hadoop-hive-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Todd Lipcon (JIRA)" <j...@apache.org>
Subject [jira] Commented: (HIVE-718) Load data inpath into a new partition without overwrite does not move the file
Date Tue, 25 Aug 2009 21:43:59 GMT

    [ https://issues.apache.org/jira/browse/HIVE-718?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12747668#action_12747668
] 

Todd Lipcon commented on HIVE-718:
----------------------------------

Not sure how that actually helps - if we use an algorithm like:

{code}
for each file to be moved:
  while not successful:
    come up with a random name
    try to move src file to the random name
    if it fails due to dst already existing, try again with a new random name
{code}

then we'd lose the atomicity/isolation - readers would see a partial load during the middle
of the operation.

We can't use that algorithm with atomic directory renames, since Hadoop has the wacky behavior
that move("srcdir", "dstdir") will create "dstdir/srcdir" if dstdir already exists

> Load data inpath into a new partition without overwrite does not move the file
> ------------------------------------------------------------------------------
>
>                 Key: HIVE-718
>                 URL: https://issues.apache.org/jira/browse/HIVE-718
>             Project: Hadoop Hive
>          Issue Type: Bug
>    Affects Versions: 0.4.0
>            Reporter: Zheng Shao
>         Attachments: HIVE-718.1.patch, HIVE-718.2.patch, hive-718.txt
>
>
> The bug can be reproduced as following. Note that it only happens for partitioned tables.
The select after the first load returns nothing, while the second returns the data correctly.
> insert.txt in the current local directory contains 3 lines: "a", "b" and "c".
> {code}
> > create table tmp_insert_test (value string) stored as textfile;
> > load data local inpath 'insert.txt' into table tmp_insert_test;
> > select * from tmp_insert_test;
> a
> b
> c
> > create table tmp_insert_test_p ( value string) partitioned by (ds string) stored
as textfile;
> > load data local inpath 'insert.txt' into table tmp_insert_test_p partition (ds =
'2009-08-01');
> > select * from tmp_insert_test_p where ds= '2009-08-01';
> > load data local inpath 'insert.txt' into table tmp_insert_test_p partition (ds =
'2009-08-01');
> > select * from tmp_insert_test_p where ds= '2009-08-01';
> a       2009-08-01
> b       2009-08-01
> d       2009-08-01
> {code}

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.


Mime
View raw message