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From Stack <st...@duboce.net>
Subject Re: What is the best way to return scanner stats to client from co-processor?
Date Mon, 29 Oct 2018 18:05:14 GMT
On Wed, Oct 24, 2018 at 5:29 PM Alex Baranau <alex.baranov.v@gmail.com>

> Hi,
> I'd like to return some scanner statistics from co-processor back to the
> client. E.g. number of rows filtered out. There isn't a way to add
> an arbitrary attributes to Result object, which would be simplest--e.g. I
> could do that in postScannerNext.
> The only way I can think of, is to add special Result object--again
> in postScannerNext--to the result set. The Result object would carry the
> needed info as bytes and could be watched for and interpreted on the client
> side. Is it reasonable at all? Is it at all dangerous to do that in
> postScannerNext or in general? Would it interfere with some client or
> server-side logic?
> Any ideas are welcome!
> Thank you in advance,
> Alex Baranau

Hey Alex:

Does the ScanMetrics feature help at all in your case (See

On the Result, yeah, it is intentionally dumb -- a package of Cells. A
'speical' Result appended by the CP seems like a good way to go though....
Would be interested if you make progress sir.


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