Home | About | Sematext search-lucene.com search-hadoop.com
 Search Hadoop and all its subprojects:

Switch to Threaded View
Hive >> mail # user >> handling null argument in custom udf

Copy link to this message
RE: handling null argument in custom udf
Could you please look into and share your task log/attemptlog for complete error trace or actual error behind this?

Sent: 04 December 2012 20:28
Subject: Re: handling null argument in custom udf

Thanks. Did you mean I should handle null in my udf or my serde?

I did try to check for null inside the code in my udf, but it fails even before it gets called.

This is from when the udf fails:
Caused by: org.apache.hadoop.hive.ql.metadata.HiveException: Unable to execute method public org.apache.hadoop.io.Text com.company.hive.myfun.evaluate(java.lang.Object,java.lang.Object)
on objectcom.company.hive.myfun@1412332 of class com.company.hive.myfun with arguments {0:java.lang.Object, null} of size 2

It looks like there is a null, or is this error message misleading?
On 04/12/2012 15:43, Edward Capriolo wrote:
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]<mailto:[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
NOTE: This message may contain information that is confidential, proprietary, privileged or otherwise protected by law. The message is intended solely for the named addressee. If received in error, please destroy and notify the sender. Any use of this email is prohibited when received in error. Impetus does not represent, warrant and/or guarantee, that the integrity of this communication has been maintained nor that the communication is free of errors, virus, interception or interference.