From 0462c20113d4565844c56e54affb92b8d0f29690 Mon Sep 17 00:00:00 2001
From: qinling0210 <88864212+qinling0210@users.noreply.github.com>
Date: Mon, 30 Mar 2026 18:47:10 +0800
Subject: [PATCH] Fix special characters in matching text of search() (#13852)

### What problem does this PR solve?

Fix special characters in matching text of search(). We should escape
some special characters(such as ?, *,:) before passing to matching_text
of search()

Fix https://github.com/infiniflow/ragflow/issues/13729

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)
---
 common/query_base.py       | 2 +-
 rag/nlp/query.py           | 8 +++++++-
 rag/utils/infinity_conn.py | 1 +
 3 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/common/query_base.py b/common/query_base.py
index eae44514f1..c728304639 100644
--- a/common/query_base.py
+++ b/common/query_base.py
@@ -32,7 +32,7 @@ class QueryBase(ABC):
 
     @staticmethod
     def sub_special_char(line):
-        return re.sub(r"([:\{\}/\[\]\-\*\"\(\)\|\+~\^])", r"\\\1", line).strip()
+        return re.sub(r"([:\{\}/\[\]\-\*\?\"\(\)\|\+~\^])", r"\\\1", line).strip()
 
     @staticmethod
     def rmWWW(txt):
diff --git a/rag/nlp/query.py b/rag/nlp/query.py
index 39b6b439d0..2f5807147c 100644
--- a/rag/nlp/query.py
+++ b/rag/nlp/query.py
@@ -41,8 +41,14 @@ class FulltextQueryer(QueryBase):
     def question(self, txt, tbl="qa", min_match: float = 0.6):
         original_query = txt
         txt = self.add_space_between_eng_zh(txt)
+
+        # Strip Infinity ESCAPABLE characters from the query.
+        #
+        # Infinity's search_lexer.l defines ESCAPABLE characters [\x20()^"'~*?:\\]
+        # If these characters appear unescaped in a query, Infinity's lexer will
+        # interpret them as special tokens, causing parsing errors.
         txt = re.sub(
-            r"[ :|\r\n\t,，。？?/`!！&^%%()\[\]{}<>]+",
+            r"[ :|\r\n\t,，。？?/`!！&^%%()\[\]{}<>*~'\"\\]+",
             " ",
             rag_tokenizer.tradi2simp(rag_tokenizer.strQ2B(txt.lower())),
         ).strip()
diff --git a/rag/utils/infinity_conn.py b/rag/utils/infinity_conn.py
index 1976e14270..c039a7f7c1 100644
--- a/rag/utils/infinity_conn.py
+++ b/rag/utils/infinity_conn.py
@@ -243,6 +243,7 @@ class InfinityConnection(InfinityConnectionBase):
                         for matchExpr in match_expressions:
                             if isinstance(matchExpr, MatchTextExpr):
                                 fields = ",".join(matchExpr.fields)
+                                self.logger.info(f"INFINITY search match_text: {matchExpr.matching_text}")
                                 builder = builder.match_text(
                                     fields,
                                     matchExpr.matching_text,