Oracle PL/SQL Interview Questions

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PL/SQL interview qiuestions Database

1. Which of the following statements is true about implicit cursors?

1. Implicit cursors are used for SQL statements that are not named.

2. Developers should use implicit cursors with great care.

3. Implicit cursors are used in cursor for loops to handle data processing.

4. Implicit cursors are no longer a feature in Oracle.

2. Which of the following is not a feature of a cursor FOR loop?

1. Record type declaration.

2. Opening and parsing of SQL statements.

3. Fetches records from cursor.

4. Requires exit condition to be defined.

3. A developer would like to use referential datatype declaration on a variable. The variable name is EMPLOYEE_LASTNAME, and the corresponding table and column is EMPLOYEE, and LNAME, respectively. How would the developer define this variable using referential datatypes?

1. Use employee.lname%type.

2. Use employee.lname%rowtype.

3. Look up datatype for EMPLOYEE column on LASTNAME table and use that.

4. Declare it to be type LONG.

4. Which three of the following are implicit cursor attributes?

1. %found

2. %too_many_rows

3. %notfound

4. %rowcount

5. %rowtype

5. If left out, which of the following would cause an infinite loop to occur in a simple loop?

1. LOOP

2. END LOOP

3. IF-THEN

4. EXIT

6. Which line in the following statement will produce an error?

1. cursor action_cursor is

2. select name, rate, action

3. into action_record

4. from action_table;

5. There are no errors in this statement.

7. The command used to open a CURSOR FOR loop is

1. open

2. fetch

3. parse

4. None, cursor for loops handle cursor opening implicitly.

8. What happens when rows are found using a FETCH statement

1. It causes the cursor to close

2. It causes the cursor to open

3. It loads the current row values into variables

4. It creates the variables to hold the current row values

9. Read the following code:

CREATE OR REPLACE PROCEDURE find_cpt

(v_movie_id {Argument Mode} NUMBER, v_cost_per_ticket {argument mode} NUMBER)

IS

BEGIN

  IF v_cost_per_ticket  > 8.5 THEN

SELECT  cost_per_ticket

INTO            v_cost_per_ticket

FROM            gross_receipt

WHERE   movie_id = v_movie_id;

  END IF;

END;

10. Which mode should be used for V_COST_PER_TICKET?

1. IN

2. OUT

3. RETURN

4. IN OUT

11. Read the following code:

CREATE OR REPLACE TRIGGER update_show_gross

      {trigger information}

     BEGIN

      {additional code}

     END;

The trigger code should only execute when the column, COST_PER_TICKET, is greater than $3. Which trigger information will you add?

1. WHEN (new.cost_per_ticket > 3.75)

2. WHEN (:new.cost_per_ticket > 3.75

3. WHERE (new.cost_per_ticket > 3.75)

4. WHERE (:new.cost_per_ticket > 3.75)

12. What is the maximum number of handlers processed before the PL/SQL block is exited when an exception occurs?

1. Only one

2. All that apply

3. All referenced

4. None

13. For which trigger timing can you reference the NEW and OLD qualifiers?

1. Statement and Row

2. Statement only

3. Row only

4. Oracle Forms trigger

14. Read the following code:

CREATE OR REPLACE FUNCTION get_budget(v_studio_id IN NUMBER)

RETURN number IS

v_yearly_budget NUMBER;

BEGIN

SELECT yearly_budget

INTO v_yearly_budget

FROM studio

WHERE id = v_studio_id;

RETURN v_yearly_budget;

END;

15. Which set of statements will successfully invoke this function within SQL*Plus?

1. VARIABLE g_yearly_budget NUMBER

EXECUTE g_yearly_budget := GET_BUDGET(11);

2. VARIABLE g_yearly_budget NUMBER

EXECUTE :g_yearly_budget := GET_BUDGET(11);

3. VARIABLE :g_yearly_budget NUMBER

EXECUTE :g_yearly_budget := GET_BUDGET(11);

4. VARIABLE g_yearly_budget NUMBER

:g_yearly_budget := GET_BUDGET(11);

CREATE OR REPLACE PROCEDURE update_theater

(v_name IN VARCHAR v_theater_id IN NUMBER) IS

BEGIN

       UPDATE  theater

       SET             name = v_name

       WHERE   id = v_theater_id;

END update_theater;

16. When invoking this procedure, you encounter the error:

ORA-000: Unique constraint(SCOTT.THEATER_NAME_UK) violated.

How should you modify the function to handle this error?

1. An user defined exception must be declared and associated with the error code and handled in the EXCEPTION section.

2. Handle the error in EXCEPTION section by referencing the error code directly.

3. Handle the error in the EXCEPTION section by referencing the UNIQUE_ERROR predefined exception.

4. Check for success by checking the value of SQL%FOUND immediately after the UPDATE statement.

17. Read the following code:

CREATE OR REPLACE PROCEDURE calculate_budget IS

v_budget        studio.yearly_budget%TYPE;

BEGIN

       v_budget := get_budget(11);

       IF v_budget < 30000

                                     THEN

               set_budget(11,30000000);

       END IF;

END;

18. You are about to add an argument to CALCULATE_BUDGET. What effect will this have?

1. The GET_BUDGET function will be marked invalid and must be recompiled before the next execution.

2. The SET_BUDGET function will be marked invalid and must be recompiled before the next execution.

3. Only the CALCULATE_BUDGET procedure needs to be recompiled.

4. All three procedures are marked invalid and must be recompiled.

19. Which procedure can be used to create a customized error message?

1. RAISE_ERROR

2. SQLERRM

3. RAISE_APPLICATION_ERROR

4. RAISE_SERVER_ERROR

20. The CHECK_THEATER trigger of the THEATER table has been disabled. Which command can you issue to enable this trigger?

1. ALTER TRIGGER check_theater ENABLE;

2. ENABLE TRIGGER check_theater;

3. ALTER TABLE check_theater ENABLE check_theater;

4. ENABLE check_theater;

21. Examine this database trigger

CREATE OR REPLACE TRIGGER prevent_gross_modification

{additional trigger information}

BEGIN

       IF TO_CHAR(sysdate, DY) = MON

                 THEN

                 RAISE_APPLICATION_ERROR(-20000,Gross receipts cannot be deleted on Monday);

       END IF;

END;

22. This trigger must fire before each DELETE of the GROSS_RECEIPT table. It should fire only once for the entire DELETE statement. What additional information must you add?

1. BEFORE DELETE ON gross_receipt

2. AFTER DELETE ON gross_receipt

3. BEFORE (gross_receipt DELETE)

4. FOR EACH ROW DELETED FROM gross_receipt

23. Examine this function:

CREATE OR REPLACE FUNCTION set_budget

(v_studio_id IN NUMBER, v_new_budget IN NUMBER) IS

BEGIN

       UPDATE  studio

       SET             yearly_budget = v_new_budget

WHERE   id = v_studio_id;

IF SQL%FOUND THEN

RETURN TRUEl;

ELSE

RETURN FALSE;

END IF;

COMMIT;

END;

24. Which code must be added to successfully compile this function?

1. Add RETURN right before the IS keyword.

2. Add RETURN number right before the IS keyword.

3. Add RETURN boolean right after the IS keyword.

4. Add RETURN boolean right before the IS keyword.

25. Under which circumstance must you recompile the package body after recompiling the package specification?

1. Altering the argument list of one of the package constructs

2. Any change made to one of the package constructs

3. Any SQL statement change made to one of the package constructs

4. Removing a local variable from the DECLARE section of one of the package constructs

26. Procedure and Functions are explicitly executed. This is different from a database trigger. When is a database trigger executed?

1. When the transaction is committed

2. During the data manipulation statement

3. When an Oracle supplied package references the trigger

4. During a data manipulation statement and when the transaction is committed

27. Which Oracle supplied package can you use to output values and messages from database triggers, stored procedures and functions within SQL*Plus?

1. DBMS_DISPLAY

2. DBMS_OUTPUT

3. DBMS_LIST

4. DBMS_DESCRIBE

28. What occurs if a procedure or function terminates with failure without being handled?

1. Any DML statements issued by the construct are still pending and can be committed or rolled back.

2. Any DML statements issued by the construct are committed

3. Unless a GOTO statement is used to continue processing within the BEGIN section, the construct terminates.

4. The construct rolls back any DML statements issued and returns the unhandled exception to the calling environment.

29. Examine this code

BEGIN

       theater_pck.v_total_seats_sold_overall := theater_pck.get_total_for_year;

END;

30. For this code to be successful, what must be true?

1. Both the V_TOTAL_SEATS_SOLD_OVERALL variable and the GET_TOTAL_FOR_YEAR function must exist only in the body of the THEATER_PCK package.

2. Only the GET_TOTAL_FOR_YEAR variable must exist in the specification of the THEATER_PCK package.

3. Only the V_TOTAL_SEATS_SOLD_OVERALL variable must exist in the specification of the THEATER_PCK package.

4. Both the V_TOTAL_SEATS_SOLD_OVERALL variable and the GET_TOTAL_FOR_YEAR function must exist in the specification of the THEATER_PCK package.

31. A stored function must return a value based on conditions that are determined at runtime. Therefore, the SELECT statement cannot be hard-coded and must be created dynamically when the function is executed. Which Oracle supplied package will enable this feature?

1. DBMS_DDL

2. DBMS_DML

3. DBMS_SYN

4. DBMS_SQL

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