This potentially breaks the ACID properties of Hive.

 

My own take is that export/import functionality was added before ACID 
properties and transactional tables were added to Hive and as such did not 
cater for this type of work.

 

There are two options IMO:

 

1.    Update documentation for import/export to highlight the limitations with 
regard to transactional tables

2.    Provide an alternative mechanism on how to migrate transactional tables. 

 

HTH,

 

Mich Talebzadeh

 

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ISBN 978-0-9563693-0-7. 

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From: sreebalineni . [mailto:sreebalin...@gmail.com] 
Sent: 13 November 2015 05:39
To: user@hive.apache.org
Subject: Re: export/import in hive failing with nested directory exception!

 

Hello Gopal,

Are there any plans for fixing this? Any idea?

 

On Fri, Nov 13, 2015 at 6:31 AM, Gopal Vijayaraghavan <gop...@apache.org 
<mailto:gop...@apache.org> > wrote:

Hi,

>Thanks Gopal. Indeed table t is defined as ORC and transactional.
>
>Any reason why this should not work for transactional tables?

The committed transactions list is actually missing from the exported
metadata.

So the EXPORT as it exists today is a dirty read snapshot, which is not a
good thing when the data is continously being streamed in.

I don't think IMPORT likes that (and why should it?).

Try with a fully compacted table.

Cheers,
Gopal



 

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