mirror of
https://github.com/meilisearch/MeiliSearch
synced 2025-05-25 09:03:59 +02:00
921 lines
36 KiB
Rust
921 lines
36 KiB
Rust
/*!
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## What is WordPrefixPairProximityDocids?
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The word-prefix-pair-proximity-docids database is a database whose keys are of
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the form `(proximity, word, prefix)` and the values are roaring bitmaps of
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the documents which contain `word` followed by another word starting with
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`prefix` at a distance of `proximity`.
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The prefixes present in this database are only those that correspond to many
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different words in the documents.
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## How is it created/updated? (simplified version)
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To compute it, we have access to (mainly) two inputs:
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* a list of sorted prefixes, such as:
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```text
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c
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ca
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cat
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d
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do
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dog
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```
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Note that only prefixes which correspond to more than a certain number of
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different words from the database are included in this list.
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* a sorted list of proximities and word pairs (the proximity is the distance between the two words),
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associated with a roaring bitmap, such as:
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```text
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1 good doggo -> docids1: [8]
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1 good door -> docids2: [7, 19, 20]
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1 good ghost -> docids3: [1]
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2 good dog -> docids4: [2, 5, 6]
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2 horror cathedral -> docids5: [1, 2]
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```
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I illustrate a simplified version of the algorithm to create the word-prefix
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pair-proximity database below:
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1. **Outer loop:** First, we iterate over each proximity and word pair:
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```text
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proximity: 1
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word1 : good
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word2 : doggo
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```
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2. **Inner loop:** Then, we iterate over all the prefixes of `word2` that are
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in the list of sorted prefixes. And we insert the key `prefix`
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and the value (`docids`) to a sorted map which we call the “batch”. For example,
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at the end of the first inner loop, we may have:
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```text
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Outer loop 1:
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------------------------------
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proximity: 1
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word1 : good
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word2 : doggo
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docids : docids1
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prefixes: [d, do, dog]
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batch: [
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d, -> [docids1]
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do -> [docids1]
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dog -> [docids1]
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]
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```
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3. For illustration purpose, let's run through a second iteration of the outer loop:
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```text
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Outer loop 2:
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------------------------------
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proximity: 1
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word1 : good
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word2 : door
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docids : docids2
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prefixes: [d, do, doo]
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batch: [
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d -> [docids1, docids2]
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do -> [docids1, docids2]
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dog -> [docids1]
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doo -> [docids2]
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]
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```
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Notice that there were some conflicts which were resolved by merging the
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conflicting values together. Also, an additional prefix was added at the
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end of the batch.
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4. On the third iteration of the outer loop, we have:
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```text
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Outer loop 4:
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------------------------------
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proximity: 1
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word1 : good
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word2 : ghost
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```
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Because `word2` begins with a different letter than the previous `word2`,
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we know that all the prefixes of `word2` are greater than the prefixes of the previous word2
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Therefore, we know that we can insert every element from the batch into the
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database before proceeding any further. This operation is called
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“flushing the batch”. Flushing the batch should also be done whenever:
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* `proximity` is different than the previous `proximity`.
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* `word1` is different than the previous `word1`.
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* `word2` starts with a different letter than the previous word2
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6. **Flushing the batch:** to flush the batch, we iterate over its elements:
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```text
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Flushing Batch loop 1:
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------------------------------
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proximity : 1
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word1 : good
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prefix : d
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docids : [docids2, docids3]
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```
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We then merge the array of `docids` (of type `Vec<Vec<u8>>`) using
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`merge_cbo_roaring_bitmap` in order to get a single byte vector representing a
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roaring bitmap of all the document ids where `word1` is followed by `prefix`
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at a distance of `proximity`.
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Once we have done that, we insert `(proximity, word1, prefix) -> merged_docids`
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into the database.
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7. That's it! ... except...
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## How is it created/updated (continued)
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I lied a little bit about the input data. In reality, we get two sets of the
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inputs described above, which come from different places:
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* For the list of sorted prefixes, we have:
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1. `new_prefixes`, which are all the prefixes that were not present in the
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database before the insertion of the new documents
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2. `common_prefixes` which are the prefixes that are present both in the
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database and in the newly added documents
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* For the list of word pairs and proximities, we have:
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1. `new_word_pairs`, which is the list of word pairs and their proximities
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present in the newly added documents
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2. `word_pairs_db`, which is the list of word pairs from the database.
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This list includes all elements in `new_word_pairs` since `new_word_pairs`
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was added to the database prior to calling the `WordPrefixPairProximityDocIds::execute`
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function.
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To update the prefix database correctly, we call the algorithm described earlier first
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on (`common_prefixes`, `new_word_pairs`) and then on (`new_prefixes`, `word_pairs_db`).
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Thus:
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1. For all the word pairs that were already present in the DB, we insert them
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again with the `new_prefixes`. Calling the algorithm on them with the
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`common_prefixes` would not result in any new data.
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2. For all the new word pairs, we insert them twice: first with the `common_prefixes`,
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and then, because they are part of `word_pairs_db`, with the `new_prefixes`.
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Note, also, that since we read data from the database when iterating over
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`word_pairs_db`, we cannot insert the computed word-prefix-pair-proximity-
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docids from the batch directly into the database (we would have a concurrent
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reader and writer). Therefore, when calling the algorithm on
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`(new_prefixes, word_pairs_db)`, we insert the computed
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`((proximity, word, prefix), docids)` elements in an intermediary grenad
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Writer instead of the DB. At the end of the outer loop, we finally read from
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the grenad and insert its elements in the database.
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*/
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use std::borrow::Cow;
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use std::collections::HashSet;
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use std::io::BufReader;
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use grenad::CompressionType;
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use heed::types::ByteSlice;
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use heed::BytesDecode;
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use log::debug;
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use crate::update::index_documents::{
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create_writer, merge_cbo_roaring_bitmaps, CursorClonableMmap,
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};
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use crate::{CboRoaringBitmapCodec, Index, Result, UncheckedStrStrU8Codec};
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pub struct WordPrefixPairProximityDocids<'t, 'u, 'i> {
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wtxn: &'t mut heed::RwTxn<'i, 'u>,
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index: &'i Index,
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pub(crate) chunk_compression_type: CompressionType,
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pub(crate) chunk_compression_level: Option<u32>,
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pub(crate) max_nb_chunks: Option<usize>,
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pub(crate) max_memory: Option<usize>,
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max_proximity: u8,
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max_prefix_length: usize,
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}
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impl<'t, 'u, 'i> WordPrefixPairProximityDocids<'t, 'u, 'i> {
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pub fn new(
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wtxn: &'t mut heed::RwTxn<'i, 'u>,
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index: &'i Index,
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) -> WordPrefixPairProximityDocids<'t, 'u, 'i> {
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WordPrefixPairProximityDocids {
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wtxn,
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index,
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chunk_compression_type: CompressionType::None,
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chunk_compression_level: None,
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max_nb_chunks: None,
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max_memory: None,
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max_proximity: 4,
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max_prefix_length: 2,
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}
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}
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/// Set the maximum proximity required to make a prefix be part of the words prefixes
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/// database. If two words are too far from the threshold the associated documents will
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/// not be part of the prefix database.
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///
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/// Default value is 4. This value must be lower or equal than 7 and will be clamped
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/// to this bound otherwise.
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pub fn max_proximity(&mut self, value: u8) -> &mut Self {
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self.max_proximity = value.max(7);
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self
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}
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/// Set the maximum length the prefix of a word pair is allowed to have to be part of the words
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/// prefixes database. If the prefix length is higher than the threshold, the associated documents
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/// will not be part of the prefix database.
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///
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/// Default value is 2.
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pub fn max_prefix_length(&mut self, value: usize) -> &mut Self {
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self.max_prefix_length = value;
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self
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}
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#[logging_timer::time("WordPrefixPairProximityDocids::{}")]
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pub fn execute<'a>(
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mut self,
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new_word_pair_proximity_docids: grenad::Reader<CursorClonableMmap>,
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new_prefix_fst_words: &'a [String],
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common_prefix_fst_words: &[&'a [String]],
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del_prefix_fst_words: &HashSet<Vec<u8>>,
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) -> Result<()> {
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debug!("Computing and writing the word prefix pair proximity docids into LMDB on disk...");
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// Make a prefix trie from the common prefixes that are shorter than self.max_prefix_length
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let prefixes = PrefixTrieNode::from_sorted_prefixes(
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common_prefix_fst_words
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.into_iter()
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.map(|s| s.into_iter())
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.flatten()
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.map(|s| s.as_str())
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.filter(|s| s.len() <= self.max_prefix_length),
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);
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// If the prefix trie is not empty, then we can iterate over all new
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// word pairs to look for new (word1, common_prefix, proximity) elements
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// to insert in the DB
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if !prefixes.is_empty() {
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let mut cursor = new_word_pair_proximity_docids.into_cursor()?;
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// This is the core of the algorithm
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execute_on_word_pairs_and_prefixes(
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// the first two arguments tell how to iterate over the new word pairs
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&mut cursor,
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|cursor| {
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if let Some((key, value)) = cursor.move_on_next()? {
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let (word1, word2, proximity) = UncheckedStrStrU8Codec::bytes_decode(key)
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.ok_or(heed::Error::Decoding)?;
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Ok(Some(((word1, word2, proximity), value)))
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} else {
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Ok(None)
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}
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},
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&prefixes,
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self.max_proximity,
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// and this argument tells what to do with each new key (word1, prefix, proximity) and value (roaring bitmap)
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|key, value| {
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insert_into_database(
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&mut self.wtxn,
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*self.index.word_prefix_pair_proximity_docids.as_polymorph(),
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key,
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value,
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)
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},
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)?;
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}
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// Now we do the same thing with the new prefixes and all word pairs in the DB
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let prefixes = PrefixTrieNode::from_sorted_prefixes(
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new_prefix_fst_words
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.into_iter()
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.map(|s| s.as_str())
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.filter(|s| s.len() <= self.max_prefix_length),
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);
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if !prefixes.is_empty() {
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let mut db_iter = self
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.index
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.word_pair_proximity_docids
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.remap_key_type::<UncheckedStrStrU8Codec>()
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.remap_data_type::<ByteSlice>()
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.iter(self.wtxn)?;
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// Since we read the DB, we can't write to it directly, so we add each new (word1, prefix, proximity)
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// element in an intermediary grenad
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let mut writer = create_writer(
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self.chunk_compression_type,
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self.chunk_compression_level,
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tempfile::tempfile()?,
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);
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execute_on_word_pairs_and_prefixes(
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&mut db_iter,
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|db_iter| db_iter.next().transpose().map_err(|e| e.into()),
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&prefixes,
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self.max_proximity,
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|key, value| writer.insert(key, value).map_err(|e| e.into()),
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)?;
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drop(db_iter);
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// and then we write the grenad into the DB
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// Since the grenad contains only new prefixes, we know in advance that none
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// of its elements already exist in the DB, thus there is no need to specify
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// how to merge conflicting elements
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write_into_lmdb_database_without_merging(
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self.wtxn,
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*self.index.word_prefix_pair_proximity_docids.as_polymorph(),
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writer,
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)?;
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}
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// All of the word prefix pairs in the database that have a w2
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// that is contained in the `suppr_pw` set must be removed as well.
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if !del_prefix_fst_words.is_empty() {
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let mut iter = self
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.index
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.word_prefix_pair_proximity_docids
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.remap_data_type::<ByteSlice>()
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.iter_mut(self.wtxn)?;
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while let Some(((_, w2, _), _)) = iter.next().transpose()? {
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if del_prefix_fst_words.contains(w2.as_bytes()) {
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// Delete this entry as the w2 prefix is no more in the words prefix fst.
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unsafe { iter.del_current()? };
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}
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}
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}
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Ok(())
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}
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}
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/// This is the core of the algorithm to initialise the Word Prefix Pair Proximity Docids database.
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///
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/// Its main arguments are:
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/// 1. a sorted iterator over ((word1, word2, proximity), docids) elements
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/// 2. a prefix trie
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/// 3. a closure to describe how to handle the new computed (word1, prefix, proximity) elements
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///
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/// For more information about what this function does, read the module documentation.
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fn execute_on_word_pairs_and_prefixes<I>(
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iter: &mut I,
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mut next_word_pair_proximity: impl for<'a> FnMut(
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&'a mut I,
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) -> Result<
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Option<((&'a [u8], &'a [u8], u8), &'a [u8])>,
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>,
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prefixes: &PrefixTrieNode,
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max_proximity: u8,
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mut insert: impl for<'a> FnMut(&'a [u8], &'a [u8]) -> Result<()>,
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) -> Result<()> {
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let mut batch = PrefixAndProximityBatch::default();
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let mut prev_word2_start = 0;
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// Optimisation: the index at the root of the prefix trie where to search for
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let mut prefix_search_start = PrefixTrieNodeSearchStart(0);
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// Optimisation: true if there are no potential prefixes for the current word2 based on its first letter
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let mut empty_prefixes = false;
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let mut prefix_buffer = Vec::with_capacity(8);
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let mut merge_buffer = Vec::with_capacity(65_536);
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while let Some(((word1, word2, proximity), data)) = next_word_pair_proximity(iter)? {
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// skip this iteration if the proximity is over the threshold
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if proximity > max_proximity {
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break;
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};
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let word2_start_different_than_prev = word2[0] != prev_word2_start;
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// if there were no potential prefixes for the previous word2 based on its first letter,
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// and if the current word2 starts with the same letter, then there is also no potential
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// prefixes for the current word2, and we can skip to the next iteration
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if empty_prefixes && !word2_start_different_than_prev {
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continue;
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}
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// if the proximity is different to the previous one, OR
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// if word1 is different than the previous word1, OR
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// if the start of word2 is different than the previous start of word2,
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// THEN we'll need to flush the batch
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let prox_different_than_prev = proximity != batch.proximity;
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let word1_different_than_prev = word1 != batch.word1;
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if prox_different_than_prev || word1_different_than_prev || word2_start_different_than_prev
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{
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batch.flush(&mut merge_buffer, &mut insert)?;
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// don't forget to reset the value of batch.word1 and prev_word2_start
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if word1_different_than_prev {
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prefix_search_start.0 = 0;
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batch.word1.clear();
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batch.word1.extend_from_slice(word1);
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batch.proximity = proximity;
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}
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if word2_start_different_than_prev {
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// word2_start_different_than_prev == true
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prev_word2_start = word2[0];
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}
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// Optimisation: find the search start in the prefix trie to iterate over the prefixes of word2
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empty_prefixes = !prefixes.set_search_start(word2, &mut prefix_search_start);
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}
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if !empty_prefixes {
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// All conditions are satisfied, we can now insert each new prefix of word2 into the batch
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prefix_buffer.clear();
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prefixes.for_each_prefix_of(
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word2,
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&mut prefix_buffer,
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&prefix_search_start,
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|prefix_buffer| {
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batch.insert(&prefix_buffer, data.to_vec());
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},
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);
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}
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}
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batch.flush(&mut merge_buffer, &mut insert)?;
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Ok(())
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}
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/**
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A map structure whose keys are prefixes and whose values are vectors of bitstrings (serialized roaring bitmaps).
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The keys are sorted and conflicts are resolved by merging the vectors of bitstrings together.
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It is used to ensure that all ((proximity, word1, prefix), docids) are inserted into the database in sorted order and efficiently.
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The batch is flushed as often as possible, when we are sure that every (proximity, word1, prefix) key derived from its content
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can be inserted into the database in sorted order. When it is flushed, it calls a user-provided closure with the following arguments:
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- key : (proximity, word1, prefix) as bytes
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- value : merged roaring bitmaps from all values associated with prefix in the batch, serialised to bytes
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*/
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#[derive(Default)]
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struct PrefixAndProximityBatch {
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proximity: u8,
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word1: Vec<u8>,
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batch: Vec<(Vec<u8>, Vec<Cow<'static, [u8]>>)>,
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}
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impl PrefixAndProximityBatch {
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/// Insert the new key and value into the batch
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///
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/// The key must either exist in the batch or be greater than all existing keys
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fn insert(&mut self, new_key: &[u8], new_value: Vec<u8>) {
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match self.batch.iter_mut().find(|el| el.0 == new_key) {
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Some((_prefix, docids)) => docids.push(Cow::Owned(new_value)),
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None => self.batch.push((new_key.to_vec(), vec![Cow::Owned(new_value)])),
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}
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}
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/// Empties the batch, calling `insert` on each element.
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///
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/// The key given to `insert` is `(proximity, word1, prefix)` and the value is the associated merged roaring bitmap.
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fn flush(
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&mut self,
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merge_buffer: &mut Vec<u8>,
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insert: &mut impl for<'buffer> FnMut(&'buffer [u8], &'buffer [u8]) -> Result<()>,
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) -> Result<()> {
|
|
let PrefixAndProximityBatch { proximity, word1, batch } = self;
|
|
if batch.is_empty() {
|
|
return Ok(());
|
|
}
|
|
merge_buffer.clear();
|
|
|
|
let mut buffer = Vec::with_capacity(word1.len() + 1 + 6);
|
|
buffer.push(*proximity);
|
|
buffer.extend_from_slice(word1);
|
|
buffer.push(0);
|
|
|
|
for (key, mergeable_data) in batch.drain(..) {
|
|
buffer.truncate(1 + word1.len() + 1);
|
|
buffer.extend_from_slice(key.as_slice());
|
|
|
|
let data = if mergeable_data.len() > 1 {
|
|
CboRoaringBitmapCodec::merge_into(&mergeable_data, merge_buffer)?;
|
|
merge_buffer.as_slice()
|
|
} else {
|
|
&mergeable_data[0]
|
|
};
|
|
insert(buffer.as_slice(), data)?;
|
|
merge_buffer.clear();
|
|
}
|
|
|
|
Ok(())
|
|
}
|
|
}
|
|
|
|
// This is adapted from `sorter_into_lmdb_database`
|
|
fn insert_into_database(
|
|
wtxn: &mut heed::RwTxn,
|
|
database: heed::PolyDatabase,
|
|
new_key: &[u8],
|
|
new_value: &[u8],
|
|
) -> Result<()> {
|
|
let mut iter = database.prefix_iter_mut::<_, ByteSlice, ByteSlice>(wtxn, new_key)?;
|
|
match iter.next().transpose()? {
|
|
Some((key, old_val)) if new_key == key => {
|
|
let val =
|
|
merge_cbo_roaring_bitmaps(key, &[Cow::Borrowed(old_val), Cow::Borrowed(new_value)])
|
|
.map_err(|_| {
|
|
// TODO just wrap this error?
|
|
crate::error::InternalError::IndexingMergingKeys {
|
|
process: "get-put-merge",
|
|
}
|
|
})?;
|
|
// safety: we use the new_key, not the one from the database iterator, to avoid undefined behaviour
|
|
unsafe { iter.put_current(new_key, &val)? };
|
|
}
|
|
_ => {
|
|
drop(iter);
|
|
database.put::<_, ByteSlice, ByteSlice>(wtxn, new_key, new_value)?;
|
|
}
|
|
}
|
|
Ok(())
|
|
}
|
|
|
|
// This is adapted from `sorter_into_lmdb_database` and `write_into_lmdb_database`,
|
|
// but it uses `append` if the database is empty, and it assumes that the values in the
|
|
// writer don't conflict with values in the database.
|
|
pub fn write_into_lmdb_database_without_merging(
|
|
wtxn: &mut heed::RwTxn,
|
|
database: heed::PolyDatabase,
|
|
writer: grenad::Writer<std::fs::File>,
|
|
) -> Result<()> {
|
|
let file = writer.into_inner()?;
|
|
let reader = grenad::Reader::new(BufReader::new(file))?;
|
|
if database.is_empty(wtxn)? {
|
|
let mut out_iter = database.iter_mut::<_, ByteSlice, ByteSlice>(wtxn)?;
|
|
let mut cursor = reader.into_cursor()?;
|
|
while let Some((k, v)) = cursor.move_on_next()? {
|
|
// safety: the key comes from the grenad reader, not the database
|
|
unsafe { out_iter.append(k, v)? };
|
|
}
|
|
} else {
|
|
let mut cursor = reader.into_cursor()?;
|
|
while let Some((k, v)) = cursor.move_on_next()? {
|
|
database.put::<_, ByteSlice, ByteSlice>(wtxn, k, v)?;
|
|
}
|
|
}
|
|
Ok(())
|
|
}
|
|
|
|
/** A prefix trie. Used to iterate quickly over the prefixes of a word that are
|
|
within a set.
|
|
|
|
## Structure
|
|
The trie is made of nodes composed of:
|
|
1. a byte character (e.g. 'a')
|
|
2. whether the node is an end node or not
|
|
3. a list of children nodes, sorted by their byte character
|
|
|
|
For example, the trie that stores the strings `[ac, ae, ar, ch, cei, cel, ch, r, rel, ri]`
|
|
is drawn below. Nodes with a double border are "end nodes".
|
|
|
|
┌──────────────────────┐ ┌──────────────────────┐ ╔══════════════════════╗
|
|
│ a │ │ c │ ║ r ║
|
|
└──────────────────────┘ └──────────────────────┘ ╚══════════════════════╝
|
|
╔══════╗╔══════╗╔══════╗ ┌─────────┐ ╔═════════╗ ┌─────────┐ ╔══════════╗
|
|
║ c ║║ e ║║ r ║ │ e │ ║ h ║ │ e │ ║ i ║
|
|
╚══════╝╚══════╝╚══════╝ └─────────┘ ╚═════════╝ └─────────┘ ╚══════════╝
|
|
╔═══╗ ╔═══╗ ╔═══╗
|
|
║ i ║ ║ l ║ ║ l ║
|
|
╚═══╝ ╚═══╝ ╚═══╝
|
|
*/
|
|
#[derive(Default, Debug)]
|
|
struct PrefixTrieNode {
|
|
children: Vec<(PrefixTrieNode, u8)>,
|
|
is_end_node: bool,
|
|
}
|
|
|
|
#[derive(Debug)]
|
|
struct PrefixTrieNodeSearchStart(usize);
|
|
|
|
impl PrefixTrieNode {
|
|
fn is_empty(&self) -> bool {
|
|
self.children.is_empty()
|
|
}
|
|
|
|
/// Returns false if the trie does not contain a prefix of the given word.
|
|
/// Returns true if the trie *may* contain a prefix of the given word.
|
|
///
|
|
/// Moves the search start to the first node equal to the first letter of the word,
|
|
/// or to 0 otherwise.
|
|
fn set_search_start(&self, word: &[u8], search_start: &mut PrefixTrieNodeSearchStart) -> bool {
|
|
let byte = word[0];
|
|
if self.children[search_start.0].1 == byte {
|
|
return true;
|
|
} else {
|
|
match self.children[search_start.0..].binary_search_by_key(&byte, |x| x.1) {
|
|
Ok(position) => {
|
|
search_start.0 += position;
|
|
true
|
|
}
|
|
Err(_) => {
|
|
search_start.0 = 0;
|
|
false
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
fn from_sorted_prefixes<'a>(prefixes: impl Iterator<Item = &'a str>) -> Self {
|
|
let mut node = PrefixTrieNode::default();
|
|
for prefix in prefixes {
|
|
node.insert_sorted_prefix(prefix.as_bytes().into_iter());
|
|
}
|
|
node
|
|
}
|
|
fn insert_sorted_prefix(&mut self, mut prefix: std::slice::Iter<u8>) {
|
|
if let Some(&c) = prefix.next() {
|
|
if let Some((node, byte)) = self.children.last_mut() {
|
|
if *byte == c {
|
|
node.insert_sorted_prefix(prefix);
|
|
return;
|
|
}
|
|
}
|
|
let mut new_node = PrefixTrieNode::default();
|
|
new_node.insert_sorted_prefix(prefix);
|
|
self.children.push((new_node, c));
|
|
} else {
|
|
self.is_end_node = true;
|
|
}
|
|
}
|
|
|
|
/// Call the given closure on each prefix of the word contained in the prefix trie.
|
|
///
|
|
/// The search starts from the given `search_start`.
|
|
fn for_each_prefix_of(
|
|
&self,
|
|
word: &[u8],
|
|
buffer: &mut Vec<u8>,
|
|
search_start: &PrefixTrieNodeSearchStart,
|
|
mut do_fn: impl FnMut(&mut Vec<u8>),
|
|
) {
|
|
let first_byte = word[0];
|
|
let mut cur_node = self;
|
|
buffer.push(first_byte);
|
|
if let Some((child_node, c)) =
|
|
cur_node.children[search_start.0..].iter().find(|(_, c)| *c >= first_byte)
|
|
{
|
|
if *c == first_byte {
|
|
cur_node = child_node;
|
|
if cur_node.is_end_node {
|
|
do_fn(buffer);
|
|
}
|
|
for &byte in &word[1..] {
|
|
buffer.push(byte);
|
|
if let Some((child_node, c)) =
|
|
cur_node.children.iter().find(|(_, c)| *c >= byte)
|
|
{
|
|
if *c == byte {
|
|
cur_node = child_node;
|
|
if cur_node.is_end_node {
|
|
do_fn(buffer);
|
|
}
|
|
} else {
|
|
break;
|
|
}
|
|
} else {
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
#[cfg(test)]
|
|
mod tests {
|
|
use std::io::Cursor;
|
|
|
|
use roaring::RoaringBitmap;
|
|
|
|
use super::*;
|
|
use crate::documents::{DocumentsBatchBuilder, DocumentsBatchReader};
|
|
use crate::index::tests::TempIndex;
|
|
use crate::{db_snap, CboRoaringBitmapCodec, StrStrU8Codec};
|
|
|
|
fn documents_with_enough_different_words_for_prefixes(prefixes: &[&str]) -> Vec<crate::Object> {
|
|
let mut documents = Vec::new();
|
|
for prefix in prefixes {
|
|
for i in 0..50 {
|
|
documents.push(
|
|
serde_json::json!({
|
|
"text": format!("{prefix}{i:x}"),
|
|
})
|
|
.as_object()
|
|
.unwrap()
|
|
.clone(),
|
|
)
|
|
}
|
|
}
|
|
documents
|
|
}
|
|
|
|
#[test]
|
|
fn test_update() {
|
|
let mut index = TempIndex::new();
|
|
index.index_documents_config.words_prefix_threshold = Some(50);
|
|
index.index_documents_config.autogenerate_docids = true;
|
|
|
|
index
|
|
.update_settings(|settings| {
|
|
settings.set_searchable_fields(vec!["text".to_owned()]);
|
|
})
|
|
.unwrap();
|
|
|
|
let batch_reader_from_documents = |documents| {
|
|
let mut builder = DocumentsBatchBuilder::new(Vec::new());
|
|
for object in documents {
|
|
builder.append_json_object(&object).unwrap();
|
|
}
|
|
DocumentsBatchReader::from_reader(Cursor::new(builder.into_inner().unwrap())).unwrap()
|
|
};
|
|
|
|
let mut documents = documents_with_enough_different_words_for_prefixes(&["a", "be"]);
|
|
// now we add some documents where the text should populate the word_prefix_pair_proximity_docids database
|
|
documents.push(
|
|
serde_json::json!({
|
|
"text": "At an amazing and beautiful house"
|
|
})
|
|
.as_object()
|
|
.unwrap()
|
|
.clone(),
|
|
);
|
|
documents.push(
|
|
serde_json::json!({
|
|
"text": "The bell rings at 5 am"
|
|
})
|
|
.as_object()
|
|
.unwrap()
|
|
.clone(),
|
|
);
|
|
|
|
let documents = batch_reader_from_documents(documents);
|
|
index.add_documents(documents).unwrap();
|
|
|
|
db_snap!(index, word_prefix_pair_proximity_docids, "initial");
|
|
|
|
let mut documents = documents_with_enough_different_words_for_prefixes(&["am", "an"]);
|
|
documents.push(
|
|
serde_json::json!({
|
|
"text": "At an extraordinary house"
|
|
})
|
|
.as_object()
|
|
.unwrap()
|
|
.clone(),
|
|
);
|
|
let documents = batch_reader_from_documents(documents);
|
|
index.add_documents(documents).unwrap();
|
|
|
|
db_snap!(index, word_prefix_pair_proximity_docids, "update");
|
|
}
|
|
|
|
fn check_prefixes(
|
|
trie: &PrefixTrieNode,
|
|
search_start: &PrefixTrieNodeSearchStart,
|
|
word: &str,
|
|
expected_prefixes: &[&str],
|
|
) {
|
|
let mut actual_prefixes = vec![];
|
|
trie.for_each_prefix_of(word.as_bytes(), &mut Vec::new(), &search_start, |x| {
|
|
let s = String::from_utf8(x.to_owned()).unwrap();
|
|
actual_prefixes.push(s);
|
|
});
|
|
assert_eq!(actual_prefixes, expected_prefixes);
|
|
}
|
|
|
|
#[test]
|
|
fn test_trie() {
|
|
let trie = PrefixTrieNode::from_sorted_prefixes(IntoIterator::into_iter([
|
|
"1", "19", "2", "a", "ab", "ac", "ad", "al", "am", "an", "ap", "ar", "as", "at", "au",
|
|
"b", "ba", "bar", "be", "bi", "bl", "bla", "bo", "br", "bra", "bri", "bro", "bu", "c",
|
|
"ca", "car", "ce", "ch", "cha", "che", "chi", "ci", "cl", "cla", "co", "col", "com",
|
|
"comp", "con", "cons", "cont", "cor", "cou", "cr", "cu", "d", "da", "de", "dec", "des",
|
|
"di", "dis", "do", "dr", "du", "e", "el", "em", "en", "es", "ev", "ex", "exp", "f",
|
|
"fa", "fe", "fi", "fl", "fo", "for", "fr", "fra", "fre", "fu", "g", "ga", "ge", "gi",
|
|
"gl", "go", "gr", "gra", "gu", "h", "ha", "har", "he", "hea", "hi", "ho", "hu", "i",
|
|
"im", "imp", "in", "ind", "ins", "int", "inte", "j", "ja", "je", "jo", "ju", "k", "ka",
|
|
"ke", "ki", "ko", "l", "la", "le", "li", "lo", "lu", "m", "ma", "mal", "man", "mar",
|
|
"mat", "mc", "me", "mi", "min", "mis", "mo", "mon", "mor", "mu", "n", "na", "ne", "ni",
|
|
"no", "o", "or", "ou", "ov", "ove", "over", "p", "pa", "par", "pe", "per", "ph", "pi",
|
|
"pl", "po", "pr", "pre", "pro", "pu", "q", "qu", "r", "ra", "re", "rec", "rep", "res",
|
|
"ri", "ro", "ru", "s", "sa", "san", "sc", "sch", "se", "sh", "sha", "shi", "sho", "si",
|
|
"sk", "sl", "sn", "so", "sp", "st", "sta", "ste", "sto", "str", "su", "sup", "sw", "t",
|
|
"ta", "te", "th", "ti", "to", "tr", "tra", "tri", "tu", "u", "un", "v", "va", "ve",
|
|
"vi", "vo", "w", "wa", "we", "wh", "wi", "wo", "y", "yo", "z",
|
|
]));
|
|
|
|
let mut search_start = PrefixTrieNodeSearchStart(0);
|
|
|
|
let is_empty = !trie.set_search_start("affair".as_bytes(), &mut search_start);
|
|
assert!(!is_empty);
|
|
assert_eq!(search_start.0, 2);
|
|
|
|
check_prefixes(&trie, &search_start, "affair", &["a"]);
|
|
check_prefixes(&trie, &search_start, "shampoo", &["s", "sh", "sha"]);
|
|
|
|
let is_empty = !trie.set_search_start("unique".as_bytes(), &mut search_start);
|
|
assert!(!is_empty);
|
|
assert_eq!(trie.children[search_start.0].1, b'u');
|
|
|
|
check_prefixes(&trie, &search_start, "unique", &["u", "un"]);
|
|
|
|
// NOTE: this should fail, because the search start is already beyong 'a'
|
|
let is_empty = trie.set_search_start("abba".as_bytes(), &mut search_start);
|
|
assert!(!is_empty);
|
|
// search start is reset
|
|
assert_eq!(search_start.0, 0);
|
|
|
|
let trie = PrefixTrieNode::from_sorted_prefixes(IntoIterator::into_iter([
|
|
"arb", "arbre", "cat", "catto",
|
|
]));
|
|
check_prefixes(&trie, &search_start, "arbres", &["arb", "arbre"]);
|
|
check_prefixes(&trie, &search_start, "cattos", &["cat", "catto"]);
|
|
}
|
|
|
|
#[test]
|
|
fn test_execute_on_word_pairs_and_prefixes() {
|
|
let prefixes = PrefixTrieNode::from_sorted_prefixes(IntoIterator::into_iter([
|
|
"arb", "arbre", "cat", "catto",
|
|
]));
|
|
|
|
let mut serialised_bitmap123 = vec![];
|
|
let mut bitmap123 = RoaringBitmap::new();
|
|
bitmap123.insert(1);
|
|
bitmap123.insert(2);
|
|
bitmap123.insert(3);
|
|
CboRoaringBitmapCodec::serialize_into(&bitmap123, &mut serialised_bitmap123);
|
|
|
|
let mut serialised_bitmap456 = vec![];
|
|
let mut bitmap456 = RoaringBitmap::new();
|
|
bitmap456.insert(4);
|
|
bitmap456.insert(5);
|
|
bitmap456.insert(6);
|
|
CboRoaringBitmapCodec::serialize_into(&bitmap456, &mut serialised_bitmap456);
|
|
|
|
let mut serialised_bitmap789 = vec![];
|
|
let mut bitmap789 = RoaringBitmap::new();
|
|
bitmap789.insert(7);
|
|
bitmap789.insert(8);
|
|
bitmap789.insert(9);
|
|
CboRoaringBitmapCodec::serialize_into(&bitmap789, &mut serialised_bitmap789);
|
|
|
|
let mut serialised_bitmap_ranges = vec![];
|
|
let mut bitmap_ranges = RoaringBitmap::new();
|
|
bitmap_ranges.insert_range(63_000..65_000);
|
|
bitmap_ranges.insert_range(123_000..128_000);
|
|
CboRoaringBitmapCodec::serialize_into(&bitmap_ranges, &mut serialised_bitmap_ranges);
|
|
|
|
let word_pairs = [
|
|
(("healthy", "arbres", 1), &serialised_bitmap123),
|
|
(("healthy", "boat", 1), &serialised_bitmap123),
|
|
(("healthy", "ca", 1), &serialised_bitmap123),
|
|
(("healthy", "cats", 1), &serialised_bitmap456),
|
|
(("healthy", "cattos", 1), &serialised_bitmap123),
|
|
(("jittery", "cat", 1), &serialised_bitmap123),
|
|
(("jittery", "cata", 1), &serialised_bitmap456),
|
|
(("jittery", "catb", 1), &serialised_bitmap789),
|
|
(("jittery", "catc", 1), &serialised_bitmap_ranges),
|
|
(("healthy", "arbre", 2), &serialised_bitmap123),
|
|
(("healthy", "arbres", 2), &serialised_bitmap456),
|
|
(("healthy", "cats", 2), &serialised_bitmap789),
|
|
(("healthy", "cattos", 2), &serialised_bitmap_ranges),
|
|
(("healthy", "arbre", 3), &serialised_bitmap456),
|
|
(("healthy", "arbres", 3), &serialised_bitmap789),
|
|
];
|
|
|
|
let expected_result = [
|
|
(("healthy", "arb", 1), bitmap123.clone()),
|
|
(("healthy", "arbre", 1), bitmap123.clone()),
|
|
(("healthy", "cat", 1), &bitmap456 | &bitmap123),
|
|
(("healthy", "catto", 1), bitmap123.clone()),
|
|
(("jittery", "cat", 1), (&bitmap123 | &bitmap456 | &bitmap789 | &bitmap_ranges)),
|
|
(("healthy", "arb", 2), &bitmap123 | &bitmap456),
|
|
(("healthy", "arbre", 2), &bitmap123 | &bitmap456),
|
|
(("healthy", "cat", 2), &bitmap789 | &bitmap_ranges),
|
|
(("healthy", "catto", 2), bitmap_ranges.clone()),
|
|
];
|
|
|
|
let mut result = vec![];
|
|
|
|
let mut iter =
|
|
IntoIterator::into_iter(word_pairs).map(|((word1, word2, proximity), data)| {
|
|
((word1.as_bytes(), word2.as_bytes(), proximity), data.as_slice())
|
|
});
|
|
execute_on_word_pairs_and_prefixes(
|
|
&mut iter,
|
|
|iter| Ok(iter.next()),
|
|
&prefixes,
|
|
2,
|
|
|k, v| {
|
|
let (word1, prefix, proximity) = StrStrU8Codec::bytes_decode(k).unwrap();
|
|
let bitmap = CboRoaringBitmapCodec::bytes_decode(v).unwrap();
|
|
result.push(((word1.to_owned(), prefix.to_owned(), proximity.to_owned()), bitmap));
|
|
Ok(())
|
|
},
|
|
)
|
|
.unwrap();
|
|
|
|
for (x, y) in result.into_iter().zip(IntoIterator::into_iter(expected_result)) {
|
|
let ((actual_word1, actual_prefix, actual_proximity), actual_bitmap) = x;
|
|
let ((expected_word1, expected_prefix, expected_proximity), expected_bitmap) = y;
|
|
|
|
assert_eq!(actual_word1, expected_word1);
|
|
assert_eq!(actual_prefix, expected_prefix);
|
|
assert_eq!(actual_proximity, expected_proximity);
|
|
assert_eq!(actual_bitmap, expected_bitmap);
|
|
}
|
|
}
|
|
}
|