[HIVE-6867] Bucketized Table feature fails in some cases

• Type: Bug
• Status: Patch Available
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 0.12.0
• Component/s: HiveServer2
• Assignee: Unassigned
• Reporter: Laljo John Pullokkaran
• Created: 08/Apr/14 21:30
• Updated: 04/May/16 08:15

Description

Bucketized Table feature fails in some cases. if src & destination is bucketed on same key, and if actual data in the src is not bucketed (because data got loaded using LOAD DATA LOCAL INPATH ) then the data won't be bucketed while writing to destination.
Example
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CREATE TABLE P1(key STRING, val STRING)
CLUSTERED BY (key) SORTED BY (key) INTO 2 BUCKETS STORED AS TEXTFILE;
LOAD DATA LOCAL INPATH '/Users/jp/apache-hive1/data/files/P1.txt' INTO TABLE P1;
– perform an insert to make sure there are 2 files
INSERT OVERWRITE TABLE P1 select key, val from P1;
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This is not a regression. This has never worked.
This got only discovered due to Hadoop2 changes.
In Hadoop1, in local mode, number of reducers will always be 1, regardless of what is requested by app. Hadoop2 now honors the number of reducer setting in local mode (by spawning threads).
Long term solution seems to be to prevent load data for bucketed table.

Issue Links

• links to: RB