docs: clarify async kernel rowcount requirement

Signed-off-by: Aakash Saravanan <aakash.saravanan@databricks.com>

Author: aakash-saravanan-db

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 # Unreleased
 - Fix inline parameters (`use_inline_params=True`) so a sequence directly after `IN` renders as a list again: `x IN %(ids)s` renders as `x IN (1,2,3)` instead of `x IN ARRAY(1,2,3)`, which Spark rejects. Inside the list, tuples render as rows for a multi-column `IN`, and a `set` or `frozenset` is accepted again. Sequences anywhere else still render as `ARRAY(...)` ([#629](https://github.com/databricks/databricks-sql-python/issues/629))
+- Report `cursor.rowcount` after asynchronous DML completes. With `use_kernel=True`, this requires a kernel release containing async affected-row count support; kernel 1.4.0 continues to report `-1`.
 
 # 4.9.0 (2026-11-04)
 - Upgrade Databricks SQL Kernel to 1.4.0, which keeps Lakehouse Real-Time session affinity and flushes shared telemetry only after the final session closes.

src/databricks/sql/backend/kernel/client.py

@@ -967,6 +967,8 @@ def get_execution_result(
         # result-set construction fails after a successful await.
         try:
             result_set = self._make_result_set(stream, cursor, command_id)
+            # Older kernel wheels do not expose this value. Keep them compatible
+            # while allowing a newer binding to populate async rowcount.
             result_set.num_modified_rows = getattr(handle, "num_modified_rows", None)
             return result_set
         except Exception as exc: