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https://issues.apache.org/jira/browse/PHOENIX-4287?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16236431#comment-16236431
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Mujtaba Chohan edited comment on PHOENIX-4287 at 11/2/17 7:24 PM:
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[~jamestaylor] At table creation time I didn't set
USE_STATS_FOR_PARALLELIZATION and as global setting it's set to false. Later I
turn it off as well with ALTER statement. Index is global.
was (Author: mujtabachohan):
[~jamestaylor] At table creation time I didn't set
USE_STATS_FOR_PARALLELIZATION and as global setting it's set to false. Index is
global.
> 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
> Priority: Major
> Labels: localIndex
> Fix For: 4.13.0, 4.12.1
>
> Attachments: PHOENIX-4287.patch, PHOENIX-4287_addendum.patch,
> PHOENIX-4287_addendum2.patch, PHOENIX-4287_addendum3.patch,
> PHOENIX-4287_addendum4.patch, PHOENIX-4287_v2.patch, PHOENIX-4287_v3.patch,
> PHOENIX-4287_v3_wip.patch, PHOENIX-4287_v4.patch
>
>
> 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}
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