Question

我正在尝试从具有多个条件的表中更改数据，如下所示：

UPDATE field0 as f0
 SET f0.c=IIF(Table.Field="x","a",IFF(Table.Field="y","b","c"))
FROM (
  SELECT f2.b AS Field
  FROM (field1 as f1 INNER JOIN field2 as f2 ON f1.a=f2.a)
  INNER JOIN field0 as f00 f00.a=f1.a
) as Table
;

但它没有用，它说我的查询方式有问题。

我也尝试过这样：

UPDATE field0 as f0
SET f0.c=IIF(f0.a=ANY(
 SELECT f1.c
 FROM field1 as f1 INNER JOIN field2 as f2 ON f1.a=f2.a
 WHERE f2.b=4),"a",IIF(f0.a=ANY(
  SELECT f1.c
  FROM field1 as f1 INNER JOIN field2 as f2 ON f1.a=f2.a
  WHERE f2.b NOT NULL),"b","c"))
;

但是这个说查询不是可更新的查询：/

我不知道该怎么做，有什么帮助吗？

这是我发现的实际代码：UPDATE Flights AS F SET F.status = (SELECT IIF(DE.handeling_code=4,"canceled",IIF(DE.handeling_code IS NOT NULL,"on time ","late")) FROM Irregular_Events AS IE INNER JOIN Delay_Event AS DE ON IE.IE_code=DE.delay_code WHERE IE.flight_code=F.flight_code ORDER BY F.flight_code); 我试图这样做，但它说当我想使用查询：“操作必须使用可更新的查询”

这也是我的航班表数据（以简化的方式）： flight_code|flight_status -----------|------------- 1 | On time 2 | On time 3 | On time 4 | On time irregular_event表是这样的： IE_code|flight_code -------|----------- 1 | 2 2 | 4 delay_event表是这样的： delay_code|delay_reason ----------|------------ 1 | 1 2 | 4 延迟原因从1到3只是延迟，4是取消航班所以我需要将航班2状态更改为延迟，将航班4更改为取消。

很抱歉这个杂乱的问题是我第一次来这里，我真的需要帮助解决这个问题，请跟我一起轻松！

Answer 1

第二个Iif出错，你有IFF并且缺少嵌套Iif的关闭窗口。

也许你应该使用WHERE IN：

UPDATE field0 as f0
 SET f0.c=Iif(Table.Field="x","a",Iif(Table.Field="y","b","c"))
WHERE b IN (
  SELECT f2.b AS Field
  FROM (field1 as f1 INNER JOIN field2 as f2 ON f1.a=f2.a)
  INNER JOIN field0 as f00 f00.a=f1.a)

Answer 2

别介意我以某种方式得到了解决方案并做到了这一点： UPDATE Flights AS F, Irregular_Events AS IE, Delay_Event AS DE SET F.status = IIF(DE.handeling_code=4,"Canseled","Delayed") WHERE F.flight_code=IE.flight_code AND IE.IE_code=DE.delay_code; 它工作正常！

使用多个条件和子查询进行UPDATE查询

2 个答案: