Multiple choices questions in Distributed database, two phase commit protocol solved MCQ, What is transaction coordinator, what is transaction manager? who initiates the 2PC protocol in distributed database?
Distributed database solved MCQ - Who initiates the execution of 2PC protocol in distributed transactions
1. Who initiates the Two Phase Commit (2PC) protocol during the execution of distributed transaction?
a) Transaction manager
b) Transaction coordinator
c) Database administrator
d) All of the above
Answer: (b) Transaction coordinator
Execution of 2PC is initiated by the transaction coordinator after the last step of the transaction has been reached.
In distributed database environment, transactions may access several sites (servers). The distributed transactions make use of two components namely, transaction manager and transaction coordinator. Every site has both the transaction manager and transaction coordinator. In distributed database environment, the transaction manager is just like the transaction manager in centralized DBMS. It does handle the concurrent execution of transactions executing locally at that site. Whereas the transaction coordinator coordinating the transactions that originate at that particular site. The responsibility of transaction coordinator includes, initiating the transaction that is requested at that site, coordinating the initiated transaction by distributing sub-transactions to other appropriate sites, and ensuring the safe execution of the transaction at all sites.
|
Related links:
- Go to Distributed Database Quiz page
- Go to Database Management Systems Quiz page
- Go to Distributed Database Home page