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Hive >> mail # user >> handling null argument in custom udf


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Re: handling null argument in custom udf
There is no null argument. You should handle the null case in your code.

If (arga == null)

Or optionally you could use a generic udf but a regular one should handle
what you are doing.

On Tuesday, December 4, 2012, Søren <[EMAIL PROTECTED]> wrote:
> Hi Hive community
>
> I have a custom udf, say myfun, written in Java which I utilize like this
>
> select myfun(col_a, col_b) from mytable where ....etc
>
> col_b is a string type and sometimes it is null.
>
> When that happens, my query crashes with
> ---------------
> java.lang.RuntimeException:
org.apache.hadoop.hive.ql.metadata.HiveException: Hive Runtime Error while
processing row
> {"col_a":"val","col_b":null}
> ...
> Caused by: org.apache.hadoop.hive.ql.metadata.HiveException: Unable to
execute method public org.apache.hadoop.io.Text
> ---------------
>
> public final class myfun extends UDF {
>         public Text evaluate(final Text argA, final Text argB) {
>
> I'm unsure how this should be fixed in a proper way. Is the framework
looking for an overload of evaluate that would comply with the null
argument?
>
> I need to say that the table is declared using my own json serde reading
from S3. I'm not processing nulls in my serde in any special way because
Hive seems to handle null in the right way when not passed to my own UDF.
>
> Are there anyone out there with ideas or experiences on this issue?
>
> thanks in advance
> Søren
>
>