[HIVE-14047] add primary key on WRITE_SET

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 1.3.0, 2.1.0
• Component/s: Transactions
• Assignee: Steve Yeom
• Reporter: Thejas Nair
• Created: 17/Jun/16 17:35
• Updated: 02/Oct/17 19:25

Description

WRITE_SET table created in HIVE-13395 should some columns in the primary key. I expect most databases to organize the data in a b-tree with primary key as the index (or have an option to do so). That should help in reducing the search space for your prominent queries. As long as columns in the where clause match the prefix of the index, it should greatly reduce the search space.
You can add a autoincrement column to keep it unique if necessary. MySQL (innodb) anyway ends up organizing data on an autoincrement column, which is useless for the queries (see post ).

Issue Links

• is related to: HIVE-13395 Lost Update problem in ACID