diff --git a/markdown_sqlite.py b/markdown_sqlite.py
index f89c6a9..bb4893b 100644
--- a/markdown_sqlite.py
+++ b/markdown_sqlite.py
@@ -228,16 +228,21 @@ class MarkdownProcessor:
     def merge_structures(self, existing: Dict, new: Dict, document_id: int) -> None:
         def merge_recursive(existing_node, new_node, parent_uuid):
             if not existing_node:
+                print('#### This seems to be a new stuff...')
                 # This is a new node, insert it
+                print(f"##### inserting new heading: {new_node['title']}")
                 heading_uuid = self.insert_heading(new_node['level'], new_node['title'], parent_uuid, document_id, new_node['path'])
-                body_uuid = self.insert_body(new_node['content'], heading_uuid, document_id)
+                ##print(f"##### inserting new body with id: {heading_uuid}, :\n {new_node['content']}\n")
+                if new_node['content']:
+                    body_uuid = self.insert_body(new_node['content'], heading_uuid, document_id)
                 for child in new_node['children']:
                     merge_recursive(None, new[child], heading_uuid)
             else:
+                print('#### This seems to known ')
                 # Update existing node
                 self.update_heading(existing_node['uuid'], new_node['title'], new_node['level'], parent_uuid, new_node['path'])
                 self.update_body(existing_node['body_uuid'], new_node['content'], document_id)
-                
+                print('#### Does these update_body and update_heading methods work?')
                 # Process children
                 existing_children = {child['title']: child for child in existing_node['children']}
                 new_children = {child['title']: child for child in new_node['children']}
@@ -253,6 +258,7 @@ class MarkdownProcessor:
                         self.soft_delete_heading(child['uuid'])
 
         for new_root in new.values():
+            print('#### Found a chapter!')
             existing_root = next((node for node in existing.values() if node['path'] == new_root['path']), None)
             merge_recursive(existing_root, new_root, None)
 
@@ -274,10 +280,39 @@ class MarkdownProcessor:
     def insert_body(self, content: str, heading_uuid: str, document_id: int) -> str:
         body_uuid = str(uuid.uuid4())
         md5sum = hashlib.md5(content.encode()).hexdigest()
-        self.db_manager.cursor.execute('''
-            INSERT INTO body (uuid, content, heading_uuid, document_id, md5sum)
-            VALUES (?, ?, ?, ?, ?)
-        ''', (body_uuid, content, heading_uuid, document_id, md5sum))
+        print(f"###### Trying to insert body text with md5sum of: {md5sum} to uuid: {body_uuid}, with content: \n{content}\n")
+        
+        # Verify input parameters
+        if not all([content, heading_uuid, document_id]):
+            raise ValueError("Missing required parameters for insert_body")
+    
+        try:
+            # Check if heading_uuid exists
+            self.db_manager.cursor.execute("SELECT 1 FROM headings WHERE uuid = ?", (heading_uuid,))
+            if not self.db_manager.cursor.fetchone():
+                raise ValueError(f"heading_uuid {heading_uuid} does not exist in headings table")
+    
+            # Check if document_id exists
+            self.db_manager.cursor.execute("SELECT 1 FROM documents WHERE id = ?", (document_id,))
+            if not self.db_manager.cursor.fetchone():
+                raise ValueError(f"document_id {document_id} does not exist in documents table")
+    
+            # Insert the body
+            self.db_manager.cursor.execute('''
+                INSERT INTO body (uuid, content, heading_uuid, document_id, md5sum)
+                VALUES (?, ?, ?, ?, ?)
+            ''', (body_uuid, content, heading_uuid, document_id, md5sum))
+            
+            self.db_manager.conn.commit()
+            print(f"###### Successfully inserted body with uuid: {body_uuid}")
+        except sqlite3.Error as e:
+            print(f"An error occurred while inserting body: {e}")
+            self.db_manager.conn.rollback()
+            raise
+        except ValueError as e:
+            print(f"Validation error: {e}")
+            raise
+    
         return body_uuid
 
     def update_body(self, body_uuid: str, content: str, document_id: int) -> None:
@@ -583,4 +618,4 @@ def main():
     db_manager.close()
 
 if __name__ == '__main__':
-    main()
\ No newline at end of file
+    main()