select 小技巧问题

Question

假设有一个表atablename|number
-----------
a              0
b              1
c              0
a              3
a              1
b              0写一个查询，把显示结果中是 0改为用 - 来显示name|number
-----------
a              -
b              1
c              -
a              3
a              1
b              -这个怎么做啊

Answer 1

select name,decode(number,0,'-') from atable;

Answer 2

楼上的类型会不一致吧，
select name,decode(to_char(number),'0','-',to_char(number)) nbr from atable;

Answer 3

SELECT name,decode(num,'0','-',num) FROM atable
-->这样写就可以了

Answer 4

技巧select name , case number字段  
                 when 0 then '-'
                 else to_char(number字段)
              end   g_number 
from table_name;

Answer 5

不把0转化为'0'也可以，Oracle会自动转化