2011-10-10 COLLECTION EXISTS accepts the performance of NULL parameters

Http://www.itpub.net/thread-1499223-2-1.html

15th floor

I created this help function to display the value of a Boolean variable:

CREATE OR REPLACE PROCEDURE plch_show_boolean (val IN BOOLEAN) ISBEGIN DBMS_OUTPUT.put_line (CASEval WHEN TRUE THEN 'TRUE' WHEN FALSE THEN' FALSE' ELSE 'NULL' END); END plch_show_boolean;/

Which of the following options displays "FALSE" after execution?

(A)

DECLARE my_list DBMS_SQL.number_table; l_index PLS_INTEGER;BEGIN plch_show_boolean (my_list.EXISTS (l_index)); END;/FALSE

(B)

DECLARE my_list DBMS_SQL.number_table; l_index PLS_INTEGER: = 100 × begin plch_show_boolean (my_list.EXISTS (l_index)); END;/FALSE

(C)

DECLARE my_list DBMS_SQL.number_table; l_index PLS_INTEGER: = 100; element_exists BOOLEAN;BEGIN BEGIN l_index: = my_list (l_index); element_exists: = TRUE; EXCEPTION WHEN NO_DATA_FOUND THEN element_exists: = FALSE; END; plch_show_boolean (element_exists); END;/FALSE

(D)

DECLARE my_list DBMS_SQL.number_table;BEGIN plch_show_boolean (my_list.EXISTS (NULL)); END;/FALSE

Answer ABCD

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