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https://issues.apache.org/jira/browse/HIVE-759?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12744348#action_12744348
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Zheng Shao commented on HIVE-759:
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I see. What about no compression/defaultCodec as default?
Yes it does affect only one map-reduce job, but it's possible that one
map-reduce job will output data two times.
For example:
{code}
FROM (SELECT * FROM src CLUSTER BY key) src
INSERT OVERWRITE TABLE tgt1 SELECT a, b, c
INSERT OVERWRITE TABLE tgt2 SELECT d, e, f
{code}
> add hive.intermediate.compression.codec option
> ----------------------------------------------
>
> Key: HIVE-759
> URL: https://issues.apache.org/jira/browse/HIVE-759
> Project: Hadoop Hive
> Issue Type: Improvement
> Components: Query Processor
> Reporter: Zheng Shao
> Assignee: He Yongqiang
> Attachments: hive-759-2009-08-17.patch
>
>
> Hive uses the jobconf compression codec for all map-reduce jobs. This
> includes both mapred.map.output.compression.codec and
> mapred.output.compression.codec.
> In some cases, we want to distinguish between the codec used for intermediate
> map-reduce jobs (that produces intermediate data between jobs) and the final
> map-reduce jobs (that produces data stored in tables).
> For intermediate data, lzo might be a better fit because it's much faster;
> for final data, gzip might be a better fit because it saves disk spaces.
> We should introduce two new options:
> {code}
> hive.intermediate.compression.codec=org.apache.hadoop.io.compress.LzoCodec
> hive.intermediate.compression.type=BLOCK
> {code}
> And use these 2 options to override the mapred.output.compression.* in the
> FileSinkOperator that produces intermediate data.
> Note that it's possible that a single map-reduce job may have 2
> FileSInkOperators: one produces intermediate data, and one produces final
> data. So we need to add a flag to fileSinkDesc for that.
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