https://github.com/apache/incubator-superset/blob/master/superset/assets/src/datasource/DatasourceEditor.jsx#L683 -L695
<Button bsStyle="primary" onClick={this.syncMetadata} className="sync-from-source" disabled={!!datasource.sql} tooltip={ datasource.sql ? t('This option is not yet available for views') : null } > {t('Sync columns from source')} </Button>