[IMPALA-4357] Fix DROP TABLE to pass analysis if the table fails to load

• Type: Bug
• Status: Resolved
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: Kudu_Impala
• Fix Version/s: Impala 2.8.0
• Component/s: Catalog
• Labels: kudu usability
• Target Version: Product Backlog
• Assignee: Thomas Tauber-Marshall
• Reporter: Matthew Jacobs
• Created: 24/Oct/16 20:34
• Updated: 02/Dec/16 22:09
• Resolved: 02/Dec/16 22:08

Description

In general, we want to be able to drop tables even if they fail to load, since otherwise you might end up with a table in a bad state that can't be dropped.

For example, if a Kudu table is created as a managed table in Impala, then dropped directly in Kudu (i.e. HMS still thinks it exists), then the table must be dropped with "DROP TABLE IF EXISTS". Other operations (including setting TBLPROPERTIES) will fail w/ the error that the table cannot be loaded.

If table 'managed_kudu' is in this state, regular operations will fail because the table does not exist, but even attempting to drop the table without this workaround result in this error:

ERROR: AnalysisException: The table does not exist: table_name: "managed_kudu"
CAUSED BY: TableLoadingException: The table does not exist: table_name: "managed_kudu"

Dropping with `IF EXISTS` does work:

[localhost:21000] > drop table if exists managed_kudu;
Query: drop table if exists managed_kudu