Andrew Or created SPARK-15867:
---------------------------------
Summary: TABLESAMPLE BUCKET semantics don't match Hive's
Key: SPARK-15867
URL: https://issues.apache.org/jira/browse/SPARK-15867
Project: Spark
Issue Type: Bug
Components: SQL
Affects Versions: 2.0.0
Reporter: Andrew Or
{code}
SELECT * FROM boxes TABLESAMPLE (BUCKET 3 OUT OF 16)
{code}
In Hive, this would select the 3rd bucket out of every 16 buckets there are in
the table. E.g. if the table was clustered by 32 buckets then this would sample
the 3rd and the 19th bucket. (See
https://cwiki.apache.org/confluence/display/Hive/LanguageManual+Sampling)
In Spark, however, we simply sample 3/16 of the number of input rows.
Either we don't support it in Spark or do it in a way that's consistent with
Hive.
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
