Detect tables that are not present in the mapping file

Introduces #1221

src/databricks/labs/ucx/hive_metastore/table_migrate.py

@@ -57,6 +57,13 @@ def __init__(
         self._seen_tables: dict[str, str] = {}
         self._principal_grants = principal_grants
 
+    def not_migrated_refresh(self) -> list[Table]:
+        table_rows: list[Table] = []
+        for crawled_table in self._tc.snapshot():
+            if not self.is_migrated(crawled_table.database, crawled_table.name):
+                table_rows.append(crawled_table)
+        return table_rows # depending on how to publish this data, we may need to convert it to other forms to able to show it in the dashboard
+
     def index(self):
         return self._migration_status_refresher.index()
 

src/databricks/labs/ucx/hive_metastore/workflows.py

@@ -73,6 +73,10 @@ def refresh_migration_status(self, ctx: RuntimeContext):
         """Refresh the migration status to present it in the dashboard."""
         ctx.tables_migrator.index_full_refresh()
 
+    @job_task(job_cluster="table_migration", depends_on=[migrate_external_tables_sync, migrate_dbfs_root_delta_tables, migrate_dbfs_root_non_delta_tables,migrate_views])
+    def refresh_not_migrated_status(self, ctx: RuntimeContext):
+        """Refresh the not migrated tables status to present it in the dashboard."""
+        ctx.tables_migrator.not_migrated_refresh()
 
 class MigrateHiveSerdeTablesInPlace(Workflow):
     def __init__(self):

tests/unit/hive_metastore/test_workflows.py

@@ -70,3 +70,8 @@ def test_refresh_migration_status_is_refreshed(run_workflow, workflow):
     assert "DELETE FROM hive_metastore.ucx.migration_status" in ctx.sql_backend.queries
     assert "SHOW DATABASES" in ctx.sql_backend.queries
     # No "SHOW TABLE FROM" query as table are not mocked
+
+#TODO: create a unit test for the new task in the workflow
+# def test_refresh_not_migrated_status_is_refreshed(run_workflow):
+#     ctx = run_workflow(TableMigration.refresh_not_migrated_status)
+#     # ctx.workspace_client.catalogs.list.assert_called()