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https://issues.apache.org/jira/browse/SPARK-11153?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14961147#comment-14961147
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Michael Armbrust commented on SPARK-11153:
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Its actually corrupted statistics in data that is written? Does parquet write
the version in the metadata? Should we actually be turning this off based on
writer version?
> Turns off Parquet filter push-down for string and binary columns
> ----------------------------------------------------------------
>
> Key: SPARK-11153
> URL: https://issues.apache.org/jira/browse/SPARK-11153
> Project: Spark
> Issue Type: Bug
> Components: SQL
> Affects Versions: 1.5.0, 1.5.1
> Reporter: Cheng Lian
> Assignee: Cheng Lian
> Priority: Blocker
>
> Due to PARQUET-251, {{BINARY}} columns in existing Parquet files may be
> written with corrupted statistics information. This information is used by
> filter push-down optimization. Since Spark 1.5 turns on Parquet filter
> push-down by default, we may end up with wrong query results. PARQUET-251 has
> been fixed in parquet-mr 1.8.1, but Spark 1.5 is still using 1.7.0.
> This affects all Spark SQL data types that can be mapped to Parquet
> {{BINARY}}, namely:
> - {{StringType}}
> - {{BinaryType}}
> - {{DecimalType}} (but Spark SQL doesn't support pushing down {{DecimalType}}
> columns for now.)
> To avoid wrong query results, we should disable filter push-down for columns
> of {{StringType}} and {{BinaryType}} until we upgrade to parquet-mr 1.8.
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