RE: What is 2-Phase Commit and 3-Phase Commit in datab...
2-Phase commit
This protocol between the transaction manager and all the resources enlisted for a transaction ensures that either all the resource managers commit the transaction or they all abort.
In this protocol, when the application requests for committing the transaction, the transaction manager issues a prepare request to all the resource managers involved. Each of these resources may in turn send a reply indicating whether it is ready for commit or not. Only when all the resource managers are ready for a commit, does the transaction manager issue a commit request to all the resource managers. Otherwise, the transaction manager issues a rollback request and the transaction will be rolled back.
Latest Answer : In computing, an open system (computing) is a computer operating system that provides interoperability, portability or both, particularly Unix systems ...
I have a Web Server, Application Server, Servlet Engine, Database - all located on separate systems behind firewalls. How will you design an application using 3-tier architecture in this case ?
Latest Answer : 2-Phase commitThis protocol between the transaction manager and all the resources enlisted for a transaction ensures that either all the resource managers commit the transaction or they all abort. ...
Will the View get refreshed immediately when you update a database table. If it does not get refreshed immediately, what method you use to refresh it ?
Some websites will have hierarchical display of items. (For eg, on click of a + symbol, all items under this item gets listed.). How do you store such structure in database (Note: You can store as XML object. But how do you store in database tables without using XML) ?
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Moving All the XML Processing into the Database In the preceding example the database server performs only a part of the XML processing while the rest is still performed by the PHP engine Specifically the database server generates an employees XML document based on the records from the hr employees
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