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From Russell Spitzer <russell.spit...@gmail.com>
Subject Re: Insert non-null values from dataframe
Date Fri, 26 Aug 2016 15:38:09 GMT
Cassandra does not differentiate between null and empty, so when reading
from C* all empty values are reported as null. To avoid inserting nulls
(avoiding tombstones) see

https://github.com/datastax/spark-cassandra-connector/blob/master/doc/5_saving.md#globally-treating-all-nulls-as-unset

This will not prevent those columns from being read as null though, it will
only skip writing tombstones.

On Thu, Aug 25, 2016, 1:23 PM Selvam Raman <selmna@gmail.com> wrote:

> Hi ,
>
> Dataframe:
> colA colB colC colD colE
> 1 2 3 4 5
> 1 2 3 null null
> 1 null null  null 5
> null null  3 4 5
>
> I want to insert dataframe to nosql database, where null occupies
> values(Cassandra). so i have to insert the column which has non-null values
> in the row.
>
> Expected:
>
> Record 1: (1,2,3,4,5)
> Record 2:(1,2,3)
> Record 3:(1,5)
> Record 4:(3,4,5)
>
> --
> Selvam Raman
> "லஞ்சம் தவிர்த்து நெஞ்சம் நிமிர்த்து"
>

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