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Posted to common-commits@hadoop.apache.org by Apache Wiki <wi...@apache.org> on 2010/10/05 18:15:10 UTC
[Hadoop Wiki] Update of "Hive/StatsDev" by Ning Zhang
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The "Hive/StatsDev" page has been changed by Ning Zhang.
http://wiki.apache.org/hadoop/Hive/StatsDev?action=diff&rev1=60&rev2=61
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}}}
then statistics are gathered for the 4 partitions.
- If the user issues the command:
+ For a non-partitioned table, you can issue the command:
{{{
ANALYZE TABLE Table1 COMPUTE STATISTICS;
}}}
- then statistics are gathered for the 4 partitions as well as the table itself.
+ to gather statistics of the table. If Table1 is a partitioned table, you have to specify partition specifications like above. Otherwise a semantic analyzer exception will be thrown.
The user can view the stored statistics by issuing the [[http://wiki.apache.org/hadoop/Hive/LanguageManual/DDL?highlight=(describe)#Describe_Partition|DESCRIBE]] command. Statistics are stored in the Parameters array. Suppose the user issues the analyze command for the whole table Table1, then issues the command:
{{{