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From Shixuan Fan <shixuan....@wisc.edu>
Subject Re: Warning in TupleStorageSubBlock.hpp
Date Sun, 17 Jul 2016 05:15:06 GMT
It seems that bulkInsert() will put the newly inserted tuples right after the last tuple of
the block, so getAttributeValue() and similar methods should work. I didn't check bulkInsert()
in all implementations of TupleStorageSubBlock, so it might be great if you could look into
that.

However, the tuple_id for a specific tuple might change after rebuild(), so I'm not sure if
that would be considered safe or not.

Shixuan
________________________________
From: Navneet Potti <navsan@gmail.com>
Sent: Saturday, July 16, 2016 9:52:51 PM
To: dev@quickstep.incubator.apache.org
Subject: Re: Warning in TupleStorageSubBlock.hpp

Ah, so that just means that index subblocks may potentially have become dirty due to the bulkInsert.
However, it doesn’t mean that functions like getAttributeValue() are potentially broken
too, right? In other words, the TupleStorageSubBlock itself is still guaranteed to be in a
consistent state, only that it may be inconsistent with any index subblocks?

Thanks Shixuan!


> On Jul 16, 2016, at 21:27, Shixuan Fan <shixuan.fan@wisc.edu> wrote:
>
> Hi Navneet,
>
>
> My understanding is that after calling bulkInsertTuples, bulkInsertTuplesWithRemappedAttributes
or insertTupleInBatch, the consistency of the block is broken and the index will not work
until rebuild() is called. Thus any operation based on index or tuple order will not be safe.
>
>
> Hope that others could give a more detailed explanation. :)
>
>
> Shixuan
>
> ________________________________
> From: Navneet Potti <navsan@gmail.com>
> Sent: Saturday, July 16, 2016 8:47:41 PM
> To: dev@quickstep.incubator.apache.org
> Subject: Warning in TupleStorageSubBlock.hpp
>
> Hi Quicksteppers
> I just came across this warning in the documentation for TupleStorageSubBlock::bulkInsertTuples
and bulkInsertTuplesWithRemappedAttributes functions. Can someone explain what it means?
> Cheers,
> Nav
>
> https://github.com/apache/incubator-quickstep/blob/expt_bloom_filter_hash_fn/storage/TupleStorageSubBlock.hpp#L253
<https://github.com/apache/incubator-quickstep/blob/expt_bloom_filter_hash_fn/storage/TupleStorageSubBlock.hpp#L253>
>
>   * @warning The inserted tuples may be placed in an "incorrect" or
>   *          sub-optimal locations in this TupleStorageSubBlock. The only
>   *          methods which are safe to call between bulkInsertTuples() and
>   *          rebuild() are insertTupleInBatch(), bulkInsertTuples(), and
>   *          bulkInsertTuplesWithRemappedAttributes().
>
>


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