Data Base Management System
Concurrency Control
, Concurrency Control
• Concurrency control schemes control the
interaction among the concurrent transaction.
• A Lock is a variable associated with a data item that
describes the status of the item with respected to
possible operations that can be applied to it.
• Lock manager is managed lock granted and
released.
, Concurrency Control conti…
• Locking can be take place at the following levels:
– Database Level
– Table Level
– Page Level(Disk-Page / Disk Block)
– Row( Tuple) Level
– Attribute(or field) Level
Concurrency Control
, Concurrency Control
• Concurrency control schemes control the
interaction among the concurrent transaction.
• A Lock is a variable associated with a data item that
describes the status of the item with respected to
possible operations that can be applied to it.
• Lock manager is managed lock granted and
released.
, Concurrency Control conti…
• Locking can be take place at the following levels:
– Database Level
– Table Level
– Page Level(Disk-Page / Disk Block)
– Row( Tuple) Level
– Attribute(or field) Level
