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https://issues.apache.org/jira/browse/SPARK-21520?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

caoxuewen updated SPARK-21520:
------------------------------
    Description: 
Currently, Did a lot of special handling for non-deterministic projects and 
filters in optimizer. but not good enough. this patch add a new special case 
for non-deterministic projects and filters. Deal with that we only need to read 
user needs fields for non-deterministic projects and filters in optimizer.
For example, the fields of project contains nondeterministic function(rand 
function), after a executedPlan optimizer generated:

*HashAggregate(keys=[k#403L], functions=[partial_sum(cast(id#402 as bigint))], 
output=[k#403L, sum#800L])
+- Project [d004#607 AS id#402, FLOOR((rand(8828525941469309371) * 10000.0)) AS 
k#403L]
   +- HiveTableScan [c030#606L, d004#607, d005#608, d025#609, c002#610, 
d023#611, d024#612, c005#613L, c008#614, c009#615, c010#616, d021#617, 
d022#618, c017#619, c018#620, c019#621, c020#622, c021#623, c022#624, c023#625, 
c024#626, c025#627, c026#628, c027#629, ... 169 more fields], MetastoreRelation 
XXX_database, XXX_table

HiveTableScan will read all the fields from table. but we only need to ‘d004’ . 
it will affect the performance of task.


  was:
Currently, Did a lot of special handling for non-deterministic projects and 
filters in optimizer. but not good enough. this patch add a new special case 
for non-deterministic projects and filters. Deal with that we only need to read 
user needs fields for non-deterministic projects and filters in optimizer.



> Improvement a special case for non-deterministic projects and filters in 
> optimizer
> ----------------------------------------------------------------------------------
>
>                 Key: SPARK-21520
>                 URL: https://issues.apache.org/jira/browse/SPARK-21520
>             Project: Spark
>          Issue Type: Improvement
>          Components: SQL
>    Affects Versions: 2.3.0
>            Reporter: caoxuewen
>
> Currently, Did a lot of special handling for non-deterministic projects and 
> filters in optimizer. but not good enough. this patch add a new special case 
> for non-deterministic projects and filters. Deal with that we only need to 
> read user needs fields for non-deterministic projects and filters in 
> optimizer.
> For example, the fields of project contains nondeterministic function(rand 
> function), after a executedPlan optimizer generated:
> *HashAggregate(keys=[k#403L], functions=[partial_sum(cast(id#402 as 
> bigint))], output=[k#403L, sum#800L])
> +- Project [d004#607 AS id#402, FLOOR((rand(8828525941469309371) * 10000.0)) 
> AS k#403L]
>    +- HiveTableScan [c030#606L, d004#607, d005#608, d025#609, c002#610, 
> d023#611, d024#612, c005#613L, c008#614, c009#615, c010#616, d021#617, 
> d022#618, c017#619, c018#620, c019#621, c020#622, c021#623, c022#624, 
> c023#625, c024#626, c025#627, c026#628, c027#629, ... 169 more fields], 
> MetastoreRelation XXX_database, XXX_table
> HiveTableScan will read all the fields from table. but we only need to ‘d004’ 
> . it will affect the performance of task.



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