從選擇語句返回值

Question

我有這個查詢字符串

  select a.name, a.address
  from table_main a
  where a.id=3345

對於此查詢，我嘗試添加a.amount（如果它為null）以返回零（如果未返回某個值）

 select a.name, a.addres, isnull(a.amount, 0) else 333
 from table_main a
 where a.id=3345

任何想法如何解決此問題，以便如果a.amount為null，則返回零（如果不等於返回值，即333）

Answer 1

您可以使用case陳述

select a.name, 
       a.addres,
       case when a.amount is null 
            then 0 
            else 333
       end as amount_check
from table_main a
wher a.id = 3345

Answer 2

select a.name, a.addres,
      case when a.amount is null then 0 else 333 end amount 
 from table_main a
 wher a.id=3345

Answer 3

試試這個（Use Case-When語句）

select a.name, a.addres, case when a.amount is NULL then 0 else 333 end as Amount
from table_main a
wher a.id=3345

Answer 4

您需要將其包含在CASE語句中

SELECT a.NAME,
   a.addres,
   CASE 
      WHEN a.amount IS NULL
         THEN 0
      ELSE 333
   END
FROM table_main a where a.id = 3345

Answer 5

嘗試這個：

select a.name, a.addres,
case when a.amount is null then 0 else 333 end
from table_main a where a.id=3345