Is there some place I can read more about it ? I can't find any reference.
I actully want to flatten these structures and not return them from the UDF.
Thanks,
Daniel
On Tue, Nov 25, 2014 at 8:44 PM, Michael Armbrust <mich...@databricks.com>
wrote:
> Maps should just be scala maps, structs are rows inside of rows. If you
> wan to return a struct from a UDF you can do that with a case class.
>
> On Tue, Nov 25, 2014 at 10:25 AM, Daniel Haviv <danielru...@gmail.com>
> wrote:
>
>> Thank you.
>>
>> How can I address more complex columns like maps and structs?
>>
>> Thanks again!
>> Daniel
>>
>> On 25 בנוב׳ 2014, at 19:43, Michael Armbrust <mich...@databricks.com>
>> wrote:
>>
>> Probably the easiest/closest way to do this would be with a UDF,
>> something like:
>>
>> registerFunction("makeString", (s: Seq[String]) => s.mkString(","))
>> sql("SELECT *, makeString(c8) AS newC8 FROM jRequests")
>>
>> Although this does not modify a column, but instead appends a new column.
>>
>> Another more complicated way to do something like this would be by using the
>> applySchema function
>> <http://spark.apache.org/docs/latest/sql-programming-guide.html#programmatically-specifying-the-schema>
>> .
>>
>> I'll note that, as part of the ML pipeline work, we have been considering
>> adding something like:
>>
>> def modifyColumn(columnName, function)
>>
>> Any comments anyone has on this interface would be appreciated!
>>
>> Michael
>>
>> On Tue, Nov 25, 2014 at 7:02 AM, Daniel Haviv <danielru...@gmail.com>
>> wrote:
>>
>>> Hi,
>>> I'm selecting columns from a json file, transform some of them and would
>>> like to store the result as a parquet file but I'm failing.
>>>
>>> This is what I'm doing:
>>>
>>> val jsonFiles=sqlContext.jsonFile("/requests.loading")
>>> jsonFiles.registerTempTable("jRequests")
>>>
>>> val clean_jRequests=sqlContext.sql("select c1, c2, c3 ... c55 from
>>> jRequests")
>>>
>>> and then I run a map:
>>> val
>>> jRequests_flat=clean_jRequests.map(line=>{((line(1),line(2),line(3),line(4),line(5),line(6),line(7),
>>> *line(8).asInstanceOf[Iterable[String]].mkString(",")*,line(9)
>>> ,line(10) ,line(11) ,line(12) ,line(13) ,line(14) ,line(15) ,line(16)
>>> ,line(17) ,line(18) ,line(19) ,line(20) ,line(21) ,line(22) ,line(23)
>>> ,line(24) ,line(25) ,line(26) ,line(27) ,line(28) ,line(29) ,line(30)
>>> ,line(31) ,line(32) ,line(33) ,line(34) ,line(35) ,line(36) ,line(37)
>>> ,line(38) ,line(39) ,line(40) ,line(41) ,line(42) ,line(43) ,line(44)
>>> ,line(45) ,line(46) ,line(47) ,line(48) ,line(49) ,line(50)))})
>>>
>>>
>>>
>>> 1. Is there a smarter way to achieve that (only modify a certain column
>>> without relating to the others, but keeping all of them)?
>>> 2. The last statement fails because the tuple has too much members:
>>> <console>:19: error: object Tuple50 is not a member of package scala
>>>
>>>
>>> Thanks for your help,
>>> Daniel
>>>
>>>
>>
>
