[HIVE-1897] Alter command execution "when HDFS is down" results in holding stale data in MetaStore

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.6.0
• Fix Version/s: 0.7.0
• Component/s: Metastore

Environment

Hadoop 0.20.1, Hive0.6.0 and SUSE Linux Enterprise Server 10 SP2 (i586) - Kernel 2.6.16.60-0.21-smp (5).

• Hadoop Flags: Reviewed
• Release Note: HiveAlterHandler ( alterTable ) , In HDFS operation catch block added renaming the table name to old table name.
• Assignee: Chinna Rao Lalam
• Reporter: Chinna Rao Lalam
• Created: 06/Jan/11 14:25
• Updated: 16/Dec/11 23:59
• Resolved: 24/Jan/11 23:28

Description

Lets consider, the "DFS" is down ,

And on executing an alter query say "alter table firsttable rename to secondtable".
the query execution fails with the following exception:

InvalidOperationException(message:Unable to access old location hdfs://localhost:9000/user/hive/warehouse/firsttable for table default.firsttable)

Now after starting the DFS and then executing the same query , the client gets the following exception:

NoSuchObjectException(message:default.firsttable table not found)

Root Cause

In Alter Query execution flow, first "MetaStore" operation is executed successfully and then "DFS" operation is started. In this scenario, "DFS" is down. As a result, execution of the query failed and partial information of the operation is saved.