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Code Issues Releases Wiki Activity

feat: Introduce the QueryEnhancer in the query synonym system

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This commit is contained in:
Clément Renault 2019-07-07 20:27:37 +02:00
parent 5e691c2140
commit f478bbf826
1 changed files with 54 additions and 34 deletions
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88
meilidb-core/src/query_builder.rs
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@ -14,8 +14,9 @@ use sdset::SetBuf;
use slice_group_by::GroupByMut;
use crate::automaton::{build_dfa, build_prefix_dfa};
use crate::distinct_map::{DistinctMap, BufferedDistinctMap};
use crate::criterion::Criteria;
use crate::distinct_map::{DistinctMap, BufferedDistinctMap};
use crate::query_enhancer::{QueryEnhancerBuilder, QueryEnhancer};
use crate::raw_documents_from_matches;
use crate::reordered_attrs::ReorderedAttrs;
use crate::{TmpMatch, Highlight, DocumentId, Store, RawDocument, Document};
@ -91,18 +92,36 @@ fn split_best_frequency<'a, S: Store>(
Ok(best.map(|(_, l, r)| (l, r)))
}
fn generate_automatons<S: Store>(query: &str, store: &S) -> Result<Vec<Automaton>, S::Error> {
fn generate_automatons<S: Store>(query: &str, store: &S) -> Result<(Vec<Automaton>, QueryEnhancer), S::Error> {
let has_end_whitespace = query.chars().last().map_or(false, char::is_whitespace);
let query_words: Vec<_> = split_query_string(query).map(str::to_lowercase).collect();
let mut automatons = Vec::new();
let synonyms = store.synonyms()?;
for n in 1..=NGRAMS {
let mut query_index = 0;
let mut ngrams = query_words.windows(n).peekable();
let mut automatons = Vec::new();
let mut enhancer_builder = QueryEnhancerBuilder::new(&query_words);
while let Some(ngram_slice) = ngrams.next() {
// We must not declare the original words to the query enhancer
// *but* we need to push them in the automatons list first
let mut original_words = query_words.iter().enumerate().peekable();
while let Some((query_index, word)) = original_words.next() {
let has_following_word = original_words.peek().is_some();
let not_prefix_dfa = has_following_word || has_end_whitespace || word.chars().all(is_cjk);
let automaton = if not_prefix_dfa {
Automaton::exact(query_index, word)
} else {
Automaton::prefix_exact(query_index, word)
};
automatons.push(automaton);
}
for n in 1..=NGRAMS {
let mut ngrams = query_words.windows(n).enumerate().peekable();
while let Some((query_index, ngram_slice)) = ngrams.next() {
let query_range = query_index..query_index + n;
let ngram_nb_words = ngram_slice.len();
let ngram = ngram_slice.join(" ");
@ -127,15 +146,19 @@ fn generate_automatons<S: Store>(query: &str, store: &S) -> Result<Vec<Automaton
let mut stream = synonyms.into_stream();
while let Some(synonyms) = stream.next() {
let synonyms = std::str::from_utf8(synonyms).unwrap();
let nb_synonym_words = split_query_string(synonyms).count();
let synonyms_words: Vec<_> = split_query_string(synonyms).collect();
let nb_synonym_words = synonyms_words.len();
for synonym in split_query_string(synonyms) {
let real_query_index = automatons.len();
enhancer_builder.declare(query_range.clone(), real_query_index, &synonyms_words);
for (i, synonym) in synonyms_words.into_iter().enumerate() {
let automaton = if nb_synonym_words == 1 {
Automaton::exact(query_index, synonym)
Automaton::exact(real_query_index + i, synonym)
} else {
Automaton::non_exact(query_index, synonym)
Automaton::non_exact(real_query_index + i, synonym)
};
automatons.push((automaton, synonym.to_owned()));
automatons.push(automaton);
}
}
}
@ -145,37 +168,34 @@ fn generate_automatons<S: Store>(query: &str, store: &S) -> Result<Vec<Automaton
// TODO we do not support "phrase query" in other words:
// first term *must* follow the second term
if let Some((left, right)) = split_best_frequency(&ngram, store)? {
let automaton = Automaton::exact(query_index, left);
automatons.push((automaton, left.to_owned()));
let automaton = Automaton::exact(query_index, right);
automatons.push((automaton, right.to_owned()));
let real_query_index = automatons.len();
enhancer_builder.declare(query_range.clone(), real_query_index, &[left, right]);
// TODO must mark it as "phrase query"
// (the next match must follow its query index)
let automaton = Automaton::exact(real_query_index, left);
automatons.push(automaton);
let automaton = Automaton::exact(real_query_index + 1, right);
automatons.push(automaton);
}
let automaton = if not_prefix_dfa {
Automaton::exact(query_index, &ngram)
} else {
Automaton::prefix_exact(query_index, &ngram)
};
automatons.push((automaton, ngram));
} else {
// automaton of concatenation of query words
let concat = ngram_slice.concat();
let normalized = normalize_str(&concat);
let automaton = Automaton::exact(query_index, &normalized);
automatons.push((automaton, normalized));
}
query_index += 1;
let real_query_index = automatons.len();
enhancer_builder.declare(query_range.clone(), real_query_index, &[&normalized]);
let automaton = Automaton::exact(real_query_index, &normalized);
automatons.push(automaton);
}
}
}
automatons.sort_unstable_by(|a, b| (a.0.query_index, &a.1).cmp(&(b.0.query_index, &b.1)));
automatons.dedup_by(|a, b| (a.0.query_index, &a.1) == (b.0.query_index, &b.1));
let automatons = automatons.into_iter().map(|(a, _)| a).collect();
Ok(automatons)
Ok((automatons, enhancer_builder.build()))
}
fn rewrite_matched_positions(matches: &mut [(DocumentId, TmpMatch, Highlight)]) {
@ -238,7 +258,7 @@ impl<'c, S, FI> QueryBuilder<'c, S, FI>
where S: Store,
{
fn query_all(&self, query: &str) -> Result<Vec<RawDocument>, S::Error> {
let automatons = generate_automatons(query, &self.store)?;
let (automatons, query_enhancer) = generate_automatons(query, &self.store)?;
let words = self.store.words()?.as_fst();
let searchables = self.searchable_attrs.as_ref();