[
https://issues.apache.org/jira/browse/IMPALA-11414?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Zoltán Borók-Nagy resolved IMPALA-11414.
----------------------------------------
Fix Version/s: Impala 4.2.0
Resolution: Fixed
> Off-by-one error in Parquet late materialization
> ------------------------------------------------
>
> Key: IMPALA-11414
> URL: https://issues.apache.org/jira/browse/IMPALA-11414
> Project: IMPALA
> Issue Type: Bug
> Components: Backend
> Reporter: Zoltán Borók-Nagy
> Assignee: Zoltán Borók-Nagy
> Priority: Major
> Fix For: Impala 4.2.0
>
>
> With PARQUET_LATE_MATERIALIZATION we can set the number of minimum
> consecutive rows that if filtered out, we avoid materialization of rows in
> other columns in parquet.
> E.g. if PARQUET_LATE_MATERIALIZATION is 10, and in a filtered column we find
> at least 10 consecutive rows that don't pass the predicates we avoid
> materializing the corresponding rows in the other columns.
> But due to an off-by-one error we actually only need
> (PARQUET_LATE_MATERIALIZATION - 1) consecutive elements. This means if we set
> PARQUET_LATE_MATERIALIZATION to one, then we need zero consecutive filtered
> out elements which leads to a crash/DCHECK. The bug is in the
> GetMicroBatches() algorithm when we produce the micro batches based on the
> selected rows.
> Setting PARQUET_LATE_MATERIALIZATION to 0 doesn't make sense so it shouldn't
> be allowed.
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
---------------------------------------------------------------------
To unsubscribe, e-mail: issues-all-unsubscr...@impala.apache.org
For additional commands, e-mail: issues-all-h...@impala.apache.org
