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Posted to issues@spark.apache.org by "Apache Spark (Jira)" <ji...@apache.org> on 2021/07/13 18:02:00 UTC

[jira] [Commented] (SPARK-28266) data duplication when `path` serde property is present

    [ https://issues.apache.org/jira/browse/SPARK-28266?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17380093#comment-17380093 ] 

Apache Spark commented on SPARK-28266:
--------------------------------------

User 'shardulm94' has created a pull request for this issue:
https://github.com/apache/spark/pull/33328

> data duplication when `path` serde property is present
> ------------------------------------------------------
>
>                 Key: SPARK-28266
>                 URL: https://issues.apache.org/jira/browse/SPARK-28266
>             Project: Spark
>          Issue Type: Bug
>          Components: Spark Core
>    Affects Versions: 2.2.0, 2.2.1, 2.2.2
>            Reporter: Ruslan Dautkhanov
>            Priority: Major
>              Labels: correctness
>
> Spark duplicates returned datasets when `path` serde is present in a parquet table. 
> Confirmed versions affected: Spark 2.2, Spark 2.3, Spark 2.4.
> Confirmed unaffected versions: Spark 2.1 and earlier (tested with Spark 1.6 at least).
> Reproducer:
> {code:python}
> >>> spark.sql("create table ruslan_test.test55 as select 1 as id")
> DataFrame[]
> >>> spark.table("ruslan_test.test55").explain()
> == Physical Plan ==
> HiveTableScan [id#16], HiveTableRelation `ruslan_test`.`test55`, org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe, [id#16]
> >>> spark.table("ruslan_test.test55").count()
> 1
> {code}
> (all is good at this point, now exist session and run in Hive for example - )
> {code:sql}
> ALTER TABLE ruslan_test.test55 SET SERDEPROPERTIES ( 'path'='hdfs://epsdatalake/hivewarehouse/ruslan_test.db/test55' )
> {code}
> So LOCATION and serde `path` property would point to the same location.
> Now see count returns two records instead of one:
> {code:python}
> >>> spark.table("ruslan_test.test55").count()
> 2
> >>> spark.table("ruslan_test.test55").explain()
> == Physical Plan ==
> *(1) FileScan parquet ruslan_test.test55[id#9] Batched: true, Format: Parquet, Location: InMemoryFileIndex[hdfs://epsdatalake/hivewarehouse/ruslan_test.db/test55, hdfs://epsdatalake/hive..., PartitionFilters: [], PushedFilters: [], ReadSchema: struct<id:int>
> >>>
> {code}
> Also notice that the presence of `path` serde property makes TABLE location 
> show up twice - 
> {quote}
> InMemoryFileIndex[hdfs://epsdatalake/hivewarehouse/ruslan_test.db/test55, hdfs://epsdatalake/hive..., 
> {quote}
> We have some applications that create parquet tables in Hive with `path` serde property
> and it makes data duplicate in query results. 
> Hive, Impala etc and Spark version 2.1 and earlier read such tables fine, but not Spark 2.2 and later releases.



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