以下语法遵从postgres,我没有实际运行(我可以肯定的是:使用case语句可以完成你需要的功能)。 select a.goodscode, a.goodsname, a.stylecode, case a.stylecode when 1 then b.styleclassname else c.styleclassname end as styleclassname from a, b, c where a.classcode = b.styleclasscode and a.classcode = c.styleclasscode
select a.goodscode,
a.goodsname,
a.stylecode,
case a.stylecode when 1 then b.styleclassname
else c.styleclassname end as styleclassname
from a, b, c
where a.classcode = b.styleclasscode and
a.classcode = c.styleclasscode