fix(sqllab): apply SQL_QUERY_MUTATOR in SQL Lab when MUTATE_AFTER_SPLIT is set

SQL Lab passed the default is_split=False to mutate_sql_based_on_config for
every block, so SQL_QUERY_MUTATOR fired only when MUTATE_AFTER_SPLIT=False and
never when True. Pass is_split based on whether the engine runs statements as
one block, matching the canonical usage in db_engine_specs and the new
execution engine, and thread the same flag through execute_sql_with_cursor so
the async (Celery) path is consistent. Adds unit tests for both the guard
semantics and the executor contract, plus a config note.

Closes #30169
Supersedes #34111

Co-authored-by: Lucas Wolkersdorfer <lucas.wolkersdorfer@rise-world.com>
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

superset/config.py

@@ -2005,6 +2005,9 @@ def SQL_QUERY_MUTATOR(  # pylint: disable=invalid-name,unused-argument  # noqa:
 # An example use case is if data has role based access controls, and you want to apply
 # a SET ROLE statement alongside every user query. Changing this variable maintains
 # functionality for both the SQL_Lab and Charts.
+# This applies consistently in SQL Lab: with MUTATE_AFTER_SPLIT = True the mutator runs
+# on each individual statement, and with MUTATE_AFTER_SPLIT = False it runs once on the
+# un-split query block.
 MUTATE_AFTER_SPLIT = False
 
 

superset/sql/execution/celery_task.py

@@ -445,6 +445,9 @@ def _execute_sql_statements(
                 log_query_fn=_make_log_query_fn(database),
                 check_stopped_fn=_make_check_stopped_fn(query),
                 execute_fn=_make_execute_fn(query, db_engine_spec),
+                # `blocks` is a single un-split block when the engine runs multiple
+                # statements as one; otherwise each block is an individual statement.
+                is_split=not db_engine_spec.run_multiple_statements_as_one,
             )
         except SoftTimeLimitExceeded as ex:
             query.status = QueryStatus.TIMED_OUT

superset/sql/execution/executor.py

@@ -101,6 +101,7 @@ def execute_sql_with_cursor(
     log_query_fn: Any | None = None,
     check_stopped_fn: Any | None = None,
     execute_fn: Any | None = None,
+    is_split: bool = True,
 ) -> list[tuple[str, SupersetResultSet | None, float, int]]:
     """
     Execute SQL statements with a cursor and return all result sets.
@@ -119,6 +120,10 @@ def execute_sql_with_cursor(
     :param execute_fn: Optional custom execute function. If not provided, uses
         database.db_engine_spec.execute(cursor, sql, database). Custom function
         should accept (cursor, sql) and handle execution.
+    :param is_split: Whether `statements` are individual split-out statements (True)
+        or a single un-split block (False, e.g. when the engine spec runs multiple
+        statements as one). Passed to the SQL mutator so `MUTATE_AFTER_SPLIT` can
+        decide whether to fire.
     :returns: List of (statement_sql, result_set, execution_time_ms, rowcount) tuples
         Returns empty list if stopped. Raises exception on error (fail-fast).
     """
@@ -140,7 +145,7 @@ def execute_sql_with_cursor(
         # Apply SQL mutation
         stmt_sql = database.mutate_sql_based_on_config(
             statement,
-            is_split=True,
+            is_split=is_split,
         )
 
         # Log query

superset/sql_lab.py

@@ -474,7 +474,7 @@ def execute_sql_statements(  # noqa: C901
     for statement in parsed_script.statements:
         apply_limit(query, statement)
 
-    # some databases (like BigQuery and Kusto) do not persist state across mmultiple
+    # some databases (like BigQuery and Kusto) do not persist state across multiple
     # statements if they're run separately (especially when using `NullPool`), so we run
     # the query as a single block.
     if db_engine_spec.run_multiple_statements_as_one:
@@ -517,8 +517,15 @@ def execute_sql_statements(  # noqa: C901
             query.set_extra_json_key("progress", msg)
             db.session.commit()
 
-            # Hook to allow environment-specific mutation (usually comments) to the SQL
-            query.executed_sql = database.mutate_sql_based_on_config(block)
+            # Hook to allow environment-specific mutation (usually comments) to the SQL.
+            # `is_split` reflects whether this block is an individual statement: when
+            # the engine runs everything as one block the SQL is not split, otherwise
+            # each block is a single split-out statement. This lets `MUTATE_AFTER_SPLIT`
+            # decide correctly whether the mutator fires here.
+            query.executed_sql = database.mutate_sql_based_on_config(
+                block,
+                is_split=not db_engine_spec.run_multiple_statements_as_one,
+            )
 
             try:
                 result_set = execute_query(query, cursor, log_params)

tests/unit_tests/models/core_test.py

@@ -262,6 +262,44 @@ def test_table_column_database() -> None:
     assert TableColumn(database=database).database is database
 
 
+@pytest.mark.parametrize(
+    "is_split,mutate_after_split,expect_mutated",
+    [
+        # A split-out statement is mutated only when the mutator is meant to run
+        # after the split, and an un-split block only when it runs before.
+        (True, True, True),
+        (True, False, False),
+        (False, False, True),
+        (False, True, False),
+    ],
+)
+def test_mutate_sql_based_on_config_respects_is_split(
+    app_context: None,
+    mocker: MockerFixture,
+    is_split: bool,
+    mutate_after_split: bool,
+    expect_mutated: bool,
+) -> None:
+    """
+    `mutate_sql_based_on_config` fires `SQL_QUERY_MUTATOR` only when the call
+    site's `is_split` matches the `MUTATE_AFTER_SPLIT` config. Regression guard
+    for issue #30169, where SQL Lab always passed the default `is_split=False`
+    and so never mutated when `MUTATE_AFTER_SPLIT=True`.
+    """
+    database = Database(database_name="db", sqlalchemy_uri="sqlite://")
+    mocker.patch.dict(
+        current_app.config,
+        {
+            "SQL_QUERY_MUTATOR": lambda sql, **kwargs: f"-- mutated\n{sql}",
+            "MUTATE_AFTER_SPLIT": mutate_after_split,
+        },
+    )
+
+    result = database.mutate_sql_based_on_config("SELECT 1", is_split=is_split)
+
+    assert result == ("-- mutated\nSELECT 1" if expect_mutated else "SELECT 1")
+
+
 def test_catalog_cache() -> None:
     """
     Test the catalog cache.

tests/unit_tests/sql/execution/test_executor.py

@@ -47,7 +47,7 @@ from superset.models.core import Database
 
 # Note: database, database_with_dml, mock_db_session fixtures and
 # mock_query_execution helper are imported from conftest.py
-from .conftest import mock_query_execution
+from .conftest import create_mock_cursor, mock_query_execution
 
 # =============================================================================
 # Basic Execution Tests
@@ -871,6 +871,45 @@ def test_execute_applies_sql_mutator(
     mutate_mock.assert_called()
 
 
+@pytest.mark.parametrize("is_split", [True, False])
+def test_execute_sql_with_cursor_forwards_is_split(
+    mocker: MockerFixture,
+    database: Database,
+    app_context: None,
+    mock_db_session: MagicMock,
+    mock_query: MagicMock,
+    is_split: bool,
+) -> None:
+    """
+    `execute_sql_with_cursor` must forward `is_split` to the SQL mutator.
+
+    `Database.mutate_sql_based_on_config` only fires `SQL_QUERY_MUTATOR` when
+    `is_split == MUTATE_AFTER_SPLIT`, so passing the wrong value silently skips
+    mutation (the SQL Lab bug behind issue #30169). This guards the contract.
+    """
+    from superset.sql.execution.executor import execute_sql_with_cursor
+
+    mutate_mock = mocker.patch.object(
+        database, "mutate_sql_based_on_config", side_effect=lambda sql, **kw: sql
+    )
+    mocker.patch.object(database.db_engine_spec, "execute")
+    mocker.patch.object(database.db_engine_spec, "fetch_data", return_value=[(1,)])
+    mocker.patch("superset.result_set.SupersetResultSet", return_value=MagicMock())
+
+    cursor = create_mock_cursor(["id"], data=[(1,)])
+
+    execute_sql_with_cursor(
+        database=database,
+        cursor=cursor,
+        statements=["SELECT id FROM t"],
+        query=mock_query,
+        is_split=is_split,
+    )
+
+    mutate_mock.assert_called_once()
+    assert mutate_mock.call_args.kwargs["is_split"] is is_split
+
+
 # =============================================================================
 # Progress Tracking Tests
 # =============================================================================