In MapReduce, filenames that begin with an underscore are "hidden" files and are not enumerated by FileInputFormat (Hive, I believe, processes tables with TextInputFormat and SequenceFileInputFormat, both descendants of this class).
Using "_foo" as a hidden/ignored filename is conventional in the Hadoop world. This is different than the UNIX convention of using ".foo", but that's software engineering for you. ;) This is unlikely to change soon; MapReduce emits files with names like "_SUCCESS" into directories to indicate successful job completion. Directories such as "_tmp" and "_logs" also appear in datasets, and are therefore ignored as input by MapReduce-based tools, but those metadata names are established in other projects. If you run 'hadoop fs -mv /path/to/_top.sql /path/to/top.sql', that should make things work for you. - Aaron On Mon, Jan 31, 2011 at 10:21 AM, yongqiang he <heyongqiang...@gmail.com>wrote: > You can first try to set io.skip.checksum.errors to true, which will > ignore bad checksum. > > >>In facebook, we also had a requirement to ignore corrupt/bad data - but > it has not been committed yet. Yongqiang, what is the jira number ? > there seems no jira for this issue. > > thanks > yongqiang > 2011/1/31 Namit Jain <nj...@fb.com>: > > > > > > On 1/31/11 7:46 AM, "Laurent Laborde" <kerdez...@gmail.com> wrote: > > > >>On Fri, Jan 28, 2011 at 8:05 AM, Laurent Laborde <kerdez...@gmail.com> > >>wrote: > >>> On Fri, Jan 28, 2011 at 1:12 AM, Namit Jain <nj...@fb.com> wrote: > >>>> Hi Laurent, > >>>> > >>>> 1. Are you saying that _top.sql did not exist in the home directory. > >>>> Or that, _top.sql existed, but hive was not able to read it after > >>>>loading > >>> > >>> It exist, it's loaded, and i can see it in the hive's warehouse > >>>directory. > >>> it's just impossible to query it. > >>> > >>>> 2. I don¹t think reserved words are documented somewhere. Can you file > >>>>a > >>>> jira for this ? > >>> > >>> Ok; will do that today. > >>> > >>>> 3. The bad row is printed in the task log. > >>>> > >>>> 1. 2011-01-27 11:11:07,046 INFO org.apache.hadoop.fs.FSInputChecker: > >>>>Found > >>>> checksum error: b[1024, > >>>> > > >>>>1536]=7374796c653d22666f6e742d73697a653a20313270743b223e3c623e266e627370 > >>>>3b2 > >>>> > > >>>>66e6273703b266e6273703b202a202838302920416d69656e733a3c2f623e3c2f7370616 > >>>>e3e > >>>> > > >>>>3c2f7370616e3e5c6e20203c2f703e5c6e20203c703e5c6e202020203c7370616e207374 > >>>>796 > >>>> > > >>>>c653d22666f66742d66616d696c793a2068656c7665746963613b223e3c7370616e20737 > >>>>479 > >>>> > > >>>>6c653d22666f6e742d73697a653a20313270743b223e3c623e266e6273703b266e627370 > >>>>3b2 > >>>> > > >>>>66e6273703b266e6273703b266e6273703b266e6273703b266e6273703b266e6273703b2 > >>>>66e > >>>> > > >>>>6273703b206f203132682c2050697175652d6e6971756520646576616e74206c65205265 > >>>>637 > >>>> > > >>>>46f7261742e3c2f623e3c2f7370616e3e3c2f7370616e3e5c6e20203c2f703e5c6e20203 > >>>>c70 > >>>> > > >>>>3e5c6e202020203c7370616e207374796c653d22666f6e742d66616d696c793a2068656c > >>>>766 > >>>> > > >>>>5746963613b223e3c7370616e207374796c653d22666f6e742d73697a653a20313270743 > >>>>b22 > >>>> > > >>>>3e3c623e266e6273703b266e6273703b266e6273703b266e6273703b266e6273703b266e > >>>>627 > >>>> > > >>>>3703b266e6273703b266e6273703b266e6273703b206f2031346833302c204d6169736f6 > >>>>e20 > >>>> > > >>>>6465206c612063756c747572652e3c2f623e3c2f7370616e3e3c2f7370616e3e5c6e2020 > >>>>3c2 > >>>> f703e5c6e20203c703e5c6e202020203c7370616e207374796c653d > >>> > >>> Is this the actual data ? > >>> > >>>> 2. org.apache.hadoop.fs.ChecksumException: Checksum error: > >>>> /blk_2466764552666222475:of:/user/hive/warehouse/article/article.copy > >>>>at > >>>> 23446528 > >>> > >>> 23446528 is the line number ? > >>> > >>> thank you > >> > >>optional question (the previous ones are still open) : > >>is there a way to tell hive to ignore invalid data ? (if the problem > >>is invalid data) > >> > > > > Currently, not. > > In facebook, we also had a requirement to ignore corrupt/bad data - but > it > > has not > > been committed yet. Yongqiang, what is the jira number ? > > > > > > Thanks, > > -namit > > > > > >> > >>-- > >>Laurent "ker2x" Laborde > >>Sysadmin & DBA at http://www.over-blog.com/ > > > > >
