PL/SQL Online Quiz

Following quiz provides Multiple Choice Questions (MCQs) related to PL/SQL. You will have to read all the given answers and click over the correct answer. If you are not sure about the answer then you can check the answer using Show Answer button. You can use Next Quiz button to check new set of questions in the quiz.

Q 1 - Which of the following is not true about the declaration section of a PL/SQL block?

A - This section starts with the DECLARE keyword.

B - It is a mandatory section.

C - It defines all variables, cursors, subprograms, and other elements to be used in the program.

D - None of the above.

Answer : B

Q 2 - Consider the following code −

DECLARE
   -- Global variables 
   num number := 95; 
BEGIN 
   dbms_output.put_line('num: ' || num1);
   DECLARE 
      -- Local variables
      num number := 195; 
     BEGIN 
      dbms_output.put_line('num: ' || num1);
     END; 
END;

What will happen when the code is executed?

A - It wont execute, it has syntax error

Answer : B

Q 3 - Which of the following is true about the following PL/SQL CASE statement syntax?

CASE selector
    WHEN 'value1' THEN S1;
    WHEN 'value2' THEN S2;
    WHEN 'value3' THEN S3;
    ...
    ELSE Sn;  -- default case
END CASE;

A - It is wrongly written.

B - It is perfectly written.

C - It is you can specify the literal NULL for all the S expressions and the default S_n.

D - All the expressions like the selector, the value and the returns values, need not be of the same data type.

Answer : B

Q 4 - Which of the following is not true about the PL/SQL data structure VARRAY?

A - In oracle environment, the starting index for VARRAYs is always 1.

B - You can initialize the VARRAY elements using the constructor method of the VARRAY type, which has the same name as the VARRAY.

C - VARRAYs are one-dimensional arrays.

D - None of the above.

Answer : D

Q 5 - Which of the following is not true about PL/SQL cursors?

A - A cursor is a view on a table.

B - A cursor holds the rows (one or more) returned by a SQL statement.

C - The set of rows the cursor holds is referred to as the active set.

D - None of the above.

Answer : A

Explanation

A cursor is a memory area, known as context area, for processing an SQL statement, which contains all information needed for processing the statement.

Q 6 - Which of the following code correctly create a record named book with two field title and author?

A - TYPE book IS RECORD

(title  varchar(50),
    author  varchar(50),
    );

B - RECORD book

(title  varchar(50),
    author  varchar(50),
    );

C - CREATE RECORD book

(title  varchar(50),
    author  varchar(50),
    );

D - CREATE TYPE book

(title  varchar(50),
    author  varchar(50),
    );

Answer : A

Q 7 - Observe the syntax given below −

CREATE [OR REPLACE ] TRIGGER trigger_name 
{BEFORE | AFTER | INSTEAD OF } 
{INSERT [OR] | UPDATE [OR] | DELETE} 
[OF col_name] 
ON table_name 
[REFERENCING OLD AS o NEW AS n] 
[FOR EACH ROW] 
WHEN (condition)  
DECLARE
   Declaration-statements
BEGIN 
   Executable-statements
EXCEPTION
   Exception-handling-statements
END;

Which of the following holds true for the WHEN clause?

A - This provides a condition for rows for which the trigger would fire and this clause is valid only for row level triggers.

B - This provides a condition for rows for which the trigger would fire and this clause is valid only for table level triggers.

C - This provides a condition for rows for which the trigger would fire and this clause is valid only for view based triggers.

D - All of the above.