On Mon, Jan 24, 2011 at 4:14 PM, yongqiang he <heyongqiang...@gmail.com> wrote: > How did you upload the data to the new table? > You can get the data compressed by doing a insert overwrite to the > destination table with setting "hive.exec.compress.output" to true. > > Thanks > Yongqiang > On Mon, Jan 24, 2011 at 12:30 PM, Edward Capriolo <edlinuxg...@gmail.com> > wrote: >> I am trying to explore some use case that I believe are perfect for >> the columnarSerDe, tables with 100+ columns where only one or two are >> selected in a particular query. >> >> CREATE TABLE (....) >> ROW FORMAT SERDE "org.apache.hadoop.hive.serde2.columnar.ColumnarSerDe" >> STORED AS RCFile ; >> >> My issue is my data from our source table, with gzip sequence files, >> is much smaller then the ColumnarSerDe table and as a result any >> performance gains are lost. >> >> Any ideas? >> >> Thank you, >> Edward >> >
Thank you! That was a RTFM question. set hive.exec.dynamic.partition.mode=nonstrict; set hive.exec.compress.output=true; set mapred.output.compression.codec=org.apache.hadoop.io.compress.GzipCodec; I was unclear about 'STORED AS RCFile' since normally you would need to use ' STORED AS SEQUENCEFILE' However http://hive.apache.org/docs/r0.6.0/api/org/apache/hadoop/hive/ql/io/RCFile.html explains this well. RCFILE is a special type of sequence file. I did get it working. Looks good compression for my table was smaller then using GZIP BLOCK Sequence file. Query time was slightly better in limited testing. Cool stuff. Edward
