計算兩列中非 NULL 的行

Question

我正在嘗試比較 SQL 中的兩組：

create table my_counts
as select count(*) as total, 
          count(c.cookie) as first,
          count(l.cookie) as second, 
          count(l.cookie and c.cookie) as common
from (select distinct s.cookie from ...) c
full outer join
     (select distinct s.cookie from ...) l
on c.cookie = l.cookie;
select * from my_counts;

但是，上述失敗並出現此錯誤：

失敗： ClassCastException org.apache.hadoop.hive.serde2.objectinspector.primitive.WritableStringObjectInspector無法轉換為org.apache.hadoop.hive.serde2.objectinspector.primitive.BooleanObjectInspector

當然（假設上面的 SQL 語句做了我認為應該做的事情），我應該有total + common = first + second ，所以common列不是絕對必要的，但我仍然想知道是否有辦法計算行數其中兩列都是非NULL 。

Answer 1

AND - 是一個布爾運算符。 看起來cookie是一個字符串，而不是布爾值。 嘗試用這個替換count(l.cookie and c.cookie) ： count(case when l.cookie is not null and c.cookie is not null then 1 else NULL end) as common