question Re: Is there any relation of no of buckets with number of reducers? are both should be equal in hive? in Archives of Support Questions (Read Only)

Is there any relation of no of buckets with number of reducers? are both should be equal in hive?

mhdeshmukh22 — Tue, 22 Mar 2016 13:08:20 GMT

Re: Is there any relation of no of buckets with number of reducers? are both should be equal in hive?

pgowthami — Tue, 22 Mar 2016 18:40:11 GMT

As per hive documentation what you have specified at the time of creation of bucket table with no.of buckets is become the number of reducers.If you have huge data single file contains different data.

https://cwiki.apache.org/confluence/display/Hive/LanguageManual+DDL+BucketedTables

Re: Is there any relation of no of buckets with number of reducers? are both should be equal in hive?

mhdeshmukh22 — Tue, 22 Mar 2016 20:39:00 GMT

@ thanks Kazan, there is bit correction with your ans,The command set hive.enforce.bucketing = true; allows the correct number of reducers and the cluster by column to be automatically selected based on the table. Otherwise, you would need to set the number of reducers to be the same as the number of buckets.

Re: Is there any relation of no of buckets with number of reducers? are both should be equal in hive?

mhdeshmukh22 — Tue, 22 Mar 2016 20:39:41 GMT

The command set hive.enforce.bucketing = true; allows the correct number of reducers and the cluster by column to be automatically selected based on the table. Otherwise, you would need to set the number of reducers to be the same as the number of buckets.