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From Keith Turner <ke...@deenlo.com>
Subject Re: delete + insert case
Date Wed, 16 Mar 2016 21:04:08 GMT
There are no order guarantees for two mutations added prior to flush being
called.   One possible solution it to have two batch writers.  One for
deletes and flush it first.

On Wed, Mar 16, 2016 at 4:33 PM, z11373 <z11373@outlook.com> wrote:

> Hi,
> I have object abstraction class which delete/add operation will eventually
> translate to calling Accumulo writer.putDelete and writer.put
> To achieve higher throughput, the code will only call writer.flush per
> request (my implementation knows when it's end of request), instead of
> flushing per each delete or add operation.
> In this case we have client request calling my service which for example
> would be:
> 1. delete A
> 2. add A
> 3. add B
>
> I'd expect the end result would be both row id A and B exists in the table,
> but apparently it's only B. I already checked from the log, the order the
> code being executed is delete first before add operation. However, I guess
> since I call flush after all putDelete and put calls being made, Accumulo
> somehow make putDelete 'win' (in same flush cycle), is that correct? If
> yes,
> how to workaround this without sacrificing performance.
>
>
> Thanks,
> Z
>
>
>
> --
> View this message in context:
> http://apache-accumulo.1065345.n5.nabble.com/delete-insert-case-tp16375.html
> Sent from the Developers mailing list archive at Nabble.com.
>

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