Before any changes to database structure are attempted one should first:
Options: clearly understand the current structure and contents of the database only., test any changes on a test database only., create a complete backup of the operational database only., All of the above should be done.
Options: A)for relatively permanent collections of data
b.for the size of the structure and the data in the structure are constantly changing
c.for both of above situation
d.for none of above situation
7.The elements of an array are stored successively in memory cells because
Options: (A)by this way computer can keep track only the address of the first element and the addresses of other elements can be calculated (B) the architecture of computer memory does not allow arrays to store other than serially (C) A and B both false (D) A and B both true 4