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https://issues.apache.org/jira/browse/PIG-879?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12729859#action_12729859
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Milind Bhandarkar commented on PIG-879:
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I see some long term issues with all the approaches/options.

First, not all loaders require a path. (e.g. DBLoader) Some paths (e.g. hftp:// 
or hsftp://) do not have a notion of relative or absolute. Indeed, the right 
way to fix this is to change the syntax of load and store statements, so that 
the loader itself deals with the path handling, and not pig. Second, take out 
copyToLocal, cp, mv, and all the dfs shell functionality from pig. These are 
side effects and impose a barrier for optimization. In the current form, they 
do not belong in a dataflow language. Grunt could still support it.

> Pig should provide a way for input location string in load statement to be 
> passed as-is to the Loader
> -----------------------------------------------------------------------------------------------------
>
>                 Key: PIG-879
>                 URL: https://issues.apache.org/jira/browse/PIG-879
>             Project: Pig
>          Issue Type: Bug
>    Affects Versions: 0.3.0
>            Reporter: Pradeep Kamath
>
>  Due to multiquery optimization, Pig always converts the filenames to 
> absolute URIs (see 
> http://wiki.apache.org/pig/PigMultiQueryPerformanceSpecification - section 
> about Incompatible Changes - Path Names and Schemes). This is necessary since 
> the script may have "cd .." statements between load or store statements and 
> if the load statements have relative paths, we would need to convert to 
> absolute paths to know where to load/store from. To do this 
> QueryParser.massageFilename() has the code below[1] which basically gives the 
> fully qualified hdfs path
>  
> However the issue with this approach is that if the filename string is 
> something like 
> "hdfs://localhost.localdomain:39125/user/bla/1,hdfs://localhost.localdomain:39125/user/bla/2",
>  the code below[1] actually translates this to 
> hdfs://localhost.localdomain:38264/user/bla/1,hdfs://localhost.localdomain:38264/user/bla/2
>  and throws an exception that it is an incorrect path.
>  
> Some loaders may want to interpret the filenames (the input location string 
> in the load statement) in any way they wish and may want Pig to not make 
> absolute paths out of them.
>  
> There are a few options to address this:
> 1)    A command line switch to indicate to Pig that pathnames in the script 
> are all absolute and hence Pig should not alter them and pass them as-is to 
> Loaders and Storers. 
> 2)    A keyword in the load and store statements to indicate the same intent 
> to pig
> 3)    A property which users can supply on cmdline or in pig.properties to 
> indicate the same intent.
> 4)    A method in LoadFunc - relativeToAbsolutePath(String filename, String 
> curDir) which does the conversion to absolute - this way Loader can chose to 
> implement it as a noop.
> Thoughts?
>  

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