Re: HiveException: Stateful expressions cannot be used inside of CASE

2014-10-07 Thread Navis류승우 
Stateful function should be called for all input rows but in if/when
clause, it cannot be guaranteed.

Any reason to declare protect_column function to be stateful?

Thanks,
Navis

2014-09-25 3:42 GMT+09:00 Dan Fan d...@appnexus.com:

  Hi Hive Users:

  I have a hive generic hive udf which is called protect_column.
 The udf works fine when I call it along.
 But when I run the following query:


   select case when id = 5 then protect_column(id, 'age', 12L) else id end
 from one_row_table ;


  It says


  Caused by: org.apache.hadoop.hive.ql.metadata.HiveException: Stateful
 expressions cannot be used inside of CASE


  I was reading the source code. And I think it is related to GenericCase
 and GenericWhen according to


 https://svn.apache.org/repos/asf/hive/trunk/ql/src/java/org/apache/hadoop/hive/ql/exec/ExprNodeGenericFuncEvaluator.java?p=1197837

  Could anyone help explain explicitly what exactly is genericCase
 GenericWhen and why we cannot put the udf inside a case when ?

  Thanks for your time helping me out

  Best

  Dan

HiveException: Stateful expressions cannot be used inside of CASE

2014-09-24 Thread Dan Fan 
Hi Hive Users:

I have a hive generic hive udf which is called protect_column.
The udf works fine when I call it along.
But when I run the following query:



 select case when id = 5 then protect_column(id, 'age', 12L) else id end from 
one_row_table ;


It says


Caused by: org.apache.hadoop.hive.ql.metadata.HiveException: Stateful 
expressions cannot be used inside of CASE


I was reading the source code. And I think it is related to GenericCase and 
GenericWhen according to

https://svn.apache.org/repos/asf/hive/trunk/ql/src/java/org/apache/hadoop/hive/ql/exec/ExprNodeGenericFuncEvaluator.java?p=1197837

Could anyone help explain explicitly what exactly is genericCase GenericWhen 
and why we cannot put the udf inside a case when ?

Thanks for your time helping me out

Best

Dan