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Two Phase locking protocol prevent deadlock. This protocol maintain the schedule which lock should be granted or not. For more information I think this link help you.
http://www.databaseidea.com/2012/03/two-phase-locking-protocol.html
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What is two phase protocol in a dbms?
In two phase locking there are two phases. The first phase is known as Expanding Phase and locks are issued in this phase. No lock is released. Then after change all changes are committed and the second phase starts that is the Shrinking Phase in which all the changes are noted and the locks are released. No locks are issued in this phase
What is 2pc protocol?
The 2-phase commit (2PC) protocol is a distributed algorithm to ensure the consistent termination of a transaction in a distributed environment. Thus, via 2PC an unanimous decision is reached and enforced among multiple participating servers whether to commit or abort a given transaction, thereby guaranteeing atomicity. The protocol proceeds in two phases, namely the prepare (or voting) and the commit (or decision) phase, which explains the protocol's name.
What are the two parts of a Uniform Resource Locator?
the protocol identifier and the resource name
What is a set of rules and standards that any two entities use for communication?
Protocol
What are the criteria consider to develop a routing protocol?
People use two basic methods to classify routing protocols - by where they are used and by how they calculate routing. You can see how to choose protocols based on where you plan to use them, the way the protocol manages data, and how your router chooses which protocol to use when more than one protocol is installed
What are the advantages of two phase locking?
--guarantees serializability --The protocol utilizes locks that block other transactions from accessing the same data during a transaction's life. by Raja Done M.Tech
What is two phase protocol in a dbms?
In two phase locking there are two phases. The first phase is known as Expanding Phase and locks are issued in this phase. No lock is released. Then after change all changes are committed and the second phase starts that is the Shrinking Phase in which all the changes are noted and the locks are released. No locks are issued in this phase
Advantages of scott connection?
to convert three phase to two phase and vice versa
What benefits does strict two phase locking provide and What disadvantages result?
ADVANTAGE: It produces only cascadeless schedules, recovery is very easy.DISADVANTAGE: The set of schedules obtainable is a subset of those obtainable from plaintwo phase locking, thus concurrency is reduced
Explain the strict two-phase locking protocal in dbms?
The strict two-phase locking (S2PL) class of schedules is the intersection of the 2PL class with the class of schedules possessing the Strictness property. To comply with the S2PL protocol a transaction needs to comply with 2PL, and release its write (exclusive) locks only after it has ended, i.e., being either committed or aborted. On the other hand, read (shared) locks are released regularly during phase 2. Implementing general S2PL requires explicit support of phase-1 end, separate from transaction end, and no such widely utilized product implementation is known. S2PL is a special case of 2PL, i.e., the S2PL class is a proper subclass of 2PL
What is 2pc protocol?
The 2-phase commit (2PC) protocol is a distributed algorithm to ensure the consistent termination of a transaction in a distributed environment. Thus, via 2PC an unanimous decision is reached and enforced among multiple participating servers whether to commit or abort a given transaction, thereby guaranteeing atomicity. The protocol proceeds in two phases, namely the prepare (or voting) and the commit (or decision) phase, which explains the protocol's name.
What are two advantages of using a link-state routing protocol instead of a distance vector routing protocol?
Each router independently determines the route to each network. After the inital LSP flooding, they generally require less bandwidth to communicate changes in a topology.
Two phase instruments?
There is no such thing as a two phase instrument. There is only single phase and three phase. You can only have: single phase/ one pole single phase/ two pole three phase/ three pole
Can you list the Advantages of delta system over star system?
If one phase becomes damaged or open, the remaining two phases can still deliver three-phase power but at a reduced capacity. It is refered to as an open delta.
What are the advantages of three phase to two phase electric power distribution systems?
Polyphase systems are used because they allow the efficient transmission of electric power, in terms of power transmitted per kilogram of wire. Polyphase systems with more than three phases are very uncommon.
Difference between 2-phase locking and 2-phase commit?
2PC and 2PL are protocols used in conjunction with distributed databases. Both together are The two phase lock protocol (2PL) deals uniquely with the fact how are locks are acquired during a transaction whereas the two phase commit (2PC) protocol deals with the fact how do multiple hosts decide wether one specific transaction is written (commited) or not (abort). 2PL sais that first there is a phase where locks are (during a transaction) acquired (growth phase) and then there is a phase where the locks are beeing removed (shrinking phase). Once the shrinking phase started no more locks can be acquired during this transaction. The shrinking phase usually takes place after an abort or a commit phase in a typical database system. The essence of 2PC is that after a transaction is complete and should be commited a vote starts. Each node which is part of the transaction is asked to "prepare to commit". The node will then check wether a local commit is possible and if yes it votes with "ready to commit" (RTC) [Important: changes are not beeing written to the database at that point]. Once a node signaled RTC the system must be kept in a state where the transaction is allways commitable. If all nodes signal RTC the transaction the transaction master signals them a commit. If one of the nodes does not signal RTC the transaction master will signal abort to all local transactions.
List two examples of a routed protocol besides Internet Protocol.?
IPX/SPXAppletalk
