[ https://issues.apache.org/jira/browse/KYLIN-2841?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Shaofeng SHI updated KYLIN-2841: -------------------------------- Summary: LIMIT pushdown should be applied to subquery (was: LIMIT is buggy with subquery) > LIMIT pushdown should be applied to subquery > -------------------------------------------- > > Key: KYLIN-2841 > URL: https://issues.apache.org/jira/browse/KYLIN-2841 > Project: Kylin > Issue Type: Bug > Affects Versions: v2.1.0 > Reporter: Mu Kong > Assignee: zhengdong > Priority: Major > Labels: scope > Fix For: v2.6.0 > > Attachments: 0001-KYLIN-2841-LIMIT-is-buggy-with-subquery.patch, > image-2018-12-13-23-41-53-732.png, image-2018-12-13-23-45-06-271.png, > image-2018-12-14-00-05-19-114.png, image-2018-12-14-00-08-27-648.png, > image-2018-12-14-00-23-08-869.png, kylin-2841-1.txt, kylin-2841-2.txt, > kylin-2841-apply-patch.txt > > > Hi, all. > I found that limit in the web UI seems not behaving as expected. > When I run a query like the follows: > {code:sql} > SELECT > SUM(col3) AS col4, > SUM(col5) AS total_col5, > col1 > FROM > ( > SELECT > col1, > col2, > MAX(col3) AS col3, > COUNT(*) AS col5 > FROM db.table > WHERE col6 = 'somestring' > GROUP BY col1, col2 > ) > GROUP BY col1 > {code} > When I specify the limit as 50, the result has 19 records, and when I specify > the limit as 500000, there are 90+ records in the result and each record has > higher col4 and total_col5. > But for query that doesn't have subquery, the result remains the same no > matter how I change the limit. > I guess for the query with subquery, limit somehow limits the number of the > result from the inner query instead of the result of the outer query. -- This message was sent by Atlassian JIRA (v7.6.3#76005)