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https://issues.apache.org/jira/browse/PIG-259?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12829697#action_12829697
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Alan Gates commented on PIG-259:
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A few comments and questions on this:

1) We should make this work against the load/store branch instead of trunk.  
We're hoping to merge load/store into trunk in a week or two, so it makes more 
sense to put it there.  This will also have implications for load/store.  One, 
it will need to communicate to the new validate function that it's ok if the 
file (or whatever is being overwritten) exists.  Two, load implementations will 
need to handle removing the file (or whatever) if necessary.  For example, 
PigStorage will need to handle removing the file so MR doesn't complain.

2) Should we have overwrite be a keyword (as originally proposed and in the 
patch) or should it be string, like hints in join?  I don't have a strong 
opinion one way or another but I think it's worth considering which we want.

3) Is the semantic of overwrite that it saves whether the file is there or not, 
or that it's an error if the file is not there to write?  Write whether there 
or not makes more sense to me, but I wanted to make sure we all agree on it.

4) What happens when a user requests overwrite and the job fails before it 
runs?  In the current implementation the file will be removed up front, so any 
planning errors will still result in the file being removed.  Also, the file 
will be removed up front, even if the job remains in Hadoop's queue for a long 
time waiting to run.  At the very least, I think Pig should delay removing the 
file until it is ready to launch the job so that type checking errors or 
whatever don't result in the file being removed when the job is not run.


> allow store to overwrite existing directroy
> -------------------------------------------
>
>                 Key: PIG-259
>                 URL: https://issues.apache.org/jira/browse/PIG-259
>             Project: Pig
>          Issue Type: Bug
>    Affects Versions: 0.8.0
>            Reporter: Olga Natkovich
>            Assignee: Jeff Zhang
>             Fix For: 0.8.0
>
>         Attachments: Pig_259.patch
>
>
> we have users who are asking for a flag to overwrite existing directory

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