For getting the configuration without configure(), this may not be the best 
thing to do but you can try during your UDF's initialize() method. Note that 
initialize() is called during query compilation, and also by each M/R task 
(followed at some point by configure()).

?During initialize() you can call SessionState.get(), if it is not null then 
this initialize() call is happening during query compilation, and you can then 
use SessionState.get().getConf() to get the configuration. 
GenericUDFBaseNumeric has an example of this.



As for trying to force map/reduce jobs, you can try 
hive.fetch.task.conversion=minimal/none and 
hive.optimize.constant.propagation=false and see how it works.


________________________________
From: Rahul Sharma <kippy....@gmail.com>
Sent: Tuesday, August 25, 2015 2:48 PM
To: user@hive.apache.org
Subject: Re: UDF Configure method not getting called

Or alternatively, is there a way to pass configuration without using the 
configure method?

The configuration to the UDF is essentially a list of parameters that tells the 
UDF, what it should morph into this time and what kind of work it should 
perform. If there is an all encompassing way to do that, then I can modify the 
UDF to run irrespective if its run locally or with MapRed context.

On Tue, Aug 25, 2015 at 2:44 PM, Rahul Sharma 
<kippy....@gmail.com<mailto:kippy....@gmail.com>> wrote:
Oh thanks for the reply, Jason. That was my suspicion too.

The UDF in our case is not a function per say in pure mathematical sense of the 
word 'function'. That is because, it doesn't take in a value and give out 
another value. It has side effects, that form input for another MapReduce job. 
The point of doing it this way is that we wanted to make use of the parallelism 
that would be afforded by running it as a map reduce job via hive, as the 
processing is fairly compute extensive.

Is there a way to force map-reduce jobs? I think hive.fetch.task.conversion to 
minimal might help, is there anything that can be done?

Thanks a ton.

On Tue, Aug 25, 2015 at 2:36 PM, Jason Dere 
<jd...@hortonworks.com<mailto:jd...@hortonworks.com>> wrote:

?There might be a few cases where a UDF is executed locally and not as part of 
a Map/Reduce job?:

 - Hive might choose not to run a M/R task for your query (see 
hive.fetch.task.conversion)

 - If the UDF is deterministic and has deterministic inputs, Hive might decide 
to run the UDF once to get the value and use constant folding to replace calls 
of that UDF with the value from the one UDF call (see 
hive.optimize.constant.propagation?)


Taking a look at the explain plan for you query might confirm this. In those 
cases the UDF would not run within a M/R task and configure() would not be 
called.



________________________________
From: Rahul Sharma <kippy....@gmail.com<mailto:kippy....@gmail.com>>
Sent: Tuesday, August 25, 2015 11:32 AM
To: user@hive.apache.org<mailto:user@hive.apache.org>
Subject: UDF Configure method not getting called

Hi Guys,

We have a UDF which extends GenericUDF and does some configuration within the 
public void configure(MapredContext ctx) method.

MapredContext in configure method gives access to the HiveConfiguration via 
JobConf, which contains custom attributes of the form xy.abc.something. Reading 
these values is required for the semantics of the UDF.

Everything works fine till Hive 0.13, however with Hive 0.14 (or 1.0) the 
configure method of the UDF is never called by the runtime and hence the UDF 
cannot configure itself dynamically.

Is this the intended behavior? If so, what is the new way to read configuration 
of the Map Reduce Job within the UDF?

I would be grateful for any help.


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