drill-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Jacques Nadeau (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (DRILL-3209) [Umbrella] Plan reads of Hive tables as native Drill reads when a native reader for the underlying table format exists
Date Tue, 22 Sep 2015 23:18:04 GMT

    [ https://issues.apache.org/jira/browse/DRILL-3209?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14903645#comment-14903645
] 

Jacques Nadeau commented on DRILL-3209:
---------------------------------------

Agree on the HiveNativeDrillScan approach.

> [Umbrella] Plan reads of Hive tables as native Drill reads when a native reader for the
underlying table format exists
> ----------------------------------------------------------------------------------------------------------------------
>
>                 Key: DRILL-3209
>                 URL: https://issues.apache.org/jira/browse/DRILL-3209
>             Project: Apache Drill
>          Issue Type: Improvement
>          Components: Query Planning & Optimization, Storage - Hive
>            Reporter: Jason Altekruse
>            Assignee: Jason Altekruse
>             Fix For: 1.2.0
>
>
> All reads against Hive are currently done through the Hive Serde interface. While this
provides the most flexibility, the API is not optimized for maximum performance while reading
the data into Drill's native data structures. For Parquet and Text file backed tables, we
can plan these reads as Drill native reads. Currently reads of these file types provide untyped
data. While parquet has metadata in the file we currently do not make use of the type information
while planning. For text files we read all of the files as lists of varchars. In both of these
cases, casts will need to be injected to provide the same datatypes provided by the reads
through the SerDe interface.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Mime
View raw message