In addition to join optimization, bucketing helps much in sampling as well. It helps you to choose the sample space, (ie n buckets of m).
Sent from remote device, Please excuse typos
From: Stephen Boesch <[EMAIL PROTECTED]>
Date: Sun, 16 Jun 2013 11:20:49
To: <[EMAIL PROTECTED]>
Reply-To: [EMAIL PROTECTED]
Subject: When to use bucketed tables with/instead of partitioned tables
I am accustomed to using partitioned tables to obtain separate directories
for data files in each partition.
When looking at the documentation for bucketed tables it seems they are
typically used in conjunction with distribute by/sort by and an appropriate
partitioning key - and thus provide ability to do map side joins.
An explanation of when to use bucketed tables by themselves (in lieu of
partitioned tables) as well as in conjunction with partitoined tables
would be appreciated.