diff --git a/astrbot/core/db/sqlite.py b/astrbot/core/db/sqlite.py
index 98e6af04e..65d68526e 100644
--- a/astrbot/core/db/sqlite.py
+++ b/astrbot/core/db/sqlite.py
@@ -128,24 +128,23 @@ class SQLiteDatabase(BaseDatabase):
         except sqlite3.ProgrammingError:
             c = self._get_conn(self.db_path).cursor()
 
-        where_clause = ""
-        if session_id or provider_type:
-            where_clause += " WHERE "
-            has = False
-            if session_id:
-                where_clause += f"session_id = '{session_id}'"
-                has = True
-            if provider_type:
-                if has:
-                    where_clause += " AND "
-                where_clause += f"provider_type = '{provider_type}'"
+        conditions = []
+        params = []
+
+        if session_id:
+            conditions.append("session_id = ?")
+            params.append(session_id)
+
+        if provider_type:
+            conditions.append("provider_type = ?")
+            params.append(provider_type)
+
+        sql = "SELECT * FROM llm_history"
+        if conditions:
+            sql += " WHERE " + " AND ".join(conditions)
+
+        c.execute(sql, params)
 
-        c.execute(
-            """
-            SELECT * FROM llm_history
-            """
-            + where_clause
-        )
         res = c.fetchall()
         histories = []
         for row in res:
diff --git a/astrbot/core/db/sqlite_init.sql b/astrbot/core/db/sqlite_init.sql
index 900f4f2c0..a1ebc54b5 100644
--- a/astrbot/core/db/sqlite_init.sql
+++ b/astrbot/core/db/sqlite_init.sql
@@ -38,11 +38,13 @@ CREATE TABLE IF NOT EXISTS atri_vision(
 );
 
 CREATE TABLE IF NOT EXISTS webchat_conversation(
-    user_id TEXT,
-    cid TEXT,
+    user_id TEXT, -- 会话 id
+    cid TEXT, -- 对话 id
     history TEXT,
     created_at INTEGER,
     updated_at INTEGER,
     title TEXT,
     persona_id TEXT
-);
\ No newline at end of file
+);
+
+PRAGMA encoding = 'UTF-8';
\ No newline at end of file
diff --git a/astrbot/core/pipeline/process_stage/method/llm_request.py b/astrbot/core/pipeline/process_stage/method/llm_request.py
index 872875e8f..8d606d9e5 100644
--- a/astrbot/core/pipeline/process_stage/method/llm_request.py
+++ b/astrbot/core/pipeline/process_stage/method/llm_request.py
@@ -128,7 +128,7 @@ class LLMRequestSubStage(Stage):
 
         # max context length
         if (
-            self.max_context_length != -1 # -1 为不限制
+            self.max_context_length != -1  # -1 为不限制
             and len(req.contexts) // 2 > self.max_context_length
         ):
             logger.debug("上下文长度超过限制，将截断。")