Re: How to convert from DataFrame to Dataset[Row]?

[Sun Rui]

For Spark 1.6.x, a DataFrame can't be directly converted to a Dataset[Row], but 
can done indirectly as follows:

import org.apache.spark.sql.catalyst.encoders.RowEncoder
// assume df is a DataFrame
implicit val encoder: ExpressionEncoder[Row]  = RowEncoder(df.schema)
val ds = df.as[Row]

However, it may be more convenient to convert a DataFrame to a Dataset of Tuple 
or case class corresponding to the row schema. 

> On Jul 16, 2016, at 03:21, Daniel Barclay  wrote:
> 
> In Spark 1.6.1, how can I convert a DataFrame to a Dataset[Row]?
> 
> Is there a direct conversion?  (Trying .as[Row] doesn't work,
> even after importing  .implicits._ .)
> 
> Is there some way to map the Rows from the Dataframe into the Dataset[Row]?
> (DataFrame.map would just make another Dataframe, right?)
> 
> 
> Thanks,
> Daniel
> 
> -
> To unsubscribe e-mail: user-unsubscr...@spark.apache.org
> 

Re: How to convert from DataFrame to Dataset[Row]?

[Mich Talebzadeh]

can't you create a temp table from DF say df.registerTempTable("tmp") and
use that instead?



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On 15 July 2016 at 20:21, Daniel Barclay 
wrote:

> In Spark 1.6.1, how can I convert a DataFrame to a Dataset[Row]?
>
> Is there a direct conversion?  (Trying .as[Row] doesn't
> work,
> even after importing  .implicits._ .)
>
> Is there some way to map the Rows from the Dataframe into the Dataset[Row]?
> (DataFrame.map would just make another Dataframe, right?)
>
>
> Thanks,
> Daniel
>
> -
> To unsubscribe e-mail: user-unsubscr...@spark.apache.org
>
>

How to convert from DataFrame to Dataset[Row]?

[Daniel Barclay]

In Spark 1.6.1, how can I convert a DataFrame to a Dataset[Row]?

Is there a direct conversion?  (Trying .as[Row] doesn't work,
even after importing  .implicits._ .)

Is there some way to map the Rows from the Dataframe into the Dataset[Row]?
(DataFrame.map would just make another Dataframe, right?)


Thanks,
Daniel

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