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https://issues.apache.org/jira/browse/SPARK-10868?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Martin Senne updated SPARK-10868:
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    Description: 
With SPARK-7135 and https://github.com/apache/spark/pull/5709 
`monotonicallyIncreasingID()` allows to create an index column with unique ids. 
The indexing always starts at 0 (no offset).

*Feature wish*
Having a parameter `offset`, such that the function can be used as

    {{monotonicallyIncreasingID( offset )}}

and indexing *starts at `offset` instead of 0*.

*Use-case* 
Add rows to a DataFrame that is already written to a DB (via 
_.write.jdbc(...)_).
In detail:
- A DataFrame *A* (containing an ID column) and having indices from 0 to 199 in 
that column is existent in DB.
- New rows need to be added to *A*. This included
-- Creating a DataFrame *A'* with new rows, but without id column
-- Add the index column to *A'* - this time starting at *200*, as there are 
already entries with id's from 0 to 199 (*here, monotonicallyInreasingID( 200 ) 
is required.*)
-- union *A* and *A'*
-- store into DB




  was:
With SPARK-7135 and https://github.com/apache/spark/pull/5709 
`monotonicallyIncreasingID()` allows to create an index column with unique ids. 
The indexing always starts at 0 (no offset).

**Feature wish**: Having a parameter `offset`, such that the function can be 
used as

    {{monotonicallyIncreasingID( offset )}}

and indexing *starts at `offset` instead of 0*.

**Background and justification**: 

Add rows to a DataFrame that is already written to a DB (via .jdbc).
In detail:
- A DataFrame A (containing an ID column) and having indices from 0 to 199 in 
that column is existent in DB.
- New rows need to be added to A. This included
-- Creating a DataFrame **A'** with new rows, but without id column
-- Add the index column to **A'** - this time starting at **200**, as there are 
already entries with id's from 0 to 199 (**here is where 
monotonicallyInreasingID( 200 ) is required.**)
-- union **A** and **A'**
-- store into DB





> monotonicallyIncreasingId() supports offset for indexing
> --------------------------------------------------------
>
>                 Key: SPARK-10868
>                 URL: https://issues.apache.org/jira/browse/SPARK-10868
>             Project: Spark
>          Issue Type: New Feature
>          Components: SQL
>    Affects Versions: 1.5.0
>            Reporter: Martin Senne
>
> With SPARK-7135 and https://github.com/apache/spark/pull/5709 
> `monotonicallyIncreasingID()` allows to create an index column with unique 
> ids. The indexing always starts at 0 (no offset).
> *Feature wish*
> Having a parameter `offset`, such that the function can be used as
>     {{monotonicallyIncreasingID( offset )}}
> and indexing *starts at `offset` instead of 0*.
> *Use-case* 
> Add rows to a DataFrame that is already written to a DB (via 
> _.write.jdbc(...)_).
> In detail:
> - A DataFrame *A* (containing an ID column) and having indices from 0 to 199 
> in that column is existent in DB.
> - New rows need to be added to *A*. This included
> -- Creating a DataFrame *A'* with new rows, but without id column
> -- Add the index column to *A'* - this time starting at *200*, as there are 
> already entries with id's from 0 to 199 (*here, monotonicallyInreasingID( 200 
> ) is required.*)
> -- union *A* and *A'*
> -- store into DB



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