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From Roland Johann <>
Subject Re: Delta with intelligent upsett
Date Fri, 01 Nov 2019 06:57:05 GMT
If the dataset contains a column like changed_at/created_at you can use this as watermark and
filter out rows that have changed_at/created_at before the watermark. 

Best Regards

Roland Johann
Software Developer/Data Engineer

phenetic GmbH
Lütticher Straße 10, 50674 Köln, Germany

Mobil: +49 172 365 26 46

Handelsregister: Amtsgericht Köln (HRB 92595)
Geschäftsführer: Roland Johann, Uwe Reimann

> Am 01.11.2019 um 07:52 schrieb Gourav Sengupta <>:
> should not a where clause on the partition field help with that? I am obviously missing
something in the question.
> Regards,
> Gourav
> On Thu, Oct 31, 2019 at 9:15 PM ayan guha < <>>
> Hi
> we have a scenario where we have a large table  ie 5-6B records. The table is repository
of data from past N years. It is possible that some updates take place on the data and thus
er are using Delta table. 
> As part of the business process we know updates can happen only within M years of past
records where M is much smaller than N. Eg the table can hold 20 yrs of data but we know updates
can happen only for last year not before that. 
> Is there some way to indicate this additional intelligence to Delta so it can look into
only last years data while running a merge or update? It seems to be an obvious performance
> Any thoughts?
> -- 
> Best Regards,
> Ayan Guha
> -- 
> Best Regards,
> Ayan Guha

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