[HIVE-2750] Hive multi group by single reducer optimization causes invalid column reference error

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.9.0
• Assignee: Kevin Wilfong
• Reporter: Kevin Wilfong
• Created: 26/Jan/12 02:09
• Updated: 18/Oct/16 22:42
• Resolved: 30/Jan/12 09:53

Description

After the optimization, if two query blocks have the same distinct clause and the same group by keys, but the first query block does not reference all the rows the second query block does, an invalid column reference error is raised for the columns unreferenced in the first query block.

E.g.
FROM src
INSERT OVERWRITE TABLE dest_g2 SELECT substr(src.key,1,1), count(DISTINCT src.key) WHERE substr(src.key,1,1) >= 5 GROUP BY substr(src.key,1,1)
INSERT OVERWRITE TABLE dest_g3 SELECT substr(src.key,1,1), count(DISTINCT src.key), count(src.value) WHERE substr(src.key,1,1) < 5 GROUP BY substr(src.key,1,1);

This results in an invalid column reference error on src.value

Issue Links

• Blocked: HIVE-12412 Multi insert queries fail to run properly in hive 1.1.x or later.