[HIVE-12309] TableScan should use column stats when available for better data size estimate

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.14.0, 1.0.0, 1.1.0, 1.2.0
• Fix Version/s: 2.0.0
• Component/s: Statistics
• Assignee: Ashutosh Chauhan
• Reporter: Ashutosh Chauhan
• Created: 30/Oct/15 21:19
• Updated: 16/Feb/16 23:52
• Resolved: 10/Nov/15 22:58

Description

Currently, all other operators use column stats to figure out data size, whereas TableScan relies on rawDataSize. This inconsistency can result in an inconsistency where TS may have lower Datasize then subsequent operators.

Issue Links

• is required by: HIVE-12181 Change hive.stats.fetch.column.stats value to true for MiniTezCliDriver
• links to: RB request