Technology Questions

main() method is called by the JVM even before the instantiation of the class, hence it is declared as static.

Client code must use setters and getters to access internal data in DataHiding

When ever two or more threads are sharing same data for updating then unpredicted result will be there in the data.

For Example take a thread is depositing amount in Account Object and another thread is withdrawing amount from the same Account Object.

when ever both threads are executed simultaneously then unexpected result is stored in the balance of the  Account Object. 

UNION selects only distinct values whereas UNION ALL selects all values and not just distinct ones

The following commands are available for the Program Control services:

LINK: To pass control to another program at the lower level, expecting to be returned. XCTL: To pass control to another program at the same level, not expecting to be returned.

RETURN:  To return to the next higher-level program or CICS. 

LOAD: To load a program. 

RELEASE: To release a program.

A network in which there are multiple network links between computers to provide multiple paths for data to travel.