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LOCK Query
What is use of lock query in SQL Plus? Give its syntax and implementation?


  
Total Answers and Comments: 1 Last Update: March 17, 2009     Asked by: lpsarathi.edu 
  
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March 17, 2009 05:46:24   #1  
hussasha Member Since: March 2009   Contribution: 1    

RE: LOCK Query

Locking protect table when several users are accessing the same table.
Locking is a concurrency control technique in Oracle. It helps in data integrity
while allowing maximum concurrency access to data. Oracle offers automatic
locking whenever situation requires. This is called implicit locking.


Types of Locking


Shared Lock: This type is placed on a record when the record is being viewed.

Exclusive Lock: This is placed when Insert Update or Delete command is
performed. There can be only one exclusive lock on a record at a time.


 
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