From 1163f390b387d6dd59673b1be9aff10373ca5662 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Cl=C3=A9ment=20Renault?= <renault.cle@gmail.com>
Date: Fri, 20 Dec 2019 16:36:37 +0100
Subject: [PATCH] Restrict FST search to the first letter of the word

---
 meilisearch-core/src/bucket_sort.rs | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/meilisearch-core/src/bucket_sort.rs b/meilisearch-core/src/bucket_sort.rs
index 7148f6261..a0609d30d 100644
--- a/meilisearch-core/src/bucket_sort.rs
+++ b/meilisearch-core/src/bucket_sort.rs
@@ -467,7 +467,13 @@ fn fetch_matches<'txn, 'tag>(
         dfa_time += before_dfa.elapsed();
 
         let mut number_of_words = 0;
-        let mut stream = words.search(&dfa).into_stream();
+
+        let byte = query.as_bytes()[0];
+        let mut stream = if byte == u8::max_value() {
+            words.search(&dfa).ge(&[byte]).into_stream()
+        } else {
+            words.search(&dfa).ge(&[byte]).lt(&[byte + 1]).into_stream()
+        };
 
         // while let Some(input) = stream.next() {
         loop {