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https://issues.apache.org/jira/browse/PIG-1891?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13212672#comment-13212672
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Stan Rosenberg commented on PIG-1891:
-------------------------------------

I wanted to chime in.  I agree with Jakob except I'd name this callback 
'postProcess'.  It's a very easy change to sneak in without any impact on 
existing code.

a) Introduce new interface, say 'StoreFuncOnSuccess' with the method 'void 
postProcess(String location, Job job) throws IOException;

b) Modify PigServer.launchPlan to invoke 'postProcess'.

I think this feature is a must have for complex storage UDFs.
                
> Enable StoreFunc to make intelligent decision based on job success or failure
> -----------------------------------------------------------------------------
>
>                 Key: PIG-1891
>                 URL: https://issues.apache.org/jira/browse/PIG-1891
>             Project: Pig
>          Issue Type: New Feature
>            Reporter: Alex Rovner
>            Priority: Minor
>
> We are in the process of using PIG for various data processing and component 
> integration. Here is where we feel pig storage funcs lack:
> They are not aware if the over all job has succeeded. This creates a problem 
> for storage funcs which needs to "upload" results into another system:
> DB, FTP, another file system etc.
> I looked at the DBStorage in the piggybank 
> (http://svn.apache.org/viewvc/pig/trunk/contrib/piggybank/java/src/main/java/org/apache/pig/piggybank/storage/DBStorage.java?view=markup)
>  and what I see is essentially a mechanism which for each task does the 
> following:
> 1. Creates a recordwriter (in this case open connection to db)
> 2. Open transaction.
> 3. Writes records into a batch
> 4. Executes commit or rollback depending if the task was successful.
> While this aproach works great on a task level, it does not work at all on a 
> job level. 
> If certain tasks will succeed but over job will fail, partial records are 
> going to get uploaded into the DB.
> Any ideas on the workaround? 
> Our current workaround is fairly ugly: We created a java wrapper that 
> launches pig jobs and then uploads to DB's once pig's job is successful. 
> While the approach works, it's not really integrated into pig.

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