hive-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Mithun Radhakrishnan (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (HIVE-13509) HCatalog getSplits should ignore the partition with invalid path
Date Wed, 13 Apr 2016 23:03:25 GMT

    [ https://issues.apache.org/jira/browse/HIVE-13509?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15240190#comment-15240190
] 

Mithun Radhakrishnan commented on HIVE-13509:
---------------------------------------------

+[~daijy], [~rohini].

One possible concern is the disconnect between Hive and Pig:
# When one attempts to consume a *non-existent* directory (i.e. not just an empty directory)
through Pig, one gets a failure.
# When one attempts to consume a non-existent partition (e.g. {{dt='3016-04-13'}}) in Hive,
via  an unsatisfied partition-predicate, the query runs successfully (and returns nothing).

In ETL jobs using Pig, we might actually prefer a failure when the input data isn't available.
Wouldn't this fix break those semantics for Pig?

> HCatalog getSplits should ignore the partition with invalid path
> ----------------------------------------------------------------
>
>                 Key: HIVE-13509
>                 URL: https://issues.apache.org/jira/browse/HIVE-13509
>             Project: Hive
>          Issue Type: Improvement
>          Components: HCatalog
>            Reporter: Chaoyu Tang
>            Assignee: Chaoyu Tang
>         Attachments: HIVE-13509.patch
>
>
> It is quite common that there is the discrepancy between partition directory and its
HMS metadata, simply because the directory could be added/deleted externally using hdfs shell
command. Technically it should be fixed by MSCK and alter table .. add/drop command etc, but
sometimes it might not be practical especially in a multi-tenant env. This discrepancy does
not cause any problem to Hive, Hive returns no rows for a partition with an invalid (e.g.
non-existing) path, but it fails the Pig load with HCatLoader, because the HCatBaseInputFormat
getSplits throws an error when getting a split for a non-existing path. The error message
might looks like:
> {code}
> Caused by: org.apache.hadoop.mapred.InvalidInputException: Input path does not exist:
hdfs://xyz.com:8020/user/hive/warehouse/xyz/date=2016-01-01/country=BR
> 	at org.apache.hadoop.mapred.FileInputFormat.singleThreadedListStatus(FileInputFormat.java:287)
> 	at org.apache.hadoop.mapred.FileInputFormat.listStatus(FileInputFormat.java:229)
> 	at org.apache.hadoop.mapred.FileInputFormat.getSplits(FileInputFormat.java:315)
> 	at org.apache.hive.hcatalog.mapreduce.HCatBaseInputFormat.getSplits(HCatBaseInputFormat.java:162)
> 	at org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigInputFormat.getSplits(PigInputFormat.java:274)
> {code}



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

Mime
View raw message