A transparent DBMS ?

What is the result of the following SQL statement ?

SELECT A.Employee_Name, B.Spouse_Name
FROM Employee A LEFT OUTER JOIN Spouse B
ON A. Employee_ID = B.Employee_ID

• [A] A list of employee�??s spouses
• [B] A list of all employees that have spouses, with spouse names included in the list
• [C] A list of all employee�??s names, including the name of their spouse if they have one
• [D] Two lists : One list of employees, the other of spouses

Which of the following modifications may not succeed?

• [A] Changing a column data type from char to date
• [B] Changing a column data type from numeric to char
• [C] Both of the above actions should succeed.
• [D] Neither of the above actions will succeed.

The ............ operator preserves unmatched rows of the relations being joined.

• [A] Inner join
• [B] Outer join
• [C] union
• [D] Union join

The concept of data independence is similar to the concept of ?

• [A] Data Type
• [B] Abstract data type
• [C] Consolidation
• [D] Isolation

............. is a special type of stored procedure that is automatically invoked whenever the data in the table is modified

• [A] Procedure
• [B] Trigger
• [C] cursor
• [D] none