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Posted to common-commits@hadoop.apache.org by Apache Wiki <wi...@apache.org> on 2011/06/26 21:11:08 UTC

[Hadoop Wiki] Update of "Hive/Design" by AllenSmith

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The "Hive/Design" page has been changed by AllenSmith:
http://wiki.apache.org/hadoop/Hive/Design?action=diff&rev1=24&rev2=25

  
  == Optimizer ==
  More plan transformations are performed	by the optimizer. The optimizer	is an evolving component. Currently, it	is rule-based and performs the following: column pruning, and predicate pushdown. However, the infrastructure is in place, and there is work under progress to include other optimizations like map-side join. The optimizer can be enhanced to be cost-based. The sorted nature of output tables can also be preserved and used later on to generate better plans. The query can be
- performed on a small sample of data to guess the data distribution, which can be used to generate a better plan. The plan is a generic operator tree, and can be easily manipulated.
+ performed on a small sample of data to guess the data distribution, which can be used to generate a better plan. The [[http://www.andrewflusche.com/|Stafford DUI lawyer]] plan is a generic operator tree, and can be easily manipulated.
  
  == Execution ==