2011-10-05 COLLECTION

Http://www.itpub.net/thread-1499223-1-1.html

First floor

Which PLSQL block displays the following three lines of numbers after execution?

0

one

two

A

DECLARE TYPE numbers_t IS TABLE OF NUMBER; l_numbers numbers_t: = numbers_t (); BEGIN DBMS_OUTPUT.put_line (l_numbers.COUNT); l_numbers.EXTEND (); l_numbers (1): = 100; DBMS_OUTPUT.put_line (l_numbers.COUNT); l_numbers.EXTEND (); DBMS_OUTPUT.put_line (l_numbers.COUNT); END;/0 12

B

DECLARE TYPE numbers_t IS TABLE OF NUMBER; l_numbers numbers_t: = numbers_t (); BEGIN DBMS_OUTPUT.put_line (l_numbers.COUNT); l_numbers.EXTEND (2); l_numbers (1): = 100; DBMS_OUTPUT.put_line (l_numbers.COUNT); l_numbers (2): = 100; DBMS_OUTPUT.put_line (l_numbers.COUNT); END;/0 22

C

DECLARE TYPE numbers_t IS TABLE OF NUMBER; l_numbers numbers_t: = numbers_t (); BEGIN DBMS_OUTPUT.put_line (l_numbers.COUNT); l_numbers.EXTEND (2); l_numbers (1): = 100; l_numbers.DELETE (1); DBMS_OUTPUT.put_line (l_numbers.COUNT); l_numbers (2): = 100; DBMS_OUTPUT.put_line (l_numbers.COUNT); END;/0 11

D

DECLARE TYPE numbers_t IS TABLE OF NUMBER; l_numbers numbers_t: = numbers_t (); BEGIN DBMS_OUTPUT.put_line (l_numbers.COUNT); l_numbers.EXTEND (2); l_numbers (1): = 100; l_numbers.DELETE (1); DBMS_OUTPUT.put_line (l_numbers.COUNT); l_numbers (1): = 200; l_numbers (2): = 100; DBMS_OUTPUT.put_line (l_numbers.COUNT) END;/0 12

Make up the knowledge points.