Jarek,

Yes, there are problems with the text splitter.  I am facing a data base with 
EBCDIC characters and character based keys.  I would need a splitter employing 
different code points to make it work.  However, if we are going to restrict 
its use we ought to do it up front.  That is do not start the map/reduce and 
put out a meaningful message.  We should not generate bad SQL and then die 
ignominiously. 

Waldyn 

-----Original Message-----
From: Jarek Jarcec Cecho (JIRA) [mailto:[email protected]] 
Sent: Tuesday, April 02, 2013 1:07 PM
To: [email protected]
Subject: [jira] [Commented] (SQOOP-976) Incorrect SQL when incremental criteria 
is text column


    [ 
https://issues.apache.org/jira/browse/SQOOP-976?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13620081#comment-13620081
 ] 

Jarek Jarcec Cecho commented on SQOOP-976:
------------------------------------------

Hi [~waldyn],
thank you very much for your feedback. I do understand the simplicity of the 
fix. My concern is that I'm not entirely convinced that we should allow this in 
the first place. 

As you've mentioned using scheme like {{CUST1}} ... {{CUST8}} will fail as soon 
as someone will accidentally insert {{CUST11}}. The database itself won't 
prevent anyone from doing so and Sqoop will never see this row as newly 
inserted. Which at the end might lead to a data corruption. Also comparing 
strings is not efficient from the database perspective and it's actually quite 
dangerous due to various encoding that can be applied (and especially when they 
are changed). We've experienced a lot of troubles with {{TextSplitter}} in the 
past, so I'm afraid that by allowing using string based columns for incremental 
updates, we're just opening another Pandora box.

Jarcec
                
> Incorrect SQL when incremental criteria is text column
> ------------------------------------------------------
>
>                 Key: SQOOP-976
>                 URL: https://issues.apache.org/jira/browse/SQOOP-976
>             Project: Sqoop
>          Issue Type: Bug
>          Components: tools
>    Affects Versions: 1.4.3
>         Environment: incremental import on table using text column
>            Reporter: Waldyn Benbenek
>             Fix For: 1.4.4
>
>


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