oracle 如何在 Case 语句中使用 If 条件？
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时间：2020-09-10 03:59:49 来源:igfitidea点击:
How to use If condition inside a Case statement?
提问by Samurai
Below is my query. Is this righ?
以下是我的查询。这是对的吗？
SQL> select case when value in (1000) then null
2 when user in ('ABC') then user
3 when area in ('DENVER') then
4 if value = 2000 then 'Service1'
5 else value = 3000 then 'Service2'
6 end if
7 else null
8 end as num_code from service_usoc_ref;
if prin = 2000 then 'Omaha'
*
ERROR at line 4:
ORA-00905: missing keyword
Please help me.
请帮我。
回答by A.B.Cade
You can either put another case or use decode (as @madhu suggested):
您可以放置另一个案例或使用解码（如@madhu 建议的那样）：
select case
when value in (1000) then null
when user in ('ABC') then user
when area in ('DENVER') then
case when value = 2000 then 'Service1'
when value = 3000 then 'Service2'
end
else null
end as num_code
from service_usoc_ref;
回答by Maddy
This could help you
这可以帮助你
select case when value in (1000) then null
when user in ('ABC') then user
when area in ('DENVER') then
decode( value, 2000 , 'Service1',3000 , 'Service2', NULL) num_code
from service_usoc_ref;
