[KYLIN-3402] kylin not support count distinct in sub

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Assignee: Unassigned
• Reporter: Lemont
• Created: 08/Jun/18 16:29
• Updated: 15/Jun/18 10:00
• Resolved: 15/Jun/18 10:00

Description

why kylin not support count  distinct in innermost sub-query.To deal with it I have to try another way to write sql,it's very complicated.

For example id is the Dimensions：

select count( DISTINCT case when condition = 1 then id end) idCount
from (
select condition,id
from table

where xxx

group by xxx
)

To support count distinct I hava to rewrite it to:

select count(1) from (

select  case when condition = 1 then id end idCount
from (
select condition,id
from table 

where xxx

group by xxx
) group by idCount

)

I feel so bad with it ,Is there a better solution?

 Thanks to every answer