Function build_sql_batch_view 

pub async fn build_sql_batch_view(
    def: &ViewDefinition,
    runtime: Arc<RuntimeEnv>,
    lake: Arc<DataLakeConnection>,
    view_factory: Arc<ViewFactory>,
    session_configurator: Arc<dyn SessionConfigurator>,
) -> Result<SqlBatchView, Error>

Builds the SqlBatchView a ViewDefinition describes. This is most of the validation – planning the extract query catches syntax errors, unknown tables and unknown columns, and yields the schema every later check inspects – so callers (the DDL executor, the registry loader) must call this before validate_view_definition, never after.