MySQL Bugs: #73599: Prune does not work if table does not exist

Bug #73599	Prune does not work if table does not exist
Submitted:	15 Aug 2014 10:50	Modified:	16 Sep 2014 23:47
Reporter:	Ingo Strüwing	Email Updates:
Status:	Closed	Impact on me:	None
Category:	MySQL Fabric	Severity:	S2 (Serious)
Version:	1.5.1	OS:	Any
Assigned to:		CPU Architecture:	Any

Description:
Fabric behaves inconsistent in respect to sharding of non-existent tables. Most sharding commands work even if the sharded table does not exist. That way, it is possible to set up sharding for a table before it is created and filled with data.

The prune command does not work if the table does not exist.

That alone won't be of high severity. There is no point in pruning a non-existent table. This is not a preparatory step in a sharding setup.

But unfortunately, a split operation causes a prune operation internally. That prune operation fails on a non-existing table. The problem of high severity is that the split operation returns an error although the split has successfully be done and is manifested in the backing store.

How to repeat:
Create some HA groups.
Set up a shard for a non-existent table.
Split the shard.

Suggested fix:
Ignore a non-existent table during a prune operation. Just verify that there exists a shard mapping for the table.

Fixed as of the upcoming MySQL Utilities / Fabric 1.5.2 release, and here's the changelog entry:

Fabric behaved inconsistently with respect to sharding and non-existent
tables.

Thank you for the bug report.