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Sqoop >> mail # user >> Getting bogus rows from sqoop import...?


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Re: Getting bogus rows from sqoop import...?
So... the verdict appears to be the following:

   - Using --direct with --table produces correct results.
   - Using --query instead of --table absolutely requires using
   --hive-drop-import-delims.
   - --hive-drop-import-delims is not compatible with --direct.
   - Sqoop allows you to use --query and --direct together, but produces
   bogus results.

Considering the nature of --hive-drop-import-delims, I would say it's quite
likely that the above observations only hold true if the data in the
imported table actually contains the conflicting delimiting characters.

In any case, don't take my word for it: test on your own dataset if you're
having any problem. Hopefully the above observations can provide a good
starting point though.

Maybe Sqoop should spit out an error or a warning if --query is used
without --hive-drop-import-delims ...?

--
Felix
On Thu, Mar 21, 2013 at 4:46 PM, Felix GV <[EMAIL PROTECTED]> wrote:

> I seem to be getting a proper output with the above parameters BTW.
>
> I'll try to re-integrate the rest of my more complex ETL query in that
> sqoop job...
>
> Thanks :) !
>
> --
> Felix
>
>
> On Thu, Mar 21, 2013 at 12:47 AM, Felix GV <[EMAIL PROTECTED]> wrote:
>
>> Thanks for your response Jarek :)
>>
>> I've started a new import run with --hive-drop-import-delims added and
>> --direct removed (since the two are mutually exclusive), we'll see how
>> it goes.
>>
>> Going to sleep now. I'll report back tomorrow :)
>>
>> --
>> Felix
>>
>>
>> On Thu, Mar 21, 2013 at 12:42 AM, Jarek Jarcec Cecho <[EMAIL PROTECTED]>wrote:
>>
>>> Hi Felix,
>>> we've seen similar behaviour in the past when the data itself contains
>>> Hive special characters like new line characters. Would you mind trying
>>> your import with --hive-drop-import-delims to see if it helps?
>>>
>>> Jarcec
>>>
>>> On Wed, Mar 20, 2013 at 11:27:58PM -0400, Felix GV wrote:
>>> > Hello,
>>> >
>>> > I'm trying to import a full table from MySQL to Hadoop/Hive. It works
>>> with
>>> > certain parameters, but when I try to do an ETL that's somewhat more
>>> > complex, I start getting bogus rows in my resulting table.
>>> >
>>> > This works:
>>> >
>>> > sqoop import \
>>> >         --connect
>>> >
>>> 'jdbc:mysql://backup.general.db/general?tinyInt1isBit=false&zeroDateTimeBehavior=convertToNull'
>>> > \
>>> >         --username xxxxx \
>>> >         --password xxxxx \
>>> >         --hive-import \
>>> >         --hive-overwrite \
>>> >         -m 23 \
>>> >         --direct \
>>> >         --hive-table profile_felix_test17 \
>>> >         --split-by id \
>>> >         --table Profile
>>> >
>>> > But if I use a --query instead of a --table, then I start getting bogus
>>> > records (and by that, I mean rows that have a non-sensically high
>>> primary
>>> > key that doesn't exist in my source database and null for the rest of
>>> the
>>> > cells).
>>> >
>>> > The output I get with the above query is not exactly the way I want it.
>>> > Using --query, I can get the data in the format I want (by transforming
>>> > some stuff inside MySQL), but then I also get the bogus rows, which
>>> pretty
>>> > much makes the Hive table unusable.
>>> >
>>> > I tried various combinations of parameters and it's hard to pin-point
>>> > exactly what causes the problem, so it could be more intricate than my
>>> > above simplistic description. That being said, removing --table and
>>> adding
>>> > the following params definitely breaks it:
>>> >
>>> >         --target-dir /tests/sqoop/general/profile_felix_test \
>>> >         --query "select * from Profile WHERE \$CONDITIONS"
>>> >
>>> > (Ultimately, I want to use a query that's more complex than this, but
>>> even
>>> > a simple query like this breaks...)
>>> >
>>> > Any ideas why this would happen and how to solve it?
>>> >
>>> > Is this the kind of problem that Sqoop2's cleaner architecture intends
>>> to
>>> > solve?
>>> >
>>> > I use CDH 4.2, BTW.
>>> >
>>> > Thanks :) !
>>> >
>>> > --
>>> > Felix
>>>
>>
>>
>