You are correct that DbTxnManager does not support the explicit locking
of tables. Instead it obtains locks based on SQL statements that are
being executed.
If you use the DummyTxnManager (the default) and set concurrency to true
and the lock manager to ZooKeeperHiveLockManager then your locks should
go away when the process dies (ZooKeeper handles this for you).
Obviously you have to have a ZooKeeper service set up to use this.
Alan.
Shushant Arora <mailto:shushantaror...@gmail.com>
November 16, 2015 at 10:47
Hi
I have a doubt on hive locking mechanism.
I have 0.13 deployed on my cluster.
When I create explicit lock using
lock table tablename partition(partitionname) exclusive. It acquires
lock as expected.
I have a requirement to release the lock if hive connection with
process who created the lock dies .How to achieve this? In current
situation lock is released only explicitly by calling unlcok table
tbalenme partition(). Requirement is to handle the process which
acquires a lock and gets killed because of any reason before calling
unlock.
While using TxnMgr org.apache.hadoop.hive.ql.lockmgr.DbTxnManager for
handling transaction timeout it did n't allow explicit locking and
threw below exception
FAILED: Execution Error, return code 1 from
org.apache.hadoop.hive.ql.exec.DDLTask. Current transaction manager
does not support explicit lock requests. Transaction manager:
org.apache.hadoop.hive.ql.lockmgr.DbTxnManager
