Thanks Pablo, That link was really useful. The reason the fieldnames contain NULL, is that I used FLATTEN with TOP, which currently discards the bagname. This is going to be fixed in 0.11 as per https://issues.apache.org/jira/browse/PIG-2365
On Wed, Apr 11, 2012 at 2:55 PM, pablomar <[email protected]>wrote: > this is a very good explanation of flatten: > > > http://ofps.oreilly.com/titles/9781449302641/advanced_pig_latin.html#foreach_flatten > > > > On Wed, Apr 11, 2012 at 9:46 AM, James Newhaven <[email protected] > >wrote: > > > Hi, > > > > Sorry, this is a PIG newbie question... > > > > When I use FLATTEN, I don't understand the structure of the relation that > > is returned. > > > > For example, the following relation A is the result of using flatten: > > > > DESCRIBE A; > > > > A {null::group: chararray,null::tagcount: long} > > > > I'm not really sure why there is "null" prefixing group and tagcount. Can > > anyone help explain what this means? > > > > Thanks, > > James > > >
