Hi James. Basically if we have a table called table A which is mapped to a directory in hive /data/a . And n is the number of the files under /data/a with each row size s.
hive -e "select * from a limit 10" To show the result very fast hive.limit.optimize.limit.file < n in this case will be 10 and the The hive.limit.row.max.size = s which may vary according the actual data. Hope this helps. The hive.limit.row.max.size control the size of each Hortonworks, Inc. Technical Support Engineer Abdelrahman Shettia ashet...@hortonworks.com Office phone: (708) 689-9609 How am I doing? Please feel free to provide feedback to my manager Rick Morris at r...@hortonworks.com On Jan 24, 2013, at 3:12 PM, "Wu, James C." <james.c...@disney.com> wrote: > Hi, > > Do anyone know the meaning of these hive settings? The description of them > are not clear to me. If someone can give me an example of how they shall be > used, it would be great! > > <property> > <name>hive.limit.row.max.size</name> > <value>100000</value> > <description>When trying a smaller subset of data for simple LIMIT, how > much size we need to guarantee > each row to have at least.</description> > </property> > > <property> > <name>hive.limit.optimize.limit.file</name> > <value>10</value> > <description>When trying a smaller subset of data for simple LIMIT, maximum > number of files we can > sample.</description> > </property> > > Regards, > > James > >
