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Posted to issues@hive.apache.org by "Zoltan Haindrich (Jira)" <ji...@apache.org> on 2020/01/31 15:43:00 UTC
[jira] [Updated] (HIVE-22811) Stat based min/max aggregates are not
serviced from colstats in nested cases
[ https://issues.apache.org/jira/browse/HIVE-22811?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Zoltan Haindrich updated HIVE-22811:
------------------------------------
Summary: Stat based min/max aggregates are not serviced from colstats in nested cases (was: Statistics are not exploit in nested cases)
> Stat based min/max aggregates are not serviced from colstats in nested cases
> ----------------------------------------------------------------------------
>
> Key: HIVE-22811
> URL: https://issues.apache.org/jira/browse/HIVE-22811
> Project: Hive
> Issue Type: Improvement
> Components: Statistics
> Reporter: Zoltan Haindrich
> Priority: Major
>
> The statsOptimizer is able to use min/max/etc values to service simple queries
> {code}
> (select max(id) from t t0)
> {code}
> however the same doesn't happen for queries like:
> {code}
> explain select * from u where u.id>(select max(id) from t t0);
> {code}
> explain:
> {code}
> | Plan optimized by CBO. |
> | |
> | Vertex dependency in root stage |
> | Reducer 3 <- Map 1 (BROADCAST_EDGE), Map 2 (CUSTOM_SIMPLE_EDGE) |
> | |
> | Stage-0 |
> | Fetch Operator |
> | limit:-1 |
> | Stage-1 |
> | Reducer 3 vectorized |
> | File Output Operator [FS_31] |
> | Select Operator [SEL_30] (rows=1 width=8) |
> | Output:["_col0","_col1"] |
> | Filter Operator [FIL_29] (rows=1 width=12) |
> | predicate:(_col0 > _col2) |
> | Map Join Operator [MAPJOIN_28] (rows=3 width=12) |
> | Conds:(Inner),Output:["_col0","_col1","_col2"] |
> | <-Map 1 [BROADCAST_EDGE] vectorized |
> | BROADCAST [RS_25] |
> | Select Operator [SEL_24] (rows=3 width=8) |
> | Output:["_col0","_col1"] |
> | Filter Operator [FIL_23] (rows=3 width=8) |
> | predicate:id is not null |
> | TableScan [TS_0] (rows=3 width=8) |
> | default@u,u,Tbl:COMPLETE,Col:COMPLETE,Output:["id","cnt"] |
> | <-Filter Operator [FIL_27] (rows=1 width=4) |
> | predicate:_col0 is not null |
> | Group By Operator [GBY_26] (rows=1 width=4) |
> | Output:["_col0"],aggregations:["max(VALUE._col0)"] |
> | <-Map 2 [CUSTOM_SIMPLE_EDGE] vectorized |
> | PARTITION_ONLY_SHUFFLE [RS_22] |
> | Group By Operator [GBY_21] (rows=1 width=4) |
> | Output:["_col0"],aggregations:["max(id)"] |
> | Select Operator [SEL_20] (rows=4 width=4) |
> | Output:["id"] |
> | TableScan [TS_3] (rows=4 width=4) |
> | default@t,t0,Tbl:COMPLETE,Col:COMPLETE,Output:["id"] |
> {code}
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