From 784008997ba3fa874e457401b761db67f223a69c Mon Sep 17 00:00:00 2001
From: Jyong <76649700+JohnJyong@users.noreply.github.com>
Date: Wed, 10 Dec 2025 18:45:43 +0800
Subject: [PATCH] fix parent-child check when child chunk is not exist (#29426)

---
 api/core/rag/datasource/retrieval_service.py | 19 ++++++++++++++-----
 api/services/dataset_service.py              |  2 ++
 2 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/api/core/rag/datasource/retrieval_service.py b/api/core/rag/datasource/retrieval_service.py
index e4ca25b46b..a139fba4d0 100644
--- a/api/core/rag/datasource/retrieval_service.py
+++ b/api/core/rag/datasource/retrieval_service.py
@@ -451,12 +451,21 @@ class RetrievalService:
                                     "position": child_chunk.position,
                                     "score": document.metadata.get("score", 0.0),
                                 }
-                                segment_child_map[segment.id]["child_chunks"].append(child_chunk_detail)
-                                segment_child_map[segment.id]["max_score"] = max(
-                                    segment_child_map[segment.id]["max_score"], document.metadata.get("score", 0.0)
-                                )
+                                if segment.id in segment_child_map:
+                                    segment_child_map[segment.id]["child_chunks"].append(child_chunk_detail)
+                                    segment_child_map[segment.id]["max_score"] = max(
+                                        segment_child_map[segment.id]["max_score"], document.metadata.get("score", 0.0)
+                                    )
+                                else:
+                                    segment_child_map[segment.id] = {
+                                        "max_score": document.metadata.get("score", 0.0),
+                                        "child_chunks": [child_chunk_detail],
+                                    }
                             if attachment_info:
-                                segment_file_map[segment.id].append(attachment_info)
+                                if segment.id in segment_file_map:
+                                    segment_file_map[segment.id].append(attachment_info)
+                                else:
+                                    segment_file_map[segment.id] = [attachment_info]
                     else:
                         # Handle normal documents
                         segment = None
diff --git a/api/services/dataset_service.py b/api/services/dataset_service.py
index 00f06e9405..7841b8b33d 100644
--- a/api/services/dataset_service.py
+++ b/api/services/dataset_service.py
@@ -673,6 +673,8 @@ class DatasetService:
         Returns:
             str: Action to perform ('add', 'remove', 'update', or None)
         """
+        if "indexing_technique" not in data:
+            return None
         if dataset.indexing_technique != data["indexing_technique"]:
             if data["indexing_technique"] == "economy":
                 # Remove embedding model configuration for economy mode