diff --git a/backend/app/data/source_objects.py b/backend/app/data/source_objects.py
index b938a7d4..65d78ee5 100644
--- a/backend/app/data/source_objects.py
+++ b/backend/app/data/source_objects.py
@@ -886,8 +886,9 @@ async def search_index(session: AsyncSession, row: Any, query: str, *, limit: in
         return [], 0
     key = name_key(text.rsplit(".", 1)[-1])
     filt = (*_scope_filter(row.id, index_schema(row)), SourceObject.removed_at.is_(None),
+            # 名字比的是 name_key（ASCII 已转小写）；注释要不分大小写：SQLite 的 LIKE 本来就不分（ASCII），PostgreSQL 分
             or_(SourceObject.name_key.contains(key, autoescape=True),
-                SourceObject.comment.contains(text, autoescape=True)))
+                SourceObject.comment.icontains(text, autoescape=True)))
     total = int((await session.execute(select(func.count()).select_from(SourceObject).where(*filt))).scalar() or 0)
     rows = (await session.execute(
         select(SourceObject.name, SourceObject.name_key, SourceObject.kind, SourceObject.comment,
diff --git a/backend/app/memory/kb.py b/backend/app/memory/kb.py
index a324d973..9c976e63 100644
--- a/backend/app/memory/kb.py
+++ b/backend/app/memory/kb.py
@@ -399,7 +399,8 @@ async def list_collections(session: AsyncSession) -> list[dict[str, Any]]:
             func.sum(Document.chunk_count),
         ).group_by(Document.collection)
     )
+    # sum 在 PostgreSQL 上给的是 numeric（驱动交回 Decimal），SQLite 给整数：一律转成 int
     return [
-        {"collection": name, "documents": docs, "chunks": chunks or 0}
+        {"collection": name, "documents": int(docs), "chunks": int(chunks or 0)}
         for name, docs, chunks in rows
     ]