Hive SQL 逻辑 - case when 语句

Posted 2023-03-23

【中文标题】Hive SQL 逻辑 - case when 语句

【英文标题】：Hive SQL logic - case when statement

【发布时间】：2020-04-16 00:59:36

【问题描述】：

我的查询：

case 
   when upper(a.camp_name) like "%Event%" and (upper(a.camp_name) not like "%Event-WBR%" or upper(a.camp_name) not like "%Event-Webinar%") THEN "Field"
   else "Demand"
end as Tactic

期望的输出：

Event-WBR = Demand
Event = Field

实际输出：

Event-WBR = Field
Event = Field

【参考方案1】：

其实你应该把'or'换成'and'

case 
       when upper(a.camp_name) like "%Event%" and (upper(a.camp_name) not like "%Event-WBR%" and upper(a.camp_name) not like "%Event-Webinar%") THEN "Demand"
       else "Field"
    end as Tactic

但这里还有另外 2 个选项：

如果你只想为“事件”这个词做，你可以这样做

case 
   when upper(a.camp_name) like "%Event" and (upper(a.camp_name) not like "%Event-WBR%" or upper(a.camp_name) not like "%Event-Webinar%") THEN "Demand"
   else "Field"
end as Tactic

如果你只想排除这两个词，你可以这样做。

case 
   when upper(a.camp_name) like "%Event-WBR%" or (upper(a.camp_name) like "%Event-Webinar%" THEN "Field"
   else "Demand"
end as Tactic

【参考方案2】：

你可以使用两个whens：

(case when (upper(a.camp_name) not like "%Event-WBR%" or 
            upper(a.camp_name) not like "%Event-Webinar%"
           ) then 'Event'
      when upper(a.camp_name) like "%Event%" then 'Event'
      else 'Deman'
 end) as tactic