You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@phoenix.apache.org by "Mujtaba Chohan (JIRA)" <ji...@apache.org> on 2017/10/13 21:09:00 UTC

[jira] [Assigned] (PHOENIX-4287) Incorrect aggregate query results when stats are disable for parallelization

     [ https://issues.apache.org/jira/browse/PHOENIX-4287?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Mujtaba Chohan reassigned PHOENIX-4287:
---------------------------------------

    Assignee: Samarth Jain

> Incorrect aggregate query results when stats are disable for parallelization
> ----------------------------------------------------------------------------
>
>                 Key: PHOENIX-4287
>                 URL: https://issues.apache.org/jira/browse/PHOENIX-4287
>             Project: Phoenix
>          Issue Type: Bug
>    Affects Versions: 4.12.0
>         Environment: HBase 1.3.1
>            Reporter: Mujtaba Chohan
>            Assignee: Samarth Jain
>
> With {{phoenix.use.stats.parallelization}} set to {{false}}, aggregate query returns incorrect results when stats are available.
> With local index and stats disabled for parallelization:
> {noformat}
> explain select count(*) from TABLE_T;
> +-------------------------------------------------------------------------------------------------------+-----------------+----------------+-----------+
> |                                                 PLAN                                                  | EST_BYTES_READ  | EST_ROWS_READ  |  EST_INFO |
> +-------------------------------------------------------------------------------------------------------+-----------------+----------------+-----------+
> | CLIENT 0-CHUNK 332170 ROWS 625043899 BYTES PARALLEL 0-WAY RANGE SCAN OVER TABLE_T [1]  | 625043899       | 332170         | 150792825 |
> |     SERVER FILTER BY FIRST KEY ONLY                                                                   | 625043899       | 332170         | 150792825 |
> |     SERVER AGGREGATE INTO SINGLE ROW                                                                  | 625043899       | 332170         | 150792825 |
> +-------------------------------------------------------------------------------------------------------+-----------------+----------------+-----------+
> select count(*) from TABLE_T;
> +-----------+
> | COUNT(1)  |
> +-----------+
> | 0         |
> +-----------+
> {noformat}
> Using data table
> {noformat}
> explain select /*+NO_INDEX*/ count(*) from TABLE_T;
> +--------------------------------------------------------------------------------------------------+-----------------+----------------+----------------+
> |                                               PLAN                                               | EST_BYTES_READ  | EST_ROWS_READ  |  EST_INFO_TS   |
> +--------------------------------------------------------------------------------------------------+-----------------+----------------+----------------+
> | CLIENT 2-CHUNK 332151 ROWS 438492470 BYTES PARALLEL 1-WAY FULL SCAN OVER TABLE_T  | 438492470       | 332151         | 1507928257617  |
> |     SERVER FILTER BY FIRST KEY ONLY                                                              | 438492470       | 332151         | 1507928257617  |
> |     SERVER AGGREGATE INTO SINGLE ROW                                                             | 438492470       | 332151         | 1507928257617  |
> +--------------------------------------------------------------------------------------------------+-----------------+----------------+----------------+
> select /*+NO_INDEX*/ count(*) from TABLE_T;
> +-----------+
> | COUNT(1)  |
> +-----------+
> | 14        |
> +-----------+
> {noformat}
> Without stats available, results are correct:
> {noformat}
> explain select /*+NO_INDEX*/ count(*) from TABLE_T;
> +----------------------------------------------------------------------+-----------------+----------------+--------------+
> |                                 PLAN                                 | EST_BYTES_READ  | EST_ROWS_READ  | EST_INFO_TS  |
> +----------------------------------------------------------------------+-----------------+----------------+--------------+
> | CLIENT 2-CHUNK PARALLEL 1-WAY FULL SCAN OVER TABLE_T  | null            | null           | null         |
> |     SERVER FILTER BY FIRST KEY ONLY                                  | null            | null           | null         |
> |     SERVER AGGREGATE INTO SINGLE ROW                                 | null            | null           | null         |
> +----------------------------------------------------------------------+-----------------+----------------+--------------+
> select /*+NO_INDEX*/ count(*) from TABLE_T;
> +-----------+
> | COUNT(1)  |
> +-----------+
> | 333327    |
> +-----------+
> {noformat}



--
This message was sent by Atlassian JIRA
(v6.4.14#64029)