phoenix-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Lars Hofhansl (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (PHOENIX-258) Use skip scan when SELECT DISTINCT on leading row key column(s)
Date Wed, 01 Jun 2016 23:55:59 GMT

    [ https://issues.apache.org/jira/browse/PHOENIX-258?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15311408#comment-15311408
] 

Lars Hofhansl commented on PHOENIX-258:
---------------------------------------

Actually, so here's a case that does not work: 1, 2/0xff0xff, 3, 3. When we see the 2nd 3,
we'll seek to 2/0xff, which will miss the row with 2.
Fix coming.

> Use skip scan when SELECT DISTINCT on leading row key column(s)
> ---------------------------------------------------------------
>
>                 Key: PHOENIX-258
>                 URL: https://issues.apache.org/jira/browse/PHOENIX-258
>             Project: Phoenix
>          Issue Type: Task
>            Reporter: ryang-sfdc
>            Assignee: Lars Hofhansl
>             Fix For: 4.8.0
>
>         Attachments: 258-WIP.txt, 258-v1.txt, 258-v10.txt, 258-v11.txt, 258-v12.txt,
258-v13.txt, 258-v14.txt, 258-v15.txt, 258-v2.txt, 258-v3.txt, 258-v4.txt, 258-v5.txt, 258-v6.txt,
258-v7.txt, 258-v8.txt, 258-v9.txt, 258.txt, DistinctFixedPrefixFilter.java, in-clause.png
>
>
> create table(a varchar(32) not null, date date not null constraint pk primary key(a,date))
> [["PLAN"],["CLIENT PARALLEL 94-WAY FULL SCAN OVER foo"],["    SERVER AGGREGATE INTO ORDERED
DISTINCT ROWS BY [a]"],["CLIENT MERGE SORT"]]             
> We should skip scan.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Mime
View raw message