mysql union all 连表查询如何知道结果来自哪张表?

select
w.woType,
'NO_HIS' as dataFrom
from
workorder_complet_info w
where
w.workOrderNo = 'xxxxxx'
union all
select
w.woType,
'HIS' as dataFrom
from
workorder_complet_info_his w
where
w.workOrderNo = 'xxxxxx';

 

标红的为核心点