates: universe.clone(),
-            });
+            let docids = universe.iter().skip(from).take(length).collect();
+            return Ok(BucketSortOutput { docids, all_candidates: universe.clone() });
         };
     }
 
     let ranking_rules_len = ranking_rules.len();
 
     logger.start_iteration_ranking_rule(0, ranking_rules[0].as_ref(), query, universe);
-
     ranking_rules[0].start_iteration(ctx, logger, universe, query)?;
 
-    let mut ranking_rule_scores: Vec<ScoreDetails> = vec![];
-
     let mut ranking_rule_universes: Vec<RoaringBitmap> =
         vec![RoaringBitmap::default(); ranking_rules_len];
     ranking_rule_universes[0] = universe.clone();
+
     let mut cur_ranking_rule_index = 0;
 
     /// Finish iterating over the current ranking rule, yielding
@@ -105,16 +89,11 @@ pub fn bucket_sort<'ctx, Q: RankingRuleQueryTrait>(
             } else {
                 cur_ranking_rule_index -= 1;
             }
-            // FIXME: check off by one
-            if ranking_rule_scores.len() > cur_ranking_rule_index {
-                ranking_rule_scores.pop();
-            }
         };
     }
 
     let mut all_candidates = universe.clone();
     let mut valid_docids = vec![];
-    let mut valid_scores = vec![];
     let mut cur_offset = 0usize;
 
     macro_rules! maybe_add_to_results {
@@ -125,23 +104,23 @@ pub fn bucket_sort<'ctx, Q: RankingRuleQueryTrait>(
                 length,
                 logger,
                 &mut valid_docids,
-                &mut valid_scores,
                 &mut all_candidates,
                 &mut ranking_rule_universes,
                 &mut ranking_rules,
                 cur_ranking_rule_index,
                 &mut cur_offset,
                 distinct_fid,
-                &ranking_rule_scores,
                 $candidates,
             )?;
         };
     }
 
     while valid_docids.len() < length {
-        // The universe for this bucket is zero, so we don't need to sort
-        // anything, just go back to the parent ranking rule.
-        if ranking_rule_universes[cur_ranking_rule_index].is_empty() {
+        // The universe for this bucket is zero or one element, so we don't need to sort
+        // anything, just extend the results and go back to the parent ranking rule.
+        if ranking_rule_universes[cur_ranking_rule_index].len() <= 1 {
+            let bucket = std::mem::take(&mut ranking_rule_universes[cur_ranking_rule_index]);
+            maybe_add_to_results!(bucket);
             back!();
             continue;
         }
@@ -151,8 +130,6 @@ pub fn bucket_sort<'ctx, Q: RankingRuleQueryTrait>(
             continue;
         };
 
-        ranking_rule_scores.push(next_bucket.score);
-
         logger.next_bucket_ranking_rule(
             cur_ranking_rule_index,
             ranking_rules[cur_ranking_rule_index].as_ref(),
@@ -166,11 +143,10 @@ pub fn bucket_sort<'ctx, Q: RankingRuleQueryTrait>(
         ranking_rule_universes[cur_ranking_rule_index] -= &next_bucket.candidates;
 
         if cur_ranking_rule_index == ranking_rules_len - 1
+            || next_bucket.candidates.len() <= 1
             || cur_offset + (next_bucket.candidates.len() as usize) < from
         {
             maybe_add_to_results!(next_bucket.candidates);
-            // FIXME: use index based logic like all the other rules so that you don't have to maintain the pop/push?
-            ranking_rule_scores.pop();
             continue;
         }
 
@@ -190,7 +166,7 @@ pub fn bucket_sort<'ctx, Q: RankingRuleQueryTrait>(
         )?;
     }
 
-    Ok(BucketSortOutput { docids: valid_docids, scores: valid_scores, all_candidates })
+    Ok(BucketSortOutput { docids: valid_docids, all_candidates })
 }
 
 /// Add the candidates to the results. Take `distinct`, `from`, `length`, and `cur_offset`
@@ -203,18 +179,14 @@ fn maybe_add_to_results<'ctx, Q: RankingRuleQueryTrait>(
     logger: &mut dyn SearchLogger<Q>,
 
     valid_docids: &mut Vec<u32>,
-    valid_scores: &mut Vec<Vec<ScoreDetails>>,
     all_candidates: &mut RoaringBitmap,
 
     ranking_rule_universes: &mut [RoaringBitmap],
     ranking_rules: &mut [BoxRankingRule<'ctx, Q>],
-
     cur_ranking_rule_index: usize,
 
     cur_offset: &mut usize,
-
     distinct_fid: Option<u16>,
-    ranking_rule_scores: &[ScoreDetails],
     candidates: RoaringBitmap,
 ) -> Result<()> {
     // First apply the distinct rule on the candidates, reducing the universes if necessary
@@ -259,17 +231,13 @@ fn maybe_add_to_results<'ctx, Q: RankingRuleQueryTrait>(
             let candidates =
                 candidates.iter().take(length - valid_docids.len()).copied().collect::<Vec<_>>();
             logger.add_to_results(&candidates);
-            valid_docids.extend_from_slice(&candidates);
-            valid_scores
-                .extend(std::iter::repeat(ranking_rule_scores.to_owned()).take(candidates.len()));
+            valid_docids.extend(&candidates);
         }
     } else {
         // if we have passed the offset already, add some of the documents (up to the limit)
         let candidates = candidates.iter().take(length - valid_docids.len()).collect::<Vec<u32>>();
         logger.add_to_results(&candidates);
-        valid_docids.extend_from_slice(&candidates);
-        valid_scores
-            .extend(std::iter::repeat(ranking_rule_scores.to_owned()).take(candidates.len()));
+        valid_docids.extend(&candidates);
     }
 
     *cur_offset += candidates.len() as usize;

milli/src/search/new/exact_attribute.rs

@@ -2,7 +2,6 @@ use roaring::{MultiOps, RoaringBitmap};
 
 use super::query_graph::QueryGraph;
 use super::ranking_rules::{RankingRule, RankingRuleOutput};
-use crate::score_details::{self, ScoreDetails};
 use crate::search::new::query_graph::QueryNodeData;
 use crate::search::new::query_term::ExactTerm;
 use crate::{Result, SearchContext, SearchLogger};
@@ -245,13 +244,7 @@ impl State {
                 candidates &= universe;
                 (
                     State::AttributeStarts(query_graph.clone(), candidates_per_attribute),
-                    Some(RankingRuleOutput {
-                        query: query_graph,
-                        candidates,
-                        score: ScoreDetails::ExactAttribute(
-                            score_details::ExactAttribute::MatchesFull,
-                        ),
-                    }),
+                    Some(RankingRuleOutput { query: query_graph, candidates }),
                 )
             }
             State::AttributeStarts(query_graph, candidates_per_attribute) => {
@@ -264,24 +257,12 @@ impl State {
                 candidates &= universe;
                 (
                     State::Empty(query_graph.clone()),
-                    Some(RankingRuleOutput {
-                        query: query_graph,
-                        candidates,
-                        score: ScoreDetails::ExactAttribute(
-                            score_details::ExactAttribute::MatchesStart,
-                        ),
-                    }),
+                    Some(RankingRuleOutput { query: query_graph, candidates }),
                 )
             }
             State::Empty(query_graph) => (
                 State::Empty(query_graph.clone()),
-                Some(RankingRuleOutput {
-                    query: query_graph,
-                    candidates: universe.clone(),
-                    score: ScoreDetails::ExactAttribute(
-                        score_details::ExactAttribute::NoExactMatch,
-                    ),
-                }),
+                Some(RankingRuleOutput { query: query_graph, candidates: universe.clone() }),
             ),
         };
         (state, output)

milli/src/search/new/geo_sort.rs

@@ -8,7 +8,6 @@ use rstar::RTree;
 
 use super::ranking_rules::{RankingRule, RankingRuleOutput, RankingRuleQueryTrait};
 use crate::heed_codec::facet::{FieldDocIdFacetCodec, OrderedF64Codec};
-use crate::score_details::{self, ScoreDetails};
 use crate::{
     distance_between_two_points, lat_lng_to_xyz, GeoPoint, Index, Result, SearchContext,
     SearchLogger,
@@ -81,7 +80,7 @@ pub struct GeoSort<Q: RankingRuleQueryTrait> {
     field_ids: Option<[u16; 2]>,
     rtree: Option<RTree<GeoPoint>>,
 
-    cached_sorted_docids: VecDeque<(u32, [f64; 2])>,
+    cached_sorted_docids: VecDeque<u32>,
     geo_candidates: RoaringBitmap,
 }
 
@@ -131,7 +130,7 @@ impl<Q: RankingRuleQueryTrait> GeoSort<Q> {
                 let point = lat_lng_to_xyz(&self.point);
                 for point in rtree.nearest_neighbor_iter(&point) {
                     if self.geo_candidates.contains(point.data.0) {
-                        self.cached_sorted_docids.push_back(point.data);
+                        self.cached_sorted_docids.push_back(point.data.0);
                         if self.cached_sorted_docids.len() >= cache_size {
                             break;
                         }
@@ -143,7 +142,7 @@ impl<Q: RankingRuleQueryTrait> GeoSort<Q> {
                 let point = lat_lng_to_xyz(&opposite_of(self.point));
                 for point in rtree.nearest_neighbor_iter(&point) {
                     if self.geo_candidates.contains(point.data.0) {
-                        self.cached_sorted_docids.push_front(point.data);
+                        self.cached_sorted_docids.push_front(point.data.0);
                         if self.cached_sorted_docids.len() >= cache_size {
                             break;
                         }
@@ -178,7 +177,7 @@ impl<Q: RankingRuleQueryTrait> GeoSort<Q> {
             // computing the distance between two points is expensive thus we cache the result
             documents
                 .sort_by_cached_key(|(_, p)| distance_between_two_points(&self.point, p) as usize);
-            self.cached_sorted_docids.extend(documents.into_iter());
+            self.cached_sorted_docids.extend(documents.into_iter().map(|(doc_id, _)| doc_id));
         };
 
         Ok(())
@@ -221,19 +220,12 @@ impl<'ctx, Q: RankingRuleQueryTrait> RankingRule<'ctx, Q> for GeoSort<Q> {
         logger: &mut dyn SearchLogger<Q>,
         universe: &RoaringBitmap,
     ) -> Result<Option<RankingRuleOutput<Q>>> {
+        assert!(universe.len() > 1);
         let query = self.query.as_ref().unwrap().clone();
         self.geo_candidates &= universe;
 
         if self.geo_candidates.is_empty() {
-            return Ok(Some(RankingRuleOutput {
-                query,
-                candidates: universe.clone(),
-                score: ScoreDetails::GeoSort(score_details::GeoSort {
-                    target_point: self.point,
-                    ascending: self.ascending,
-                    value: None,
-                }),
-            }));
+            return Ok(Some(RankingRuleOutput { query, candidates: universe.clone() }));
         }
 
         let ascending = self.ascending;
@@ -244,16 +236,11 @@ impl<'ctx, Q: RankingRuleQueryTrait> RankingRule<'ctx, Q> for GeoSort<Q> {
                 cache.pop_back()
             }
         };
-        while let Some((id, point)) = next(&mut self.cached_sorted_docids) {
+        while let Some(id) = next(&mut self.cached_sorted_docids) {
             if self.geo_candidates.contains(id) {
                 return Ok(Some(RankingRuleOutput {
                     query,
                     candidates: RoaringBitmap::from_iter([id]),
-                    score: ScoreDetails::GeoSort(score_details::GeoSort {
-                        target_point: self.point,
-                        ascending: self.ascending,
-                        value: Some(point),
-                    }),
                 }));
             }
         }

milli/src/search/new/graph_based_ranking_rule.rs

@@ -50,7 +50,6 @@ use super::ranking_rule_graph::{
 };
 use super::small_bitmap::SmallBitmap;
 use super::{QueryGraph, RankingRule, RankingRuleOutput, SearchContext};
-use crate::score_details::Rank;
 use crate::search::new::query_term::LocatedQueryTermSubset;
 use crate::search::new::ranking_rule_graph::PathVisitor;
 use crate::{Result, TermsMatchingStrategy};
@@ -119,8 +118,6 @@ pub struct GraphBasedRankingRuleState<G: RankingRuleGraphTrait> {
     all_costs: MappedInterner<QueryNode, Vec<u64>>,
     /// An index in the first element of `all_distances`, giving the cost of the next bucket
     cur_cost: u64,
-    /// One above the highest possible cost for this rule
-    next_max_cost: u64,
 }
 
 impl<'ctx, G: RankingRuleGraphTrait> RankingRule<'ctx, QueryGraph> for GraphBasedRankingRule<G> {
@@ -142,12 +139,13 @@ impl<'ctx, G: RankingRuleGraphTrait> RankingRule<'ctx, QueryGraph> for GraphBase
                     let mut forbidden_nodes =
                         SmallBitmap::for_interned_values_in(&query_graph.nodes);
                     let mut costs = query_graph.nodes.map(|_| None);
-                    // FIXME: this works because only words uses termsmatchingstrategy at the moment.
+                    let mut cost = 100;
                     for ns in removal_order {
                         for n in ns.iter() {
-                            *costs.get_mut(n) = Some((1, forbidden_nodes.clone()));
+                            *costs.get_mut(n) = Some((cost, forbidden_nodes.clone()));
                         }
                         forbidden_nodes.union(&ns);
+                        cost += 100;
                     }
                     costs
                 }
@@ -164,16 +162,12 @@ impl<'ctx, G: RankingRuleGraphTrait> RankingRule<'ctx, QueryGraph> for GraphBase
         // Then pre-compute the cost of all paths from each node to the end node
         let all_costs = graph.find_all_costs_to_end();
 
-        let next_max_cost =
-            all_costs.get(graph.query_graph.root_node).iter().copied().max().unwrap_or(0) + 1;
-
         let state = GraphBasedRankingRuleState {
             graph,
             conditions_cache: condition_docids_cache,
             dead_ends_cache,
             all_costs,
             cur_cost: 0,
-            next_max_cost,
         };
 
         self.state = Some(state);
@@ -187,13 +181,17 @@ impl<'ctx, G: RankingRuleGraphTrait> RankingRule<'ctx, QueryGraph> for GraphBase
         logger: &mut dyn SearchLogger<QueryGraph>,
         universe: &RoaringBitmap,
     ) -> Result<Option<RankingRuleOutput<QueryGraph>>> {
+        // If universe.len() <= 1, the bucket sort algorithm
+        // should not have called this function.
+        assert!(universe.len() > 1);
         // Will crash if `next_bucket` is called before `start_iteration` or after `end_iteration`,
         // should never happen
         let mut state = self.state.take().unwrap();
 
-        let all_costs = state.all_costs.get(state.graph.query_graph.root_node);
         // Retrieve the cost of the paths to compute
-        let Some(&cost) = all_costs
+        let Some(&cost) = state
+            .all_costs
+            .get(state.graph.query_graph.root_node)
             .iter()
             .find(|c| **c >= state.cur_cost) else {
                 self.state = None;
@@ -209,12 +207,8 @@ impl<'ctx, G: RankingRuleGraphTrait> RankingRule<'ctx, QueryGraph> for GraphBase
             dead_ends_cache,
             all_costs,
             cur_cost: _,
-            next_max_cost,
         } = &mut state;
 
-        let rank = *next_max_cost - cost;
-        let score = G::rank_to_score(Rank { rank: rank as u32, max_rank: *next_max_cost as u32 });
-
         let mut universe = universe.clone();
 
         let mut used_conditions = SmallBitmap::for_interned_values_in(&graph.conditions_interner);
@@ -331,7 +325,7 @@ impl<'ctx, G: RankingRuleGraphTrait> RankingRule<'ctx, QueryGraph> for GraphBase
 
         self.state = Some(state);
 
-        Ok(Some(RankingRuleOutput { query: next_query_graph, candidates: bucket, score }))
+        Ok(Some(RankingRuleOutput { query: next_query_graph, candidates: bucket }))
     }
 
     fn end_iteration(

milli/src/search/new/matches/mod.rs

@@ -509,6 +509,7 @@ mod tests {
             let crate::search::PartialSearchResult { located_query_terms, .. } = execute_search(
                 &mut ctx,
                 &Some(query.to_string()),
+                &None,
                 crate::TermsMatchingStrategy::default(),
                 false,
                 &None,

milli/src/search/new/mod.rs

@@ -28,6 +28,7 @@ use db_cache::DatabaseCache;
 use exact_attribute::ExactAttribute;
 use graph_based_ranking_rule::{Exactness, Fid, Position, Proximity, Typo};
 use heed::RoTxn;
+use hnsw::Searcher;
 use interner::{DedupInterner, Interner};
 pub use logger::visual::VisualSearchLogger;
 pub use logger::{DefaultSearchLogger, SearchLogger};
@@ -39,14 +40,16 @@ use ranking_rules::{
 use resolve_query_graph::{compute_query_graph_docids, PhraseDocIdsCache};
 use roaring::RoaringBitmap;
 use sort::Sort;
+use space::Neighbor;
 
 use self::geo_sort::GeoSort;
 pub use self::geo_sort::Strategy as GeoSortStrategy;
 use self::graph_based_ranking_rule::Words;
 use self::interner::Interned;
-use crate::score_details::ScoreDetails;
 use crate::search::new::distinct::apply_distinct_rule;
-use crate::{AscDesc, DocumentId, Filter, Index, Member, Result, TermsMatchingStrategy, UserError};
+use crate::{
+    AscDesc, DocumentId, Filter, Index, Member, Result, TermsMatchingStrategy, UserError, BEU32,
+};
 
 /// A structure used throughout the execution of a search query.
 pub struct SearchContext<'ctx> {
@@ -350,6 +353,7 @@ fn resolve_sort_criteria<'ctx, Query: RankingRuleQueryTrait>(
 pub fn execute_search(
     ctx: &mut SearchContext,
     query: &Option<String>,
+    vector: &Option<Vec<f32>>,
     terms_matching_strategy: TermsMatchingStrategy,
     exhaustive_number_hits: bool,
     filters: &Option<Filter>,
@@ -427,15 +431,40 @@ pub fn execute_search(
         )?
     };
 
-    let BucketSortOutput { docids, scores, mut all_candidates } = bucket_sort_output;
+    let BucketSortOutput { docids, mut all_candidates } = bucket_sort_output;
 
-    let fields_ids_map = ctx.index.fields_ids_map(ctx.txn)?;
+    let docids = match vector {
+        Some(vector) => {
+            // return the nearest documents that are also part of the candidates.
+            let mut searcher = Searcher::new();
+            let hnsw = ctx.index.vector_hnsw(ctx.txn)?.unwrap_or_default();
+            let ef = hnsw.len().min(100);
+            let mut dest = vec![Neighbor { index: 0, distance: 0 }; ef];
+            let neighbors = hnsw.nearest(vector, ef, &mut searcher, &mut dest[..]);
+
+            let mut docids = Vec::new();
+            for Neighbor { index, distance: _ } in neighbors.iter() {
+                let index = BEU32::new(*index as u32);
+                let docid = ctx.index.vector_id_docid.get(ctx.txn, &index)?.unwrap().get();
+                if universe.contains(docid) {
+                    docids.push(docid);
+                    if docids.len() == (from + length) {
+                        break;
+                    }
+                }
+            }
+
+            docids.into_iter().skip(from).take(length).collect()
+        }
+        // return the search docids if the vector field is not specified
+        None => docids,
+    };
 
     // The candidates is the universe unless the exhaustive number of hits
     // is requested and a distinct attribute is set.
     if exhaustive_number_hits {
         if let Some(f) = ctx.index.distinct_field(ctx.txn)? {
-            if let Some(distinct_fid) = fields_ids_map.id(f) {
+            if let Some(distinct_fid) = ctx.index.fields_ids_map(ctx.txn)?.id(f) {
                 all_candidates = apply_distinct_rule(ctx, distinct_fid, &all_candidates)?.remaining;
             }
         }
@@ -443,7 +472,6 @@ pub fn execute_search(
 
     Ok(PartialSearchResult {
         candidates: all_candidates,
-        document_scores: scores,
         documents_ids: docids,
         located_query_terms,
     })
@@ -495,5 +523,4 @@ pub struct PartialSearchResult {
     pub located_query_terms: Option<Vec<LocatedQueryTerm>>,
     pub candidates: RoaringBitmap,
     pub documents_ids: Vec<DocumentId>,
-    pub document_scores: Vec<Vec<ScoreDetails>>,
 }

milli/src/search/new/ranking_rule_graph/build.rs

@@ -49,15 +49,10 @@ impl<G: RankingRuleGraphTrait> RankingRuleGraph<G> {
                 if let Some((cost_of_ignoring, forbidden_nodes)) =
                     cost_of_ignoring_node.get(dest_idx)
                 {
-                    let dest = graph_nodes.get(dest_idx);
-                    let dest_size = match &dest.data {
-                        QueryNodeData::Term(term) => term.term_ids.len(),
-                        _ => panic!(),
-                    };
                     let new_edge_id = edges_store.insert(Some(Edge {
                         source_node: source_id,
                         dest_node: dest_idx,
-                        cost: *cost_of_ignoring * dest_size as u32,
+                        cost: *cost_of_ignoring,
                         condition: None,
                         nodes_to_skip: forbidden_nodes.clone(),
                     }));

milli/src/search/new/ranking_rule_graph/exactness/mod.rs

@@ -1,7 +1,6 @@
 use roaring::RoaringBitmap;
 
 use super::{ComputedCondition, RankingRuleGraphTrait};
-use crate::score_details::{Rank, ScoreDetails};
 use crate::search::new::interner::{DedupInterner, Interned};
 use crate::search::new::query_term::{ExactTerm, LocatedQueryTermSubset};
 use crate::search::new::resolve_query_graph::compute_query_term_subset_docids;
@@ -85,8 +84,4 @@ impl RankingRuleGraphTrait for ExactnessGraph {
 
         Ok(vec![(0, exact_condition), (dest_node.term_ids.len() as u32, skip_condition)])
     }
-
-    fn rank_to_score(rank: Rank) -> ScoreDetails {
-        ScoreDetails::Exactness(rank)
-    }
 }

milli/src/search/new/ranking_rule_graph/fid/mod.rs

@@ -2,7 +2,6 @@ use fxhash::FxHashSet;
 use roaring::RoaringBitmap;
 
 use super::{ComputedCondition, RankingRuleGraphTrait};
-use crate::score_details::{Rank, ScoreDetails};
 use crate::search::new::interner::{DedupInterner, Interned};
 use crate::search::new::query_term::LocatedQueryTermSubset;
 use crate::search::new::resolve_query_graph::compute_query_term_subset_docids_within_field_id;
@@ -69,7 +68,7 @@ impl RankingRuleGraphTrait for FidGraph {
         }
 
         let mut edges = vec![];
-        for fid in all_fields.iter().copied() {
+        for fid in all_fields {
             // TODO: We can improve performances and relevancy by storing
             //       the term subsets associated to each field ids fetched.
             edges.push((
@@ -81,35 +80,6 @@ impl RankingRuleGraphTrait for FidGraph {
             ));
         }
 
-        // always lookup the max_fid if we don't already and add an artificial condition for max scoring
-        let max_fid: Option<u16> = {
-            if let Some(max_fid) = ctx
-                .index
-                .searchable_fields_ids(ctx.txn)?
-                .map(|field_ids| field_ids.into_iter().max())
-            {
-                max_fid
-            } else {
-                ctx.index.fields_ids_map(ctx.txn)?.ids().max()
-            }
-        };
-
-        if let Some(max_fid) = max_fid {
-            if !all_fields.contains(&max_fid) {
-                edges.push((
-                    max_fid as u32 * term.term_ids.len() as u32, // TODO improve the fid score i.e. fid^10.
-                    conditions_interner.insert(FidCondition {
-                        term: term.clone(), // TODO remove this ugly clone
-                        fid: max_fid,
-                    }),
-                ));
-            }
-        }
-
         Ok(edges)
     }
-
-    fn rank_to_score(rank: Rank) -> ScoreDetails {
-        ScoreDetails::Fid(rank)
-    }
 }

milli/src/search/new/ranking_rule_graph/mod.rs

@@ -41,7 +41,6 @@ use super::interner::{DedupInterner, FixedSizeInterner, Interned, MappedInterner
 use super::query_term::LocatedQueryTermSubset;
 use super::small_bitmap::SmallBitmap;
 use super::{QueryGraph, QueryNode, SearchContext};
-use crate::score_details::{Rank, ScoreDetails};
 use crate::Result;
 
 pub struct ComputedCondition {
@@ -111,9 +110,6 @@ pub trait RankingRuleGraphTrait: Sized + 'static {
         source_node: Option<&LocatedQueryTermSubset>,
         dest_node: &LocatedQueryTermSubset,
     ) -> Result<Vec<(u32, Interned<Self::Condition>)>>;
-
-    /// Convert the rank of a path to its corresponding score for the ranking rule
-    fn rank_to_score(rank: Rank) -> ScoreDetails;
 }
 
 /// The graph used by graph-based ranking rules.

milli/src/search/new/ranking_rule_graph/position/mod.rs

@@ -2,7 +2,6 @@ use fxhash::{FxHashMap, FxHashSet};
 use roaring::RoaringBitmap;
 
 use super::{ComputedCondition, RankingRuleGraphTrait};
-use crate::score_details::{Rank, ScoreDetails};
 use crate::search::new::interner::{DedupInterner, Interned};
 use crate::search::new::query_term::LocatedQueryTermSubset;
 use crate::search::new::resolve_query_graph::compute_query_term_subset_docids_within_position;
@@ -106,20 +105,8 @@ impl RankingRuleGraphTrait for PositionGraph {
             ));
         }
 
-        // artificial empty condition for computing max cost
-        let max_cost = term.term_ids.len() as u32 * 10;
-        edges.push((
-            max_cost,
-            conditions_interner
-                .insert(PositionCondition { term: term.clone(), positions: Vec::default() }),
-        ));
-
         Ok(edges)
     }
-
-    fn rank_to_score(rank: Rank) -> ScoreDetails {
-        ScoreDetails::Position(rank)
-    }
 }
 
 fn cost_from_position(sum_positions: u32) -> u32 {

milli/src/search/new/ranking_rule_graph/proximity/mod.rs

@@ -4,7 +4,6 @@ pub mod compute_docids;
 use roaring::RoaringBitmap;
 
 use super::{ComputedCondition, RankingRuleGraphTrait};
-use crate::score_details::{Rank, ScoreDetails};
 use crate::search::new::interner::{DedupInterner, Interned};
 use crate::search::new::query_term::LocatedQueryTermSubset;
 use crate::search::new::SearchContext;
@@ -37,8 +36,4 @@ impl RankingRuleGraphTrait for ProximityGraph {
     ) -> Result<Vec<(u32, Interned<Self::Condition>)>> {
         build::build_edges(ctx, conditions_interner, source_term, dest_term)
     }
-
-    fn rank_to_score(rank: Rank) -> ScoreDetails {
-        ScoreDetails::Proximity(rank)
-    }
 }

milli/src/search/new/ranking_rule_graph/typo/mod.rs

@@ -1,7 +1,6 @@
 use roaring::RoaringBitmap;
 
 use super::{ComputedCondition, RankingRuleGraphTrait};
-use crate::score_details::{self, Rank, ScoreDetails};
 use crate::search::new::interner::{DedupInterner, Interned};
 use crate::search::new::query_term::LocatedQueryTermSubset;
 use crate::search::new::resolve_query_graph::compute_query_term_subset_docids;
@@ -76,8 +75,4 @@ impl RankingRuleGraphTrait for TypoGraph {
         }
         Ok(edges)
     }
-
-    fn rank_to_score(rank: Rank) -> ScoreDetails {
-        ScoreDetails::Typo(score_details::Typo::from_rank(rank))
-    }
 }

milli/src/search/new/ranking_rule_graph/words/mod.rs

@@ -1,7 +1,6 @@
 use roaring::RoaringBitmap;
 
 use super::{ComputedCondition, RankingRuleGraphTrait};
-use crate::score_details::{self, Rank, ScoreDetails};
 use crate::search::new::interner::{DedupInterner, Interned};
 use crate::search::new::query_term::LocatedQueryTermSubset;
 use crate::search::new::resolve_query_graph::compute_query_term_subset_docids;
@@ -42,10 +41,9 @@ impl RankingRuleGraphTrait for WordsGraph {
         _from: Option<&LocatedQueryTermSubset>,
         to_term: &LocatedQueryTermSubset,
     ) -> Result<Vec<(u32, Interned<Self::Condition>)>> {
-        Ok(vec![(0, conditions_interner.insert(WordsCondition { term: to_term.clone() }))])
-    }
-
-    fn rank_to_score(rank: Rank) -> ScoreDetails {
-        ScoreDetails::Words(score_details::Words::from_rank(rank))
+        Ok(vec![(
+            to_term.term_ids.len() as u32,
+            conditions_interner.insert(WordsCondition { term: to_term.clone() }),
+        )])
     }
 }

milli/src/search/new/ranking_rules.rs

@@ -2,7 +2,6 @@ use roaring::RoaringBitmap;
 
 use super::logger::SearchLogger;
 use super::{QueryGraph, SearchContext};
-use crate::score_details::ScoreDetails;
 use crate::Result;
 
 /// An internal trait implemented by only [`PlaceholderQuery`] and [`QueryGraph`]
@@ -67,6 +66,4 @@ pub struct RankingRuleOutput<Q> {
     pub query: Q,
     /// The allowed candidates for the child ranking rule
     pub candidates: RoaringBitmap,
-    /// The score for the candidates of the current bucket
-    pub score: ScoreDetails,
 }

milli/src/search/new/sort.rs

@@ -1,11 +1,9 @@
-use heed::BytesDecode;
 use roaring::RoaringBitmap;
 
 use super::logger::SearchLogger;
 use super::{RankingRule, RankingRuleOutput, RankingRuleQueryTrait, SearchContext};
-use crate::heed_codec::facet::{FacetGroupKeyCodec, OrderedF64Codec};
-use crate::heed_codec::{ByteSliceRefCodec, StrRefCodec};
-use crate::score_details::{self, ScoreDetails};
+use crate::heed_codec::facet::FacetGroupKeyCodec;
+use crate::heed_codec::ByteSliceRefCodec;
 use crate::search::facet::{ascending_facet_sort, descending_facet_sort};
 use crate::{FieldId, Index, Result};
 
@@ -69,7 +67,7 @@ impl<'ctx, Query> Sort<'ctx, Query> {
 impl<'ctx, Query: RankingRuleQueryTrait> RankingRule<'ctx, Query> for Sort<'ctx, Query> {
     fn id(&self) -> String {
         let Self { field_name, is_ascending, .. } = self;
-        format!("{field_name}:{}", if *is_ascending { "asc" } else { "desc" })
+        format!("{field_name}:{}", if *is_ascending { "asc" } else { "desc " })
     }
     fn start_iteration(
         &mut self,
@@ -120,43 +118,12 @@ impl<'ctx, Query: RankingRuleQueryTrait> RankingRule<'ctx, Query> for Sort<'ctx,
 
                     (itertools::Either::Right(number_iter), itertools::Either::Right(string_iter))
                 };
-                let number_iter = number_iter.map(|r| -> Result<_> {
-                    let (docids, bytes) = r?;
-                    Ok((
-                        docids,
-                        serde_json::Value::Number(
-                            serde_json::Number::from_f64(
-                                OrderedF64Codec::bytes_decode(bytes).expect("some number"),
-                            )
-                            .expect("too big float"),
-                        ),
-                    ))
-                });
-                let string_iter = string_iter.map(|r| -> Result<_> {
-                    let (docids, bytes) = r?;
-                    Ok((
-                        docids,
-                        serde_json::Value::String(
-                            StrRefCodec::bytes_decode(bytes).expect("some string").to_owned(),
-                        ),
-                    ))
-                });
 
                 let query_graph = parent_query.clone();
-                let ascending = self.is_ascending;
-                let field_name = self.field_name.clone();
                 RankingRuleOutputIterWrapper::new(Box::new(number_iter.chain(string_iter).map(
                     move |r| {
-                        let (docids, value) = r?;
-                        Ok(RankingRuleOutput {
-                            query: query_graph.clone(),
-                            candidates: docids,
-                            score: ScoreDetails::Sort(score_details::Sort {
-                                field_name: field_name.clone(),
-                                ascending,
-                                value,
-                            }),
-                        })
+                        let (docids, _) = r?;
+                        Ok(RankingRuleOutput { query: query_graph.clone(), candidates: docids })
                     },
                 )))
             }
@@ -183,15 +150,7 @@ impl<'ctx, Query: RankingRuleQueryTrait> RankingRule<'ctx, Query> for Sort<'ctx,
             Ok(Some(bucket))
         } else {
             let query = self.original_query.as_ref().unwrap().clone();
-            Ok(Some(RankingRuleOutput {
-                query,
-                candidates: universe.clone(),
-                score: ScoreDetails::Sort(score_details::Sort {
-                    field_name: self.field_name.clone(),
-                    ascending: self.is_ascending,
-                    value: serde_json::Value::Null,
-                }),
-            }))
+            Ok(Some(RankingRuleOutput { query, candidates: universe.clone() }))
         }
     }
 

milli/src/snapshot_tests.rs

@@ -318,7 +318,7 @@ pub fn snap_field_distributions(index: &Index) -> String {
     let rtxn = index.read_txn().unwrap();
     let mut snap = String::new();
     for (field, count) in index.field_distribution(&rtxn).unwrap() {
-        writeln!(&mut snap, "{field:<16} {count:<6}").unwrap();
+        writeln!(&mut snap, "{field:<16} {count:<6} |").unwrap();
     }
     snap
 }
@@ -328,7 +328,7 @@ pub fn snap_fields_ids_map(index: &Index) -> String {
     let mut snap = String::new();
     for field_id in fields_ids_map.ids() {
         let name = fields_ids_map.name(field_id).unwrap();
-        writeln!(&mut snap, "{field_id:<3} {name:<16}").unwrap();
+        writeln!(&mut snap, "{field_id:<3} {name:<16} |").unwrap();
     }
     snap
 }

milli/src/snapshots/index.rs/initial_field_distribution/1/field_distribution.snap

@@ -1,7 +1,7 @@
 ---
 source: milli/src/index.rs
 ---
-age              1     
-id               2     
-name             2     
+age              1      |
+id               2      |
+name             2      |
 

milli/src/snapshots/index.rs/initial_field_distribution/field_distribution.snap

@@ -1,7 +1,7 @@
 ---
 source: milli/src/index.rs
 ---
-age              1     
-id               2     
-name             2     
+age              1      |
+id               2      |
+name             2      |
 

milli/src/update/clear_documents.rs

@@ -39,6 +39,7 @@ impl<'t, 'u, 'i> ClearDocuments<'t, 'u, 'i> {
             facet_id_is_empty_docids,
             field_id_docid_facet_f64s,
             field_id_docid_facet_strings,
+            vector_id_docid,
             documents,
         } = self.index;
 
@@ -57,6 +58,7 @@ impl<'t, 'u, 'i> ClearDocuments<'t, 'u, 'i> {
         self.index.put_field_distribution(self.wtxn, &FieldDistribution::default())?;
         self.index.delete_geo_rtree(self.wtxn)?;
         self.index.delete_geo_faceted_documents_ids(self.wtxn)?;
+        self.index.delete_vector_hnsw(self.wtxn)?;
 
         // We clean all the faceted documents ids.
         for field_id in faceted_fields {
@@ -95,6 +97,7 @@ impl<'t, 'u, 'i> ClearDocuments<'t, 'u, 'i> {
         facet_id_string_docids.clear(self.wtxn)?;
         field_id_docid_facet_f64s.clear(self.wtxn)?;
         field_id_docid_facet_strings.clear(self.wtxn)?;
+        vector_id_docid.clear(self.wtxn)?;
         documents.clear(self.wtxn)?;
 
         Ok(number_of_documents)

milli/src/update/delete_documents.rs

@@ -4,8 +4,10 @@ use std::collections::{BTreeSet, HashMap, HashSet};
 use fst::IntoStreamer;
 use heed::types::{ByteSlice, DecodeIgnore, Str, UnalignedSlice};
 use heed::{BytesDecode, BytesEncode, Database, RwIter};
+use hnsw::Searcher;
 use roaring::RoaringBitmap;
 use serde::{Deserialize, Serialize};
+use space::KnnPoints;
 use time::OffsetDateTime;
 
 use super::facet::delete::FacetsDelete;
@@ -14,6 +16,7 @@ use crate::error::InternalError;
 use crate::facet::FacetType;
 use crate::heed_codec::facet::FieldDocIdFacetCodec;
 use crate::heed_codec::CboRoaringBitmapCodec;
+use crate::index::Hnsw;
 use crate::{
     ExternalDocumentsIds, FieldId, FieldIdMapMissingEntry, Index, Result, RoaringBitmapCodec, BEU32,
 };
@@ -247,6 +250,7 @@ impl<'t, 'u, 'i> DeleteDocuments<'t, 'u, 'i> {
             facet_id_exists_docids,
             facet_id_is_null_docids,
             facet_id_is_empty_docids,
+            vector_id_docid,
             documents,
         } = self.index;
         // Remove from the documents database
@@ -436,6 +440,30 @@ impl<'t, 'u, 'i> DeleteDocuments<'t, 'u, 'i> {
             &self.to_delete_docids,
         )?;
 
+        // An ugly and slow way to remove the vectors from the HNSW
+        // It basically reconstructs the HNSW from scratch without editing the current one.
+        let current_hnsw = self.index.vector_hnsw(self.wtxn)?.unwrap_or_default();
+        if !current_hnsw.is_empty() {
+            let mut new_hnsw = Hnsw::default();
+            let mut searcher = Searcher::new();
+            let mut new_vector_id_docids = Vec::new();
+
+            for result in vector_id_docid.iter(self.wtxn)? {
+                let (vector_id, docid) = result?;
+                if !self.to_delete_docids.contains(docid.get()) {
+                    let vector = current_hnsw.get_point(vector_id.get() as usize).clone();
+                    let vector_id = new_hnsw.insert(vector, &mut searcher);
+                    new_vector_id_docids.push((vector_id as u32, docid));
+                }
+            }
+
+            vector_id_docid.clear(self.wtxn)?;
+            for (vector_id, docid) in new_vector_id_docids {
+                vector_id_docid.put(self.wtxn, &BEU32::new(vector_id), &docid)?;
+            }
+            self.index.put_vector_hnsw(self.wtxn, &new_hnsw)?;
+        }
+
         self.index.put_soft_deleted_documents_ids(self.wtxn, &RoaringBitmap::new())?;
 
         Ok(DetailedDocumentDeletionResult {

milli/src/update/index_documents/extract/extract_vector_points.rs

@@ -0,0 +1,40 @@
+use std::fs::File;
+use std::io;
+
+use bytemuck::cast_slice;
+use serde_json::from_slice;
+
+use super::helpers::{create_writer, writer_into_reader, GrenadParameters};
+use crate::{FieldId, InternalError, Result};
+
+/// Extracts the embedding vector contained in each document under the `_vector` field.
+///
+/// Returns the generated grenad reader containing the docid as key associated to the Vec<f32>
+#[logging_timer::time]
+pub fn extract_vector_points<R: io::Read + io::Seek>(
+    obkv_documents: grenad::Reader<R>,
+    indexer: GrenadParameters,
+    vector_fid: FieldId,
+) -> Result<grenad::Reader<File>> {
+    let mut writer = create_writer(
+        indexer.chunk_compression_type,
+        indexer.chunk_compression_level,
+        tempfile::tempfile()?,
+    );
+
+    let mut cursor = obkv_documents.into_cursor()?;
+    while let Some((docid_bytes, value)) = cursor.move_on_next()? {
+        let obkv = obkv::KvReader::new(value);
+
+        // first we get the _vector field
+        if let Some(vector) = obkv.get(vector_fid) {
+            // try to extract the vector
+            let vector: Vec<f32> = from_slice(vector).map_err(InternalError::SerdeJson).unwrap();
+            let bytes = cast_slice(&vector);
+            writer.insert(docid_bytes, bytes)?;
+        }
+        // else => the _vector object was `null`, there is nothing to do
+    }
+
+    writer_into_reader(writer)
+}

milli/src/update/index_documents/extract/mod.rs

@@ -4,6 +4,7 @@ mod extract_facet_string_docids;
 mod extract_fid_docid_facet_values;
 mod extract_fid_word_count_docids;
 mod extract_geo_points;
+mod extract_vector_points;
 mod extract_word_docids;
 mod extract_word_fid_docids;
 mod extract_word_pair_proximity_docids;
@@ -22,6 +23,7 @@ use self::extract_facet_string_docids::extract_facet_string_docids;
 use self::extract_fid_docid_facet_values::{extract_fid_docid_facet_values, ExtractedFacetValues};
 use self::extract_fid_word_count_docids::extract_fid_word_count_docids;
 use self::extract_geo_points::extract_geo_points;
+use self::extract_vector_points::extract_vector_points;
 use self::extract_word_docids::extract_word_docids;
 use self::extract_word_fid_docids::extract_word_fid_docids;
 use self::extract_word_pair_proximity_docids::extract_word_pair_proximity_docids;
@@ -45,6 +47,7 @@ pub(crate) fn data_from_obkv_documents(
     faceted_fields: HashSet<FieldId>,
     primary_key_id: FieldId,
     geo_fields_ids: Option<(FieldId, FieldId)>,
+    vector_field_id: Option<FieldId>,
     stop_words: Option<fst::Set<&[u8]>>,
     max_positions_per_attributes: Option<u32>,
     exact_attributes: HashSet<FieldId>,
@@ -69,6 +72,7 @@ pub(crate) fn data_from_obkv_documents(
                     &faceted_fields,
                     primary_key_id,
                     geo_fields_ids,
+                    vector_field_id,
                     &stop_words,
                     max_positions_per_attributes,
                 )
@@ -279,6 +283,7 @@ fn send_and_extract_flattened_documents_data(
     faceted_fields: &HashSet<FieldId>,
     primary_key_id: FieldId,
     geo_fields_ids: Option<(FieldId, FieldId)>,
+    vector_field_id: Option<FieldId>,
     stop_words: &Option<fst::Set<&[u8]>>,
     max_positions_per_attributes: Option<u32>,
 ) -> Result<(
@@ -307,6 +312,20 @@ fn send_and_extract_flattened_documents_data(
         });
     }
 
+    if let Some(vector_field_id) = vector_field_id {
+        let documents_chunk_cloned = flattened_documents_chunk.clone();
+        let lmdb_writer_sx_cloned = lmdb_writer_sx.clone();
+        rayon::spawn(move || {
+            let result = extract_vector_points(documents_chunk_cloned, indexer, vector_field_id);
+            let _ = match result {
+                Ok(vector_points) => {
+                    lmdb_writer_sx_cloned.send(Ok(TypedChunk::VectorPoints(vector_points)))
+                }
+                Err(error) => lmdb_writer_sx_cloned.send(Err(error)),
+            };
+        });
+    }
+
     let (docid_word_positions_chunk, docid_fid_facet_values_chunks): (Result<_>, Result<_>) =
         rayon::join(
             || {

milli/src/update/index_documents/mod.rs

@@ -304,6 +304,8 @@ where
             }
             None => None,
         };
+        // get the fid of the `_vector` field.
+        let vector_field_id = self.index.fields_ids_map(self.wtxn)?.id("_vector");
 
         let stop_words = self.index.stop_words(self.wtxn)?;
         let exact_attributes = self.index.exact_attributes_ids(self.wtxn)?;
@@ -340,6 +342,7 @@ where
                     faceted_fields,
                     primary_key_id,
                     geo_fields_ids,
+                    vector_field_id,
                     stop_words,
                     max_positions_per_attributes,
                     exact_attributes,

milli/src/update/index_documents/typed_chunk.rs

@@ -4,20 +4,24 @@ use std::convert::TryInto;
 use std::fs::File;
 use std::io;
 
+use bytemuck::allocation::pod_collect_to_vec;
 use charabia::{Language, Script};
 use grenad::MergerBuilder;
 use heed::types::ByteSlice;
 use heed::RwTxn;
+use hnsw::Searcher;
 use roaring::RoaringBitmap;
+use space::KnnPoints;
 
 use super::helpers::{
     self, merge_ignore_values, serialize_roaring_bitmap, valid_lmdb_key, CursorClonableMmap,
 };
 use super::{ClonableMmap, MergeFn};
+use crate::error::UserError;
 use crate::facet::FacetType;
 use crate::update::facet::FacetsUpdate;
 use crate::update::index_documents::helpers::as_cloneable_grenad;
-use crate::{lat_lng_to_xyz, CboRoaringBitmapCodec, DocumentId, GeoPoint, Index, Result};
+use crate::{lat_lng_to_xyz, CboRoaringBitmapCodec, DocumentId, GeoPoint, Index, Result, BEU32};
 
 pub(crate) enum TypedChunk {
     FieldIdDocidFacetStrings(grenad::Reader<CursorClonableMmap>),
@@ -38,6 +42,7 @@ pub(crate) enum TypedChunk {
     FieldIdFacetIsNullDocids(grenad::Reader<File>),
     FieldIdFacetIsEmptyDocids(grenad::Reader<File>),
     GeoPoints(grenad::Reader<File>),
+    VectorPoints(grenad::Reader<File>),
     ScriptLanguageDocids(HashMap<(Script, Language), RoaringBitmap>),
 }
 
@@ -221,6 +226,38 @@ pub(crate) fn write_typed_chunk_into_index(
             index.put_geo_rtree(wtxn, &rtree)?;
             index.put_geo_faceted_documents_ids(wtxn, &geo_faceted_docids)?;
         }
+        TypedChunk::VectorPoints(vector_points) => {
+            let mut hnsw = index.vector_hnsw(wtxn)?.unwrap_or_default();
+            let mut searcher = Searcher::new();
+
+            let mut expected_dimensions = match index.vector_id_docid.iter(wtxn)?.next() {
+                Some(result) => {
+                    let (vector_id, _) = result?;
+                    Some(hnsw.get_point(vector_id.get() as usize).len())
+                }
+                None => None,
+            };
+
+            let mut cursor = vector_points.into_cursor()?;
+            while let Some((key, value)) = cursor.move_on_next()? {
+                // convert the key back to a u32 (4 bytes)
+                let docid = key.try_into().map(DocumentId::from_be_bytes).unwrap();
+                // convert the vector back to a Vec<f32>
+                let vector: Vec<f32> = pod_collect_to_vec(value);
+
+                // TODO Move this error in the vector extractor
+                let found = vector.len();
+                let expected = *expected_dimensions.get_or_insert(found);
+                if expected != found {
+                    return Err(UserError::InvalidVectorDimensions { expected, found })?;
+                }
+
+                let vector_id = hnsw.insert(vector, &mut searcher) as u32;
+                index.vector_id_docid.put(wtxn, &BEU32::new(vector_id), &BEU32::new(docid))?;
+            }
+            log::debug!("There are {} entries in the HNSW so far", hnsw.len());
+            index.put_vector_hnsw(wtxn, &hnsw)?;
+        }
         TypedChunk::ScriptLanguageDocids(hash_pair) => {
             let mut buffer = Vec::new();
             for (key, value) in hash_pair {