求助 SQL 语句

Question

try:
select 
a,b,sum(decode(c,1,d,0)),sum(decode(c,2,d,0)),sum(decode(c,3,d,0)),sum(decode(c,4,d,0))
from tab
group by a,b

Answer 1

select a,b,sum(decode(c),1,d,0),sum(decode(c),2,d,0),sum(decode(c),3,d,0),sum(decode(c),4,d,0)
from table_name
group by a,b

Answer 2

是:
select a,b,sum(decode(c,1,d,0)),sum(decode(c,2,d,0)),sum(decode(c,3,d,0)),sum(decode(c,4,d,0))
from table_name
group by a,b