你要怎么嵌套?select decode(decode(sign(a),1,100),100,5)
from
(select 1 as a,'a' as b from dual
union select 2 ,'b' from dual
) a--上面是,第一次判断是否大于0,大于0的话,就变成100,
第二次再判断是否是100,如果是100,就变成5.
from
(select 1 as a,'a' as b from dual
union select 2 ,'b' from dual
) a--上面是,第一次判断是否大于0,大于0的话,就变成100,
第二次再判断是否是100,如果是100,就变成5.
if (x=1 and y =2 )
return 1
else
return 2
这还是ANSI SQL呢, 拿到哪都能用
when t.item_id = '100006' then
'OK'
when t.item_id = '100005' then
'NO'
else
'OOOO'
end ) AS item_id
from tmpb_item_work t