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The "Hive/Locking" page has been changed by NamitJain.
http://wiki.apache.org/hadoop/Hive/Locking?action=diff&rev1=12&rev2=13

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  In order to avoid deadlocks, a very simple scheme is proposed here. All       
the objects to be locked
  are sorted lexicographically, and the required mode lock is acquired. Note 
that       in some cases, the
  list of objects may not be known - for eg. in case of dynamic partitions, the 
list of partitions
- being modified is not known at compile time - so, the list is generated 
conservatively.
+ being modified is not known at compile time - so, the list is generated 
conservatively. Since the 
+ number of partitions may not be known, an exclusive lock is taken on the 
table, or the prefix that 
+ is known. 
  
  Two new configurable parameters will be added to decide the number of retries 
for the lock and the 
  wait time between each retry. If the number of retries are really high, it 
can lead to a live lock.

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