Chapter 18-46
Copyright © 2004 Ramez Elmasri and Shamkant Navathe
Elmasri/Navathe, Fundamentals of Database Systems, Fourth Edition
Database Concurrency Control
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lGranularity of data items and Multiple Granularity Locking
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An example of a serializable execution (continued):
T1                          T2                                   T3
                             unlock(p12)
                             unlock(f1)
                             unlock(db)                                                                                                                    
unlock(r111)
unlock(p11)
unlock(f1)
unlock(db)
                                                                      unlock (r111j)
                                                                      unlock (p11)
                                                                      unlock (f1)
                                                                      unlock(f2)
                                                                      unlock(db)