WIP on split words and synonyms support

This commit is contained in:
Loïc Lecrenier 2023-03-02 21:27:57 +01:00
parent c27ea2677f
commit 1db152046e
5 changed files with 233 additions and 142 deletions

View File

@ -31,22 +31,27 @@ pub fn make_query_graph<'transaction>(
query: &str,
) -> Result<QueryGraph> {
assert!(!query.is_empty());
let fst = index.words_fst(txn).unwrap();
let query = LocatedQueryTerm::from_query(query.tokenize(), None, |word, is_prefix| {
word_derivations(
index,
txn,
word,
if word.len() < 4 {
let authorize_typos = index.authorize_typos(txn)?;
let min_len_one_typo = index.min_word_len_one_typo(txn)?;
let min_len_two_typos = index.min_word_len_two_typos(txn)?;
let exact_words = index.exact_words(txn)?;
let fst = index.words_fst(txn)?;
// TODO: get rid of this closure
// also, ngrams can have one typo?
let query = LocatedQueryTerm::from_query(query.tokenize(), None, move |word, is_prefix| {
let typos = if !authorize_typos
|| word.len() < min_len_one_typo as usize
|| exact_words.as_ref().map_or(false, |fst| fst.contains(word))
{
0
} else if word.len() < 100 {
} else if word.len() < min_len_two_typos as usize {
1
} else {
2
},
is_prefix,
&fst,
)
};
word_derivations(index, txn, word, typos, is_prefix, &fst)
})
.unwrap();
let graph = QueryGraph::from_query(index, txn, db_cache, query)?;

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@ -7,7 +7,7 @@ use super::db_cache::DatabaseCache;
use super::query_term::{LocatedQueryTerm, QueryTerm, WordDerivations};
use crate::{Index, Result};
#[derive(Clone)]
#[derive(Debug, Clone)]
pub enum QueryNode {
Term(LocatedQueryTerm),
Deleted,
@ -31,7 +31,7 @@ pub struct QueryGraph {
}
fn _assert_sizes() {
let _: [u8; 112] = [0; std::mem::size_of::<QueryNode>()];
let _: [u8; 184] = [0; std::mem::size_of::<QueryNode>()];
let _: [u8; 48] = [0; std::mem::size_of::<Edges>()];
}
@ -116,6 +116,8 @@ impl QueryGraph {
one_typo: vec![],
two_typos: vec![],
use_prefix_db: false,
synonyms: vec![], // TODO: ngram synonyms
split_words: None, // TODO: maybe ngram split words?
},
},
positions: ngram2_pos,
@ -141,6 +143,8 @@ impl QueryGraph {
one_typo: vec![],
two_typos: vec![],
use_prefix_db: false,
synonyms: vec![], // TODO: ngram synonyms
split_words: None, // TODO: maybe ngram split words?
},
},
positions: ngram3_pos,
@ -188,19 +192,20 @@ impl QueryGraph {
Edges { predecessors: RoaringBitmap::new(), successors: RoaringBitmap::new() };
}
}
pub fn remove_words_at_position(&mut self, position: i8) {
pub fn remove_words_at_position(&mut self, position: i8) -> bool {
let mut nodes_to_remove_keeping_edges = vec![];
for (node_idx, node) in self.nodes.iter().enumerate() {
let node_idx = node_idx as u32;
let QueryNode::Term(LocatedQueryTerm { value: _, positions }) = node else { continue };
if positions.start() == &position {
nodes_to_remove_keeping_edges.push(node_idx)
nodes_to_remove_keeping_edges.push(node_idx);
}
}
self.remove_nodes_keep_edges(&nodes_to_remove_keeping_edges);
self.simplify();
!nodes_to_remove_keeping_edges.is_empty()
}
fn simplify(&mut self) {
@ -223,80 +228,3 @@ impl QueryGraph {
}
}
}
impl Debug for QueryNode {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
match self {
QueryNode::Term(term @ LocatedQueryTerm { value, positions: _ }) => match value {
QueryTerm::Word {
derivations:
WordDerivations { original, zero_typo, one_typo, two_typos, use_prefix_db },
} => {
if term.is_empty() {
write!(f, "\"{original} (∅)\"")
} else {
let derivations = std::iter::once(original.clone())
.chain(zero_typo.iter().map(|s| format!("T0 .. {s}")))
.chain(one_typo.iter().map(|s| format!("T1 .. {s}")))
.chain(two_typos.iter().map(|s| format!("T2 .. {s}")))
.collect::<Vec<String>>()
.join(" | ");
write!(f, "\"{derivations}")?;
if *use_prefix_db {
write!(f, " | +prefix_db")?;
}
write!(f, " | pos:{}..={}", term.positions.start(), term.positions.end())?;
write!(f, "\"")?;
/*
"beautiful" [label = "<f0> beautiful | beauiful | beautifol"]
*/
Ok(())
}
}
QueryTerm::Phrase(ws) => {
let joined =
ws.iter().filter_map(|x| x.clone()).collect::<Vec<String>>().join(" ");
let in_quotes = format!("\"{joined}\"");
let escaped = in_quotes.escape_default().collect::<String>();
write!(f, "\"{escaped}\"")
}
},
QueryNode::Start => write!(f, "\"START\""),
QueryNode::End => write!(f, "\"END\""),
QueryNode::Deleted => write!(f, "\"_deleted_\""),
}
}
}
impl QueryGraph {
pub fn graphviz(&self) -> String {
let mut desc = String::new();
desc.push_str(
r#"
digraph G {
rankdir = LR;
node [shape = "record"]
"#,
);
for node in 0..self.nodes.len() {
if matches!(self.nodes[node], QueryNode::Deleted) {
continue;
}
desc.push_str(&format!("{node} [label = {:?}]", &self.nodes[node],));
if node == self.root_node as usize {
desc.push_str("[color = blue]");
} else if node == self.end_node as usize {
desc.push_str("[color = red]");
}
desc.push_str(";\n");
for edge in self.edges[node].successors.iter() {
desc.push_str(&format!("{node} -> {edge};\n"));
}
}
desc.push('}');
desc
}
}

View File

@ -10,14 +10,28 @@ use fst::automaton::Str;
use fst::{Automaton, IntoStreamer, Streamer};
use heed::types::DecodeIgnore;
use heed::RoTxn;
use itertools::Itertools;
use crate::search::fst_utils::{Complement, Intersection, StartsWith, Union};
use crate::search::{build_dfa, get_first};
use crate::{Index, Result};
use crate::{CboRoaringBitmapLenCodec, Index, Result};
#[derive(Debug, Default, Clone)]
pub struct Phrase {
pub words: Vec<Option<String>>,
}
impl Phrase {
pub fn description(&self) -> String {
self.words.iter().flatten().join(" ")
}
}
#[derive(Debug, Clone)]
pub struct WordDerivations {
pub original: String,
// TODO: pub prefix_of: Vec<String>,
pub synonyms: Vec<Phrase>,
pub split_words: Option<(String, String)>,
pub zero_typo: Vec<String>,
pub one_typo: Vec<String>,
pub two_typos: Vec<String>,
@ -114,19 +128,63 @@ pub fn word_derivations(
}
}
}
let split_words = split_best_frequency(index, txn, word)?;
Ok(WordDerivations { original: word.to_owned(), zero_typo, one_typo, two_typos, use_prefix_db })
let synonyms = index.synonyms(txn)?;
let synonyms = synonyms
.get(&vec![word.to_owned()])
.cloned()
.unwrap_or_default()
.into_iter()
.map(|words| Phrase { words: words.into_iter().map(Some).collect() })
.collect();
Ok(WordDerivations {
original: word.to_owned(),
synonyms,
split_words,
zero_typo,
one_typo,
two_typos,
use_prefix_db,
})
}
fn split_best_frequency(
index: &Index,
txn: &RoTxn,
original: &str,
) -> Result<Option<(String, String)>> {
let chars = original.char_indices().skip(1);
let mut best = None;
for (i, _) in chars {
let (left, right) = original.split_at(i);
let key = (1, left, right);
let frequency = index
.word_pair_proximity_docids
.remap_data_type::<CboRoaringBitmapLenCodec>()
.get(txn, &key)?
.unwrap_or(0);
if frequency != 0 && best.map_or(true, |(old, _, _)| frequency > old) {
best = Some((frequency, left, right));
}
}
Ok(best.map(|(_, left, right)| (left.to_owned(), right.to_owned())))
}
#[derive(Debug, Clone)]
pub enum QueryTerm {
Phrase(Vec<Option<String>>),
Phrase { phrase: Phrase },
Word { derivations: WordDerivations },
}
impl QueryTerm {
pub fn original_single_word(&self) -> Option<&str> {
match self {
QueryTerm::Phrase(_) => None,
QueryTerm::Phrase { phrase: _ } => None,
QueryTerm::Word { derivations } => {
if derivations.is_empty() {
None
@ -140,14 +198,14 @@ impl QueryTerm {
#[derive(Debug, Clone)]
pub struct LocatedQueryTerm {
pub value: QueryTerm, // value should be able to contain the word derivations as well
pub value: QueryTerm,
pub positions: RangeInclusive<i8>,
}
impl LocatedQueryTerm {
pub fn is_empty(&self) -> bool {
match &self.value {
QueryTerm::Phrase(_) => false,
QueryTerm::Phrase { phrase: _ } => false,
QueryTerm::Word { derivations, .. } => derivations.is_empty(),
}
}
@ -156,6 +214,7 @@ impl LocatedQueryTerm {
pub fn from_query(
query: NormalizedTokenIter<Vec<u8>>,
words_limit: Option<usize>,
// TODO:` use index + txn + ? instead of closure
derivations: impl Fn(&str, bool) -> Result<WordDerivations>,
) -> Result<Vec<LocatedQueryTerm>> {
let mut primitive_query = Vec::new();
@ -232,7 +291,9 @@ impl LocatedQueryTerm {
&& (quote_count > 0 || separator_kind == SeparatorKind::Hard)
{
let located_query_term = LocatedQueryTerm {
value: QueryTerm::Phrase(mem::take(&mut phrase)),
value: QueryTerm::Phrase {
phrase: Phrase { words: mem::take(&mut phrase) },
},
positions: phrase_start..=phrase_end,
};
primitive_query.push(located_query_term);
@ -245,7 +306,7 @@ impl LocatedQueryTerm {
// If a quote is never closed, we consider all of the end of the query as a phrase.
if !phrase.is_empty() {
let located_query_term = LocatedQueryTerm {
value: QueryTerm::Phrase(mem::take(&mut phrase)),
value: QueryTerm::Phrase { phrase: Phrase { words: mem::take(&mut phrase) } },
positions: phrase_start..=phrase_end,
};
primitive_query.push(located_query_term);

View File

@ -5,9 +5,10 @@ use heed::{BytesDecode, RoTxn};
use roaring::{MultiOps, RoaringBitmap};
use super::db_cache::DatabaseCache;
use super::query_term::{QueryTerm, WordDerivations};
use super::QueryGraph;
use crate::{Index, Result, RoaringBitmapCodec};
use super::query_term::{Phrase, QueryTerm, WordDerivations};
use super::{QueryGraph, QueryNode};
use crate::{CboRoaringBitmapCodec, Index, Result, RoaringBitmapCodec};
// TODO: manual performance metrics: access to DB, bitmap deserializations/operations, etc.
#[derive(Default)]
@ -27,14 +28,19 @@ impl NodeDocIdsCache {
return Ok(&self.cache[&node_idx]);
};
let docids = match term {
QueryTerm::Phrase(_) => {
todo!("resolve phrase")
}
QueryTerm::Phrase { phrase } => resolve_phrase(index, txn, db_cache, phrase)?,
QueryTerm::Word {
derivations:
WordDerivations { original, zero_typo, one_typo, two_typos, use_prefix_db },
WordDerivations {
original,
zero_typo,
one_typo,
two_typos,
use_prefix_db,
synonyms,
split_words,
},
} => {
let derivations_docids = {
let mut or_docids = vec![];
for word in zero_typo.iter().chain(one_typo.iter()).chain(two_typos.iter()) {
if let Some(word_docids) = db_cache.get_word_docids(index, txn, word)? {
@ -48,12 +54,23 @@ impl NodeDocIdsCache {
or_docids.push(prefix_docids);
}
}
or_docids
};
let derivations_iter = derivations_docids
let mut docids = or_docids
.into_iter()
.map(|slice| RoaringBitmapCodec::bytes_decode(slice).unwrap());
MultiOps::union(derivations_iter)
.map(|slice| RoaringBitmapCodec::bytes_decode(slice).unwrap())
.collect::<Vec<_>>();
for synonym in synonyms {
// TODO: cache resolve_phrase?
docids.push(resolve_phrase(index, txn, db_cache, synonym)?);
}
if let Some((left, right)) = split_words {
if let Some(split_word_docids) =
db_cache.get_word_pair_proximity_docids(index, txn, left, right, 1)?
{
docids.push(CboRoaringBitmapCodec::deserialize_from(split_word_docids)?);
}
}
MultiOps::union(docids)
}
};
let _ = self.cache.insert(node_idx, docids);
@ -90,19 +107,19 @@ pub fn resolve_query_graph<'transaction>(
let predecessors_docids = MultiOps::union(predecessors_iter);
let n = &q.nodes[node as usize];
// println!("resolving {node} {n:?}, predecessors: {predecessors:?}, their docids: {predecessors_docids:?}");
let node_docids = match n {
super::QueryNode::Term(located_term) => {
QueryNode::Term(located_term) => {
let term = &located_term.value;
let derivations_docids =
node_docids_cache.get_docids(index, txn, db_cache, term, node)?;
predecessors_docids & derivations_docids
}
super::QueryNode::Deleted => {
QueryNode::Deleted => {
panic!()
}
super::QueryNode::Start => universe.clone(),
super::QueryNode::End => {
QueryNode::Start => universe.clone(),
QueryNode::End => {
return Ok(predecessors_docids);
}
};
@ -125,3 +142,80 @@ pub fn resolve_query_graph<'transaction>(
panic!()
}
pub fn resolve_phrase<'transaction>(
index: &Index,
txn: &'transaction RoTxn,
db_cache: &mut DatabaseCache<'transaction>,
phrase: &Phrase,
) -> Result<RoaringBitmap> {
let Phrase { words } = phrase;
let mut candidates = RoaringBitmap::new();
let mut first_iter = true;
let winsize = words.len().min(3);
if words.is_empty() {
return Ok(candidates);
}
for win in words.windows(winsize) {
// Get all the documents with the matching distance for each word pairs.
let mut bitmaps = Vec::with_capacity(winsize.pow(2));
for (offset, s1) in win
.iter()
.enumerate()
.filter_map(|(index, word)| word.as_ref().map(|word| (index, word)))
{
for (dist, s2) in win
.iter()
.skip(offset + 1)
.enumerate()
.filter_map(|(index, word)| word.as_ref().map(|word| (index, word)))
{
if dist == 0 {
match db_cache.get_word_pair_proximity_docids(index, txn, s1, s2, 1)? {
Some(m) => bitmaps.push(CboRoaringBitmapCodec::deserialize_from(m)?),
// If there are no documents for this pair, there will be no
// results for the phrase query.
None => return Ok(RoaringBitmap::new()),
}
} else {
let mut bitmap = RoaringBitmap::new();
for dist in 0..=dist {
if let Some(m) = db_cache.get_word_pair_proximity_docids(
index,
txn,
s1,
s2,
dist as u8 + 1,
)? {
bitmap |= CboRoaringBitmapCodec::deserialize_from(m)?;
}
}
if bitmap.is_empty() {
return Ok(bitmap);
} else {
bitmaps.push(bitmap);
}
}
}
}
// We sort the bitmaps so that we perform the small intersections first, which is faster.
bitmaps.sort_unstable_by_key(|a| a.len());
for bitmap in bitmaps {
if first_iter {
candidates = bitmap;
first_iter = false;
} else {
candidates &= bitmap;
}
// There will be no match, return early
if candidates.is_empty() {
break;
}
}
}
Ok(candidates)
}

View File

@ -99,14 +99,17 @@ impl<'transaction> RankingRule<'transaction, QueryGraph> for Words {
)?;
let child_query_graph = query_graph.clone();
// TODO: Check whether a position exists in the graph before removing it and
// returning the next bucket.
// while graph.does_not_contain(positions_to_remove.last()) { positions_to_remove.pop() }
loop {
if self.positions_to_remove.is_empty() {
self.exhausted = true;
break;
} else {
let position_to_remove = self.positions_to_remove.pop().unwrap();
query_graph.remove_words_at_position(position_to_remove);
let did_delete_any_node = query_graph.remove_words_at_position(position_to_remove);
if did_delete_any_node {
break;
}
}
}
Ok(Some(RankingRuleOutput { query: child_query_graph, candidates: this_bucket }))