diff --git a/src/storage.rs b/src/storage.rs
index 0e3639b..8fae82a 100644
--- a/src/storage.rs
+++ b/src/storage.rs
@@ -1761,13 +1761,14 @@ impl Database {
             )?;
             let chunks_to_shred: Vec<(u32, usize)> = stmt
                 .query_map(params![node_id, max_chunk_index], |row| {
-                    Ok((row.get(0)?, row.get::<_, usize>(1)?))
+                    let idx: u32 = row.get(0)?;
+                    let len: usize = row.get::<_, Option<usize>>(1)?.unwrap_or(0);
+                    Ok((idx, len))
                 })?
-                .filter_map(|r| r.ok())
-                .collect();
+                .collect::<std::result::Result<Vec<_>, rusqlite::Error>>()?;
 
             let mut update_stmt = tx.prepare(
-                "UPDATE chunks SET nonce = ?1, tag = ?2, ciphertext = ?3 WHERE node_id = ?4 AND chunk_index = ?5",
+                "UPDATE chunks SET nonce = ?1, tag = ?2, ciphertext = ?3, generation = 0 WHERE node_id = ?4 AND chunk_index = ?5",
             )?;
 
             for (idx, len) in chunks_to_shred {
@@ -1778,13 +1779,13 @@ impl Database {
                 OsRng.fill_bytes(&mut dummy_tag);
                 OsRng.fill_bytes(&mut dummy_payload);
 
-                let _ = update_stmt.execute(params![
+                update_stmt.execute(params![
                     dummy_nonce.as_slice(),
                     dummy_tag.as_slice(),
                     dummy_payload.as_slice(),
                     node_id,
                     idx
-                ]);
+                ])?;
             }
         }
 
@@ -2597,6 +2598,43 @@ mod tests {
         assert_ne!(chunk.tag, c_tag, "Tag muss überschrieben sein");
     }
 
+    #[test]
+    fn test_v09_truncate_chunks_after_shreds_before_deletion() {
+        let db = Database::open_in_memory().unwrap();
+        let salt = [1u8; 16];
+        let kdf_params = KdfParams::default();
+        let wrapped_dek = vec![2u8; 32];
+        let nonce = [3u8; 12];
+        let tag = [4u8; 16];
+
+        db.init_schema(&salt, &kdf_params, &wrapped_dek, &nonce, &tag)
+            .unwrap();
+        let root = db.resolve_path("/").unwrap().expect("Root");
+        let file = db.create_node(root.id, "truncate_test.dat", false).unwrap();
+
+        let payload_0 = b"CHUNK_ZERO_MUST_SURVIVE";
+        let payload_1 = b"CHUNK_ONE_MUST_BE_SHREDDED_AND_DELETED";
+        let payload_2 = b"CHUNK_TWO_MUST_BE_SHREDDED_AND_DELETED";
+
+        db.write_chunk(file.id, 0, 0, &[1u8; 12], &[2u8; 16], payload_0)
+            .unwrap();
+        db.write_chunk(file.id, 1, 0, &[3u8; 12], &[4u8; 16], payload_1)
+            .unwrap();
+        db.write_chunk(file.id, 2, 0, &[5u8; 12], &[6u8; 16], payload_2)
+            .unwrap();
+
+        // Kürze alle Chunks nach Index 0 (also Chunks 1 und 2)
+        db.truncate_chunks_after(file.id, 0).unwrap();
+
+        // Chunk 0 muss unberührt geblieben sein
+        let c0 = db.read_chunk(file.id, 0).unwrap().expect("Chunk 0 survives");
+        assert_eq!(c0.ciphertext, payload_0);
+
+        // Chunks 1 und 2 müssen gelöscht sein
+        assert!(db.read_chunk(file.id, 1).unwrap().is_none());
+        assert!(db.read_chunk(file.id, 2).unwrap().is_none());
+    }
+
     #[test]
     fn test_hidden_vault_isolation_and_filename_encryption() {
         let db = Database::open_in_memory().unwrap();